APOCALYPSE AUDIO

E EURO TRANSISTOR INFO

2012-01-18T21:06:00.000-06:00

FSB member kindafuzzy posted this link to the forum today. it has some valuable transistor info on some of the eastern European transistors you can find on eBay. included are the NPN Ge 10XNU71, and the MP14 that I use in many of my circuits. these transistors are still easily found, and don't demand the crazy prices of western euro trannies.

LINK.

DIRTY BOOTS V6

2011-12-08T22:20:00.003-06:00

so i finally got my buddy's dirty boots finished. it's going to be used on guitar and organ, so i added a couple extra controls. a pre-bass and post-treble tone control combo work great together. this is the main recipe for filtering distortion pedals, so it's no surprise. i plan on doing a full overhaul of this design in the future, to see if i can optimize it any further, but until then, this one sounds great. here's the schematic i ended up with.

and some gut shots.

unfortunately i ran out of alpha pots in the values i needed, but the ones i ended up using are of decent quality. here's a couple clips i made of the harder fuzz that this pedal can do. the first is the DB by itself, the second is boosted. disregard the titles. it was 5:30 am when i got this thing finished last night.

BLACK MUFF MODS

2011-12-07T21:46:00.002-06:00

recently, keith from the band MY COLD DEAD HAND, asked me to replace a faulty switch on his Black Russian Big Muff. well, of course i couldn't just leave it at that! i rewired the whole thing, and added lots of new modifications. it turned out extremely heavy and doomy. he loves it! this is what i ended up with-

DIRTY BOOTS TRANSISTOR OPTIONS

2011-11-13T04:59:00.003-06:00

ok, when jamming with my buddy who is a keyboard player a while back, I brought my DB prototype along. I kept telling the guy his organ sound needed some grit, and he kept telling me his Nord synth had distortion built in, no need for a pedal. (wha??) i finally convince him to plug in the DB, and holy shit- perfect Hammond organ overdrive. smooths out the digital top end and everything. sounds fantastic! so now of course he wants one. I slapped one together with some GT313s I picked up a while back, and I realized jus how noisy these things are. they have a great smooth top end- I think due to their very low frequency response, but man do they hiss. I can see why I wput such large Miller Effect caps in the original. so I tried some others- for Q1, I put in the lowest noise devices I have- an American made 2N1307. it was untested, but these have low leakage, and usually have gains somewhere around 100-120. I found that Q2 is much more critical. GT308s to work fine, but didn't have the right overdrive sound- more of a fuzzy distortion. I found an MP16 with a gain of about 50, and that was very nice sounding, but it was the only one in the batch that i had that had that sound. there was a strange "3" stamped on the top of the can in red. probably some sort of sorting mark. to get the classic dark and full DB sound, I think a 313 in that position is still the best. nice smooth sound. higher gained transistors like the 308 and 1307 provided an excellent fuzz sound, but the lower gain models really work well in the second position for a germanium overdrive. now, I didn't tweak any values at all, just swapping trannies in sockets. I had collector resistors of 100R, so by raising those, and adjusting collector biasing you could probably make others work as well.

so just because you don't have the exact transistors, you can still build a Dirty Boots! just experiment, and find a use for those low gain Ge's!!

CUSTOM STRING TENSION CHARTS

2011-10-27T23:28:00.000-05:00

HERE is a post containing customized string tension charts. most strings don't have what are considered "proper" string tension- meaning they don't have even tension on each string. these customized string guages are supposed to remedy this situation, supposedly making quite a difference in your guitar setup. I haven't tried it yet, but I plan on it sometime soon. if anyone has tried this before, let me know!

CONTEST ENTRY - DUST DEVIL

2011-09-23T03:30:00.000-05:00

HERE is a link to my entry in the design contest over at FSB. it's the preliminary version of a new germanium vibra/trem circuit. I used the basic oscillator from the magnavibe(with some tweaks), and went from there. I did a write up and a hand drawn schem, but once I get everything proper, I'll post it here. take it easy!

just a little update.

2011-09-21T18:28:00.001-05:00

haven't posted in a while, so I just thought I'd say a couple things.

first, I noticed that I've got a few new followers on the blog, and just wanted to say thanks for signing up. this blog has basically documented my pedal designing fun, from novice to just a bit more than novice. glad you think it's worth hitting that button.

second, I have a couple new projects in the works. one is called the Vintage Vocalizer, and the other is a vibe/trem called to Dirt Devil. the first is an effect for vocalists that like that old nasty sound of blown mic pres slammed to taped from th days of yesteryear, or full on jourgenson-esque nastiness. if you ever thought your vocals were just too clean, this thing will be the thing for you. it's based off an older design that uses a cascode gain stage, and for some reason, this type of stage just works great with vocals. it really avoids that "I'm singing through a fuzzbox" sound, and breaks up just perfectly when you lay into it. it'll have a 1/4 in input so you can still use it as a guitar pedal, a transformer coupled xlr in, and a parallel xlr out- so you can send some of your clean vocal to the PA or monitors if you want. the output will have to be coupled to a direct box, unless I figure out how to add a balanced out by then. although, I like the idea of unbalanced, because it is a really nice booster for guitar as well. optimally, it will have both, but we'll see.

the Dirt Devil is a vibrato pedal that I came up with after toying with the Magnavibe over at FSB. i made some upgrades, modifications, and added some new controls as well. first, a FET buffer was added on the input to help with the grisly input impedance and brighten things up a bit. then, the main transistor in the preamp was changed to an NPN Ge, because attached to it are two new controls. the first is labelled Grit, and added a bit of gain and drive, giving it a nice vintage pumping feel, and makes it able to change the texture considerably. the second is a symmetry control, which can take this thing into all kinds of different wobble territories. you can get an almost chorus like effect out of it at times. these controls also allow it to be used as a great booster when the depth is turned down. hopefully I'll have this guy ready to show by the end of the month for the circuit design contest over at FSB. of course schematics will be posted when I get them drawn up.

take it easy!

4HMEN -> TOECUTTER - DOOM KONTROL.

2011-08-12T13:56:00.000-05:00

here are some clips of the four horsemen into the toecutter. heavy ain't it? I think I might like to put these both into one box.

5 E-TOOLS YOU MIGHT NOT KNOW ABOUT.

2011-06-27T21:42:00.000-05:00

i recently found this great article about some handy electronics tools that might not have hit everyone's radar. besides these, I would personally like to add the rounded needle nose pliers to the list. they are perfect for bending leads and routing wire without marring the insulation. happy building!

LINK.

PEDAL GUTS PERSONALITY TEST

2011-06-25T13:53:00.002-05:00

THIS is pretty hilarious.

FOUR HORSEMEN GUTS & V1 SCHEMATIC

2011-06-25T06:57:00.011-05:00

here is a 4H i built up for a very patient member of FSB. I think it turned out pretty well! below that is the latest schematic with the output buffer added. click on the image or link to see them fully. such is the way when blogging from your phone!

I really kinda dig this layout, too. it gives the user the option of positioning the pedal vertically, with both jacks on one side(saving space), or horizontally, with top mounted jacks. the knobs on the front side keep them well out of the way of the stomping foot, which also leaves a nice canvas for whatever graphics might be used. sooner or later, I'll have to decide on a form factor and stick with it, but as of right now, every new pedal is a different challenge. I'm kind of looking forward to the day when I don't have to measure everything out for the new box, knobs, and layout I'm using, but it's definitely helping me get my chops up.

btw- I have since separated the battery wire from the input cable. even though it's shielded, and I heard no hum, I wanted to be sure, and it's just good practice.

HERE is a link to the latest schematic on freestompboxes.org.

MONTARBO SINFHOTON - VERO LAYOUT

2011-06-25T06:42:00.001-05:00

after seeing THIS VIDEO, I was once again intrigued by the MONTARBO SINFHOTON. after finally hearing it, i figured I would whip up a vero layout. you can find it in THIS THREAD ON FSB. I'll try and get around to building it soon, but it has been double checked by another forumite who could only find one small correction, which is detailed in the thread. later, I will also post a layout for the earlier two knob model. a nice modification to this circuit would be a pot on the input for gain, as it is fixed in the original.

AES 1973- TUBES VS. TRANSISTORS

2011-06-15T17:33:00.001-05:00

HERE is a cool article from an issue of the Journal of the Audio Engineering Society of New York circa 1973 entitled "Tubes vs. Transistors- Is There an Audible Difference?" it's a neat read, and probably one of the first times solid state designs were thought of as less desirable sounding than tubes.

ASSLOAD OF PAIA DOCS

2011-06-08T19:21:00.005-05:00

HERE is a link to the Paia forum with 4 pages worth of projects and their original documentation. included is the ubiquitous Rocktave Divider among others. unfortunately many designs use the now extremely rare 4136 ICs, so the layouts will have to modified or redrawn. none the less, the schematics are there, along with breakdowns of the circuit as well as construction instructions. check it out. i'm sure there is something there from the Paia workshop that you haven't yet seen..

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FSB forumite roseblood, pointed out to me that you can get the 4136 on eBay pretty easily. he's got a vero layout that uses a 4136 for a dual tube screamer circuit. check it out over at freestompboxes.org!

spring reverb tanks explained.

2011-05-01T02:37:00.001-05:00

interested in spring verbs? well, HERE is a great article on the Amplified Parts company blog on spring reverb tanks. i have yet to read it, but it looks pretty cool.

SOULSONIC FOUR BANGER V1 SCHEMATIC/LAYOUT

2011-04-17T19:24:00.000-05:00

my buddy, martin from soulsonicfx, recently posted his layout for the totally awesome fourbanger. check it out. it's awesome.

http://solgrind.wordpress.com/2011/02/18/original-four-banger-schematic-layout/

a better treble bleed(bright cap) circuit?

2011-04-15T04:02:00.001-05:00

on the guitarnuts forum, someone recently posted a new way to implement a treble bleed circuit using a cap, a resistor, and a dual potentiometer. the idea is, to properly emulate the frequency boost you get from the inductance of the coil in the pickup, even when your volume is rolled back. you can find the schematic, complete with frequency plots for a number of different treble bleed circuits HERE. now, how to incorporate it into a stompbox gain control...

adding a logo to your Eagle files

2011-04-15T03:52:00.000-05:00

HERE is an excellent tutorial on Tasif Khan's page that shows you how to import your own logo for use in eagle. this is a great way to get past the limited amount of fonts that eagle has to offer. although, I have to admit, I do have a small spot in my heart for the vector font. it's just so damn old school!

capacitor switching techniques

2011-04-15T03:46:00.000-05:00

cap switching is a great way to get more sounds out of your circuits. positioning switches at coupling caps(input or output), bypass caps, bright caps on gain controls, or tone controls can unleash options in circuits that you didn't know you had. here is a great article on Rick Viola's site where he goes in-depth into ways of cap switching that you might not have thought about yet.

LINK

pot codes

2011-04-15T03:38:00.000-05:00

the legendary Joe Gagan found this info on a vintage radio site. I thought it was definitely worth reposting. thanks, Joe!

found this info at an old radio parts site.
this info may apply to pots made between 1930s through 60s, possibly into 70s and 80s. use the following at your own risk:

CLAROSTAT TAPERS:
Z = audio taper
S = linear taper
V = c bias taper (right hand taper)
T = ant. & c bias taper
U = left hand ant. & c bias taper
W = left hand taper
L = left hand taper
N = left hand taper (screen grid, regen, phono pickup)
Y = audio shunt & AVC when taper desired

Tapers: Z = Audio Taper, S = Linear Taper

----------------------------------------------

IRC POTS: I have some "B" elements (like "Q")
than can be used in custom pots - inquire
They can also be used to make gang controls
but I have no time or knowledge to make any
complicated controls

IRC TAPERS:
13 = audio
11 = linear
14 = reverse taper
17 = special or tone audio
18 = special or tone audio
19 = special or tone audio

Most of the IRC pots with taps are for
use in volume and tone audio circuits

Example: Q13-137 is a audio taper pot
Example: Q11-137 is a linear taper pot.

---------------------------------------------

Allen Bradley (Ohmite) tapers:
U = linear
J = taper (such as audio)
A = unknown taper

---------------------------------------------

CENTRALAB / CRL tapers:
6 = audio taper
1 = linear
2 = right hand taper
3 = taper both ends
4 = short taper, left end
C1 = linear taper
C2 = audio taper
C3 = reverse audio taper
C4 = audio taper - modified log 20% center,left hand
C5 = reverse audio - modified log 20% center, right hand
C6 = semi linear taper modified log 40%, volume, ant. shunt, c bias
C7 = semi linear taper
C11 to C17 = volume with tone comp.
---------------------------------------------

MALLORY TAPERS:
#1 = audio taper
#2 = logrithmic right hand taper
#3 = left/right taper (ant., Shunt & Bias Circuits)
#4 = linear taper

NAGA FUZZ/DRIVE

2011-04-09T02:47:00.006-05:00

alright, as promised, here is my latest fuzz. I described what I was shooting for a bit in THIS post. basically, I want to simplify my dirt setup, getting rid of the need for a boost, and I wanted it to be extremely versatile, with the simplest amount of controls.
now, the style of music I've been playing lately is influenced by sixties style blues punk a la gories, sonics, oblivions, them, dirtbombs, blue cheer, black keys, etc., so I really wanted to pedal to be able to do a nice, low fi-ish, but very musical, overdrive- similar to a blown up tweed, as well as a high gain sixties style fuzz for the single string square wave kind of sound. most sixties fuzzes really do not have enough sustain, and the ones that do, lack that phased out fuzzrite kind of thing that is so cool about sixties fuzz. so, since we are talkin simple here, I want to get all of that from the volume knob- none of that double stomp switch shit.
what design cleans up the best, and has that crazy impedance thing that actually brightens up when you roll back your volume knob? you guessed it, the venerable fuzz face, perfect for the first stage. many folks will bemoan the FF's input impedance, saying it ain't proper and all, but remember- this is all about simplicity. I don't need it to "play nice" with other pedals before it. it's gonna be first in the chain, and there it will stay. the clean up quality just simply outweighs any negatives that might come up.
so we have the base fuzz face design, but hey, that's kinda boring right? and it won't do the zip gun fuzz that we want with the volume dimed. enter transistor number 3. your basic inverting amplifier, but with a catch. after it is a good amount of negative feedback connected to the output of the FF stage, set up kind of like a fuzzrite with the gain almost all the way up. this gives it that bit of out of phase edge, as well as taming the gain and noise a bit, with the 4n7 cap reducing some highs.
after the fuzz face/rite action is the tone control. I wanted something that was going to be very versatile, just in case someone else isn't into the same exact sounds as me, or if it gets tried out with bass or whatever else might come up. the tc is similar to a muff style control, but the high pass cap is switchable into three ranges. the stock .001 cap gives you a very scooped sound that can do extremely bright, or rolled back gets into doom territory. adding in the 3n3 cap is usually where I keep it. you get a great upper mid crunch, that sounds great with the volume rolled back(think lofi tweed explosion), or does a nice cutting fuzz turned up. with the final option, the .01 cap in parallel with the stock 1n, on one side the heavy lows get filtered out. this gives you a nice full range sound without the mud. great for folks that want to use this as an overdrive. on the other side of the pot, all the highs get rolled off, leaving the low end intact- perfect for a fat bass sound.
you have probably noticed that this circuit uses PNP Ge transistors, so I threw a max1044 voltage converter on the power rail, so guys can use regular center positive DC jacks. all transistors are low leakage 2n1307 Ge's, with around 100-120Hfe. the pcb is not verified yet, although it is fully checked in Eagle. I will be building one up shortly for the other guitarist from the Dead Feathers. I think it'll be perfect for him.
so, there ya have it- the Naga Fuzz. i was going to call it the Nagasaki, but glorifying all that carnage made me feel kinda creepy. so now it's named after the freaky reptoid alien dudes from ancient Indian histo... I mean mythology;). look em up, some wild shit. I hope some of you guys at least take the time to throw it on the breadboard, I'm pretty happy with it. i'll try and get a YouTube video up soon.

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first mod! adjust R14 for more/less separation between the two filters in the tone stack i.e. more/less low/high end roll off at the extremes. for bass, try omitting it all together. my prototype has a 100K pot here. perhaps I'll ad a trimmer in a later revision.

gah! I just noticed the power filtering caps along the bottom of the board are just barely uneven. I'm going to have to fix that, or it's going to bug me forever!

GREEN BOMB SOUND CLIP

2011-03-27T11:37:00.000-05:00

here's a clip of the Green Bomb that FSB forumite pillof made a while back. I stupidly forgot to add it to the blog. thanks pillof!!
GREEN BOMB SOUND CLIP

FEATHER FUZZ #1- and POST #100!!!

2011-03-27T10:06:00.008-05:00

hey, it's post number 100! let's party!! man, this blog has been fun so far, so I'm looking toward 100 more. thanks to everyone who has been following along with me, your comments mean a lot, and I hope to see you around in the future. here's my latest pedal that I'm rather proud of, I think it's fitting for the big 1 0 0.

i've been commissioned by a great band out of Champagne, IL ,called the Dead Feathers, to create a couple of fuzzes for them. they weren't satisfied with their current fuzz tones, and i told them i'd be glad to give them a hand. the first one is for one of the guitarists that plays mainly fingerstyle guitar. he was looking for something with a decent amount of attack, and they are into the garage rock/sixties style stuff, so i thought the Green Bomb would be great. i added the addition of a JFET input buffer, because i feel it evens out the inconsistencies that can come from playing with ones fingers, and it gives the signal a bit of extra oomph that might be needed to keep the attack when playing without a pick. i did the layout on vero, as i don't have a pcb made up for this particular design yet, and made a few modifications when i tuned the circuit by ear. the pedal has some cool, old, low gain, two-tone, T-106, Si transistors i picked up a while ago from a surplus guy on ebay, and pretty much run of the mill metal film resistors, box caps and a couple ceramics in the filter sections. the electrolytics are some nice audio grade ones i just picked up from a dealer in poland. another thing i did with this build, is instead of snapping off the tabs on the pots, i drilled the extra small holes, and mounted them properly- thats not something you see a pedal builder do everyday!;) Dirk Hendrik would be proud! the finish is an awesome plum sparkle with dark green heathkit knobs, topped off with extra large rubber feet and a green led. it really looks killer in person. the pedal is sounding really cool too, and i think he'll be happy with it. stay tuned for the second pedal- it's going to be an all new design.

disregard the scuff on the the tone knob.^^^ it's getting replaced.

sorry the 2 pics above are kind of blown out, i took them indoors in crappy light. although, they do kind of have a cool early seventies grainy b movie style to them that i kind of like!

transistor testing app note

2011-03-24T00:02:00.000-05:00

HERE is a link to a cool .pdf app note on transistor testing. it should come in handy when you aren't sure if you've got a dud or not.

NEW FUZZ CIRCUITS IN THE WORKS

2011-03-23T23:39:00.000-05:00

I just wanted to give you guys a heads up- the next generation of Apocalypse Audio fuzz circuits are being cooked up as we speak. I have been putting one of the latest through it's paces during practice with my latest project, and it's coming through excellently. the idea was to have one pedal that can clean up into a nice overdrive with the rollback of the volume knob, and can be turned up into a nasty, but musical, old school sixties style fuzz with tons of gain on tap. I wanted to be able to use one fuzz, and be able to get multiple tones, with enough gain that no booster was needed. this would allow me to simplify my pedal setup considerably, which has become a sort of mantra of late. what I ended up with was a sort of 3 transistor fuzz face/fuzzrite/big muff frankenstein hybrid that has enough flexibility to be usable with any rig and go from wooly, to cutting, to clear, whenever you want. it also is able to clean up in a sort of jekyll and hyde fashion- for overdriven chord work, or single string stun gun action with the flick of the wrist. stay tuned for schematics, project files, and demo videos soon.

NAT SEMI APP NOTE 31 - AUDIO OP AMP CIRCUITS

2011-03-23T23:11:00.001-05:00

HERE is a link to national semiconductor app note number 31. it's a virtual bevy of op amp circuits. from the most basic to the obscure, they all have an example in this application note.

THE GERMANIUM REVIVAL

2011-03-23T21:32:00.000-05:00

fsb moderator, and good buddy, GregG posted this link about the revival of germanium with hybrid Si devices. it's a really fascinating read. Ge kicks ass! FTW!

LINK

10 DOLLAR ALDI SUCTION VISE

2011-02-24T22:27:00.001-06:00

ok, besides their awesome sweet potato fries, cheap cereal, euro chocolate, and biscuit tins, Aldi has once again made me glad to be a customer. because, today I picked up this awesome vice for under 10 bucks!
(click on the images to expand them)

I was planning on eventually getting a panavise model to match my panavise jr, but now there's no need. Aldi flips their stock regularly, and changes these specialty items out all the time, so there's no guarantee that they'll have them. but, if you see them there, pick one up, because they'll probably never carry them again!

PROTOTYPE FUZZ

2011-02-20T21:49:00.003-06:00

i thought i'd take a little time to show you guys how i build my prototypes. this is a new fuzz i've been working on that is a kind of cross between the fuzz face and the fuzzrite. usually when i build up a proto for the first time, i'll just grab a piece of vero and start populating, and that's what i did here. i'll try to cut a piece of vero that looks like it's got plenty of room, but this time i think i just made it.;) the boxes that i usually use are these computer switching boxes that i bought on ebay for super cheap. i think i got 8 of them for 15 bucks or so. sometimes i'll stip the paint off with acetone, leaving the box sit in the chemicals for days. what ends up happening is a really cool weathered and corroded finish that lightly rusts and changes with age. i really like the look of it. the pots i've been using are these used mil spec Allen-Bradleys that you can get on line for a buck a piece. i'll spray clean and lube them up to try and bring some life back into them if they need it. knobs will be whatever i've got lying around. many times my pots and knobs don't match, but i don't really care, it's just for me to use. i've got a number of pedals that i've made up for myself like this. usually i'll etch a pcb and put it in a nice box from PE.com if i am happy with the sound. hopefully this helped some of you out there with building your proto effects!

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I put this guy through hs paces the other day with great results! I'll post a full write up soon.

OSVALVE TONE STACK ARTICLE

2011-02-08T05:19:00.004-06:00

here's another little gem I found on the Osvalve site. a great article on tone stacks. enjoy!

http://www.ozvalveamps.org/tonestacks.htm

a comment from a Russian friend.

2011-02-02T05:55:00.002-06:00

I received this very nice comment from a reader of the blog who lives in Russia, so I thought I would share it here.

Good day! I apologize for my English. I'm from Russia. Build your overdrive. Used j201, 2n2222, 2n2907 and 2n5458. I want to thank you for the scheme. Great sound! Previously collected your panzerfuzz. In Russia, the guitar forums, are often discussed your scheme. I wish you further success! People need to like you.
All the best!
Dmitry. Rassia.

thanks a lot, Dmitry! that means a lot, and I'm glad you are enjoying the schematics! I didn't know that anybody talked about any of my projects on Russian forums. that's very cool! if you could provide a link to the forums, I would love to see it. thanks, again, and please tell other Russian builders, that I am glad they like the projects!

H-FUZZ

2011-01-27T20:00:00.007-06:00

here's a pedal i built up for a buddy of mine the other day. he plays bass in the local chicago trio Hobo and Boxcar, and wanted something that he could use for bass as well as guitar. i built him up a circuit that i came up with based on the Fuzz Face/Wooly Mammoth model, that shines when it comes to double duty fuzz action. it's basically a tweaked fuzz face with russian GT309 transistors (a new fave of mine), that has the fuzz factory/wooly mammoth adjustable NFB gate control, an input gain pot, a max gain trimmer, and a LPF/switchable HPF adjustable tone control, similar to the Big Muff, that allows for guitar or bass functions. the mid shift switch allows anything from fat scooped bass, a dirty overdrive, or mid-heavy motorhead style grind. for guitar, it's capable of anything from monster thick doom tones to mosquito sixties style fuzz. topped off with some sweet vintage knobs, it's a great switch-hitter.

as an aside, after taking this picture, i realized that i wired the center pots up a little tight, so i simply switched the two middle pots around. now, if the nuts loosen up, the wires on the pots won't get pulled out so easily. a word to the wise- leave enough slack on your pots!

FOUR HORSEMEN OVERDRIVE

2011-01-17T04:09:00.002-06:00

well, i came up with another dirt pedal the other day. lately, i've been experimenting with mixing different types of transistors together to achieve new tones, and this one kind of takes that idea to the extreme. it's designed under the premise that the stages increase in breakup as it goes along in the circuit, but instead of using stages that increase in gain, different types of transistors are used that exceedingly distort as the the circuit progresses. for instance, the first gain stage is a silicon BJT. this is used to get a decent push going and a very slight amount of drive. next, is a MOSFET transistor, which like to distort a little easier, and in a bit more pleasing and richer way than the previous Si transistor. finally, there is a germanium stage, which of course loves to distort in a very full and heavy overdrive, especially when driven by the previous gain stages. the result is a very clear, yet complex crunch, that has a very nice character to it. to round things out, in the beginning of the circuit is a JFET buffer, which helps to increase the current, and gives a nice high input impedance for the guitar pickup to see. so in the end there is a total of 4 different types of transistors, each of which i tried to use to their optimum potential. hence the name, the Four Horsemen Overdrive.

the tone control is a variation on the SWTC, but it has an added pole for a steeper rolloff. the frequency point where the curve begins is rather high, so it is really more like a presence control- just taming the highest of frequencies, keeping the basic tone intact.

this circuit was spawned from a simpler design called the Nice Little Overdrive. you can see the evolution in the thread over at FSB.

http://freestompboxes.org/viewtopic.php?f=28&t=11745

here is the schematic as it is in the latest version.

here is a pic of a vero layout that i built up.

and here is a quick video i made on my iphone. the video is of the previous version without the high end rolloff presence control, and the bypass cap on the last stage, which adds a bit more gain. the voice of the circuit is basically the same, but there is a little bit more flexibility. of course the quality isn't the best, but you can get the idea! ignore the man behind the camera.

DIRTY BOOTS SOUND CLIP

2011-01-13T16:39:00.002-06:00

someone asked for a clip of the Dirty Boots, so I dug one up. HERE is a soundclick page by danielzink where you can hear it. if you go to the second song down, it's in the micro pedal demo. you'll hear a phaser first, then the DB. I haven't listened to the clip in a while, so I'm not sure how accurate of a representation it is, but I'm sure it's close. thanks, Dan!

MILITARY DIRTY BOOTS PICS

2010-12-28T12:54:00.001-06:00

here's a Dirty Boots I built up in an old tank communication control box. it's got some serious mojo(just for fun;))components, a switch for hi and lo gain, and a single volume knob. I like the idea of repurposing death machines for rock and roll. I should've bought more of these boxes when I had the chance! I've got one more, if anyone is interested.

SURVIVING THE APOCALYPSE

2010-12-22T13:21:00.001-06:00

WTF? more Aussies! when it comes to surviving the apocalypse, everyone knows the Australians know their shit. THIS video proves it.

ELECTRONICS AUSTRALIA PROJECTS AT OZVALVE AMPS

2010-12-14T21:52:00.005-06:00

I'm not sure what's up with all these posts about the land down under lately, but I recently ran across THIS great Australian site that has tons of information on Aussie guitar amps as well as building guitar amps and effects. included are a number of old magazine projects from EA. if you scroll down the page, you'll find schematics for fuzz, compressor, "phase vibrato" Leslie sim, and tremolo projects as well as a number amps. be sure to check out the rest of the site, as it's filled with some very cool articles and schematics, such as fsb forumite Phil's cool reverb project.

CUSTOMIZE YOUR POTS WITH 2 RESISTORS

2010-12-01T12:15:00.001-06:00

here is a very cool little pdf from elby electronics from australia. it includes some nice graphs and instructions on how to alter the taper and value of your potentiometers. it's an essential technique for making the most out of your controls.

LINK

MONA LISA OVERDRIVE LAYOUT

2010-11-21T15:46:00.005-06:00

i was asked to post a layout for the MLOD, so here it is. enjoy! i tried this circuit out with 2n5457, j201, and j309 fets. they all work fine.. the Q2 position is where most of the magic is. try different transistors for different tones. i enjoyed a 2n5210 with an Hfe of 250-300 there, myself. it had nice midrange content without sounding muddy. the images are at 600 dpi, a current limiting resistor for the LED has been added, and the gain pot can go up to 10k that's all you have. this circuit is a great sounding boost/light OD/ line driver/buffer. i hope you dig it!

take it easy!

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LAYOUT IS VERIFIED.

GREEN BOMB FUZZ AVAILABLE FOR PURCHASE

2010-11-04T21:42:00.002-05:00

i've decided to sell a limited number of Green Bomb fuzzes to anyone who wants to purchase one. each box will be a bit different, built old school style on tagboard, tuned by ear with whatever high quality components i choose to use at the time and true bypass. if you are interested, you can get ahold of me at apocalypseaudio(at)gmail.com. the price will be $150 each.

thanks!

abe.

AQUATAUR FUZZ RIDE

2010-11-04T21:28:00.001-05:00

fsb forumite, helmut shows off his version of the GREEN BOMB called the FUZZ RIDE on his website http://aquataur.at.tf/. he did a great write up, showing his additions to the basic GB circuit. helmut added in and output buffers, as well as a sag switch for other tonal possibilities. there are some nice soundclips uploaded there as well. make sure to check out helmut's other articles- they are all great reads. thanks, helmut!

MONA LISA OVERDRIVE

2010-08-27T18:54:00.003-05:00

alright, here is my latest offering to the faceless electronic gods of the global interweb. it's called the Mona Lisa Overdrive after everyone's favorite cyberpunk masterpiece, and dystopian premonition written by William Gibson. if you haven't heard of it, check it out! anyway, on to the the goods-

i thought i would build something that would turn on the guys that were into the lighter side of things- something different than my usual wall of fuzz tones. with the MLOD, you can get a heavy boost, or a light overdrive reminiscent of vintage microphone preamps. the fancy thing about this circuit is the lack of coupling caps in the audio path- something usually reserved for mic pres and hifi circuits. this lends itself to the "transparent", uncolored sound happening here. if you encounter any oscillation at the highest gain settings, simply raise the value of the 100 ohm resistor near the gain control to lower the amount of maximum gain.

as always, if anyone happens to put this on the breadboard, or if it sounds like something you might want to build, let me know, and i'll whip up a layout for it.

take it easy!

AUDIO NOISE AND GROUNDING- WATCH THIS!

2010-08-14T18:39:00.001-05:00

here's a VERY informative video on grounding that was posted by Paul Marossy over at DIYS. great video. everyone should watch.

TROUBLESHOOTING OPAMP CIRCUITS

2010-08-06T17:07:00.001-05:00

here's a cool little protocol for troubleshooting opamp circuits for the university of exeter physics department. it should be able to get you out of most opamp entanglements you get yourself into.

http://newton.ex.ac.uk/teaching/CDHW/Electronics2/troubleshooting.html

COOL STUFF FROM EE TIMES

2010-08-06T17:01:00.001-05:00

here'a some interesting things i found on the ee times site. an interesting article on audio myths, two audio amplifier design articles from john linsley hood's book, and another with a great vintage video of rca tubes being made. very cool stuff!

http://www.eetimes.com/electronics-blogs/audio-designline-blog/4033511/Audio-Myths-Workshop-video

http://www.eetimes.com/design/audio-design/4015905/Discrete-audio-amplifier-basics--Part-1-Bipolar-junction-transistor-circuits

http://www.eetimes.com/design/audio-design/4015906/Discrete-audio-amplifier-basics--Part-2-JFETs-MOSFETs-and-other-circuit-configurations

http://www.eetimes.com/electronics-blogs/audio-designline-blog/4033497/Vacuum-tubes-A-valve-video-a-tube-amp-modeler-and-a-joke

NATIONAL SEMI AN-779

2010-08-06T16:52:00.002-05:00

national semiconductor application note number 779 is a great resource on active, passive and switched capacitor filters. check it out!

http://www.national.com/an/AN/AN-779.pdf

as a bonus, here is a page on designing state variable filters for audio.

https://pantherfile.uwm.edu/msw/www/StateVariable/index.html

ALL ABOUT CIRCUITS WORKSHEETS

2010-07-22T09:02:00.024-05:00

this page from the ALL ABOUT CIRCUITS website has a multitude of worksheets for the electronic diyer to learn from and test themselves with.

http://www.allaboutcircuits.com/worksheets/index.html

there is everything from AC, to DC, to FETs, opamps, filters, and BJTs. even such simple stuff as ohm's law and caps and resistors. seriously, everything from atoms to active circuits!

for example, here is one of their "design projects". the objective is to help you in designing tone control circuits.

http://www.allaboutcircuits.com/worksheets/proj_tone.html

with these worksheets, there should be no excuse not to have some serious kung fu!! hiiiiiieeeyahhh!!!!

CIRCUIT SPLINTERS NO.2 - SZIKLAI PAIR BUFFER AMP

2010-07-22T03:04:00.026-05:00

ok, here it is, as promised, AA's Circuit Splinter No.2! but first, a little warning- i am not an electrical engineer, nor do i claim to resemble anything close to one, here or on television. please take everything i post as just what it is- the off kilter ramblings of a misinformed diy enthusiast- nothing more, nothing less. i'm trying to learn just like you.

now-

we are continuing our limited look into DC coupled buffers and amplifiers. in this case, a JFET/BJT Feedback Amplifier. this amplifier configuration is known as what is called a Sziklai Pair, otherwise known as a compound transistor, which is similar to a darlington pair, and sometimes called a compound darlington. this wikipedia article goes into the sziklai pair a bit more, such as how they are often used in discrete solid state output stages.

http://en.wikipedia.org/wiki/Sziklai_pair

here is a great article as well from answers.com-

http://www.answers.com/topic/sziklai-pair

in this article is a description of the feedback involved-

http://www.angelfire.com/planet/funwithtransistors/Book_CHAP-5.html

and finally, a jensen transformers app-note for a piezo buffer amp-

http://www.jensentransformers.com/as/as098.pdf

basically, what we have done that is different here from the last edition of Circuit Splinters(in my limited understanding), is to reduce the amount of feedback from one stage to the next. previously we had an infinite amount of feedback, which gave us a voltage gain of 0. by inserting R5 into the picture, we raise the resistance, and therefore lower the amount of feedback. in doing this, the gain of the stage rises. as you can see below, the gain of this stage is equal to the ratio of R3 to R5. so, lower R3, or raise R5, and the gain goes up. the circuit below has R3-470, R5-4700, so 4700/470 = a gain of 10. the great thing about this kind of stage is that you have a high input impedance from the FET, a buffered output, and you get voltage gain instead of just current gain as in a classic buffer. remember that R2 may have to be adjusted to 1/2 your supply voltage on the drain of Q1 for the proper amount of headroom.

i think that this circuit tends to sound best when used in a "clean" gain type of stage, with just a slight amount of breakup. never the less, many different adjustments can be made. instead of R3, put a large bypass cap, and move R3 to the emitter of Q2 for more gain. try different bypass caps for different frequency responses. bypass Q2's emitter. if you adjust your bias circuit, you can use a bjt for Q1. try a Ge pnp for Q2. see what happens when you put a small cap from the source of Q1 to the collector of Q2.

here is an example of an RIAA circuit that uses this configuration. you can see what has been done to tailor the frequency response of the stage for the RIAA curve using RC filters in the feedback section.

(click to enlarge)

here's a version from John Linsley Hood that uses a bootstrapped input-

(click to enlarge)

here's another one that uses a bjt for Q1, and has an interesting baxandall-style tone control based on feedback as well. note the bias configuration for the BJT input transistor.

(click to enlarge)

as always, if anyone out there has any real knowledge they can share, feel free! the sky's the limit. go nuts. have fun. take it easy!

MORE VIDS - JFETS

2010-07-04T10:10:00.003-05:00

here's more electronic theory videos, this time JFETS.

SOME INTERESTING TECH VIDEOS

2010-06-24T08:14:00.003-05:00

here's a few interesting audio electronics related vids i pulled off the net. i haven't had a chance to check them out yet, but i thought it couldn't hurt to post them anyway. check out the other videos on the channels of the posters, there is some good stuff there as well.

cheers!

gigelmargel's CRANKED AC

2010-06-24T00:39:00.003-05:00

here is a pic of an assembled cranked ac pcb put together by FSB member gigelmargel. looks great, and thanks for verifying the project! the full project files can be found here-

http://apocalypseaudio.blogspot.com/2009/11/wampler-cranked-ac.html

ELECTRONICS CALCULATORS

2010-06-21T13:08:00.012-05:00

here's number of handy electronics oriented calculators from around the web. enjoy!

common emitter voltage divider calc
http://www.diystompboxes.com/biascalc/vdbias.html
big muff bias calc
http://www.diystompboxes.com/biascalc/bmbias.html
fuzz face bias calc
http://www.diystompboxes.com/biascalc/ffbias.html
electronic math helper page
http://www.diystompboxes.com/analogalchemy/emh/emh.html
opamp gain calc
http://www.csgnetwork.com/opampcalc.html
LED resistor calc
http://www.csgnetwork.com/ledsingresistancecalc.html
capacitor calculators
http://www.csgnetwork.com/capacitorinfoconverters.html
ohm's law calc
http://www.csgnetwork.com/ohmslaw.html
parallel resistance calc
http://www.csgnetwork.com/parallelresistcalc.html
transistor sim and calc
http://www.csgnetwork.com/transistorcalc.html
sound studio and audio calculations
http://www.sengpielaudio.com/Calculations03.htm
capacitive reactance calculator- what's the resistance at this frequency of that cap?
http://www.electronics2000.co.uk/calc/reactance-calculator.php
electronics2000 calculators- a bunch of em!
http://www.electronics2000.co.uk/calc/
-many calculators for amplifiers are available at Amp Books. including these--
cathode bypass cap calc
http://www.ampbooks.com/home/amplifier-calculators/cathode-capacitor/
coupling capacitor value
http://www.ampbooks.com/home/amplifier-calculators/coupling-capacitor/
bright boost cap calc
http://www.ampbooks.com/home/amplifier-calculators/bright-boost/
grid stopper resistor calc
http://www.ampbooks.com/home/amplifier-calculators/grid-stopper/

SOLID STATE GUITAR AMPLIFIERS BY TEEMU KYTTALA

2010-06-04T04:20:00.003-05:00

clicking on the title of this post will send you to a download page for the book SOLID STATE GUITAR AMPLIFIERS by TEEMU KYTTALA. trust me, DON'T be dissuaded by the title! even though sold state amps are kind of like kryptonite to many tone whores, this book contains tons of info that can be extremely useful when designing audio circuits. explicitly the preamp section, which is full of heaps of goodies that can be used for stompbox design. it's written in a simple, yet concise style that tells you just what you need without getting bogged down by too many details. also, the power supply and power amp sections have everything that you would need to build an ss amp. this book really is a great resource that i will be diving into head first. i believe teemu goes by teemuk on the forums, so make sure you give him a hearty thank you if you download the book!

THANKS, TEEMUK!!!

IBODOG'S GREEN BOMB VERO

2010-05-27T12:58:00.003-05:00

i just thought i would post a link to ibodog's green bomb vero layout over in his diys gallery. the layout is verified, and there are a number of other nice layouts over there, too. click on the title of this post for the link. thanks, ibo!

MOSRITE AMPLIFIER ONBOARD FUZZRITE SCHEMATIC

2010-05-25T19:04:00.001-05:00

continuing right along with all things FuzzRite, an anonymous donor supplied me with a very rare Mosrite amplifier schematic to post over at FSB. it contains a schem for the onboard FuzzRite circuit that came stock with the amplifier. as you can see, it is a bit different than the FuzzRite schematics that we know of, kind of a mix between the Ge and Si versions, as well as having a few different values, a 220pF compensation cap on Q1, and of course the fact that it runs on 33V. i hope you guys enjoy this rare treat!

CIRCUIT SPLINTERS NO.1

2010-05-17T22:56:00.003-05:00

So it's been a while since i've posted here, so i thought i'd actually post something worthwhile! here is the first episode of Apocalypse Audio's CIRCUIT SPLINTERS. i hope to post little circuits that can be helpful when designing your own stompboxes- like gain stages, tone controls, filters, clipping arrangements, etc. i'll try to keep the things i post relatively new, because we all know places like geofex and amz have this kind of shit locked down, and i really don't want to post a bunch of circuits that you can find elsewhere on the more venerable stompbox sites on the net. most of the stages i'm going to present are things that i've culled from the various books and websites that i have found, and occasionally something that i have come up with or modified to my own liking.

the first circuit i am going to present is the high impedance input JFET/BJT buffer circuit below.

this is a rather common cookbook circuit that you can find in books and on the net, yet personally i have yet to see it in stompbox circles, so i thought i would post it. it uses an npn JFET DC coupled with a pnp BJT . the FET allows a a much higher input impedance than a BJT normally would. R1 could realistically be anything from 1M to 10M, this will only really affect the low end coupled with C1(which i have left open for you to decide the value). the BJT is "inverted" so that a pnp transistor can be used with a negative ground circuit, for what i presume is for it's lower noise specs. i haven't measured the output current of this configuration versus a single FET buffer, but that could be something i'll do in the future and report back. the real reason i am posting this buffer is because it can easily be turned into an amplifier stage, which can subsequently be used for a sweet booster/overdrive. all that and more in the next installment of CIRCUIT SPLINTERS!

bonus question: anyone want to tell me where to place the resistor in order to turn this buffer into an amplifier?

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here is some info from RG Keen on the circuit-
http://www.diystompboxes.com/smfforum/index.php?topic=71592.0

GREEN BOMB PICS AND CLIPS

2010-03-16T18:27:00.002-05:00

brothers and sisters! you know it's time to...

show you some pics!

my buddy Double A picked up Green Bomb No. 1 and has been putting it through it's paces lately. he has reported back that the intense fuzz sounds garnered from this machine are indeed up to his high demands, and was kind enough to post a nice clip as well as take some pics of the this sucker for me. (i really hafta get a camera soon!) he started up a little myspace page that will be focusing on different pedals, and he chose the GREEN BOMB as entry number one! check it out, there is a sweet sample of A-Double hashing out some nasty Davie Allen licks!

HERE

he was also kind enough to send me a few pics as well. here are a couple of the best-

IBODOG'S GREEN BOMB FUZZ SOUND CLIP

2010-02-28T05:58:00.001-06:00

click on the title and you will be treated to a great clip of the GREEN BOMB FUZZ made by FSB regular ibodog. many, many thanks to Sir Dog for his excellent contribution. it shows off many of the middle range tones of the GREEN BOMB. hopefully, i will soon make some clips of the more extreme end of the palate as well for you all to enjoy.

thanks ibo! you rock. i am in your debt.

TOECUTTER V.1 REV.C PCB LAYOUT

2010-02-25T00:05:00.005-06:00

recently there was a request for a Toecutter pcb, so i made up this version of V1 because i still think that it is probably the best sounding version. it isn't verified, but it is checked in eagle, so it should be good. i hope you guys enjoy it, and be sure to let me know if you get it built!

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just a little tip- for a wider variation in the gain control use a larger pot- say 500K. personally, i like to keep it up around the upper end of the gain range, so 100-250K is usually what i like to go with. also, a 100K volume pot will brighten up the sound a bit, and changing the 4K7 resistor to 10K will add more gain, but i think it loses some of it's crunchy magic.

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spencerpedals made this great post about The Toecutter over at FSB, i thought i should share it-

"Re: RnFR- The Toecutter

by SpencerPedals » Thu Feb 25, 2010 9:42 pm

Finally got around to breadboarding this with some low-leakage pirated germaniums, house numbered so I have no idea exactly what, and it will rattle your fucking skull. I've liked the clip since I heard it, but didn't have a closet full of parts. If anyone's ever heard the stuff from Slow Burn, the tones you get are almost identical. I always test pedals through an old school solid-state Crate and then if nothing explodes, I run them into my Ampeg V4. This thing definitely comes alive in the later (as most do) and with tuning dropped to C, is probably even lethal to small animals. I don't have any pets, so I can't say for sure. Actually I do have a snake and I didn't check, but she may very well have perished. I have V1.1 on the breadboard but with a 500K gain pot from V3 and used Q1 and Q2 in the 80's hFE and Q3 in the 120's. I'll be seasoning to taste over the next few days/weeks and report what I settle with. And if you're not a fan of growly loudness, it actually sounds very sixties fuzz when you turn the gain down and screw with the bias. Not my territory with this one, but versatility is there. More to come."

great stuff! glad to hear he's diggin it!

ANYBODY OUT THERE?

2010-02-22T19:12:00.001-06:00

hey you slags! if anybody is actually reading this thing and getting any enjoyment, please let me know! i mean, even if nobody read it, i'd still do it for my own sake, but it sure would be nice to know that someone is getting something worth while out of this. if there is anything you'd like to see more of, bring forth your brainiac-size ideas, and i'll take them into consideration. you can also sign up to become an official follower on the lower right as well.

or maybe i'm the only one left on the planet...... just me and my robot.

AWESOME RUSSIAN GEAR SITE!

2010-02-22T19:01:00.004-06:00

my buddy jrod over at FSB turned me on to this killer vintage Russian guitar and effects site. click on the title, and you get a babelfish translated version of the site. i've barely gotten into it, but it looks like it's filled with some freaky psychedelic machines and cold war rock and roll ingenuity. check it out!

he also found on the same site, a different version of the KAZAN BOOSTER that was featured in one of the first posts on APOCALYPSE AUDIO. the difference with this one is that there are diodes sprinkled around in the signal path, which is a rather odd design technique. the only other place i've seen something similar is in Joe Gagan's Vulcan distortion. this can be found in the ANALOG ALCHEMY LINK on the right of the page. he described it as a sort of limiter to prevent hard saturation of the transistors. it sounds like a neat little trick- i might have to give it a shot sometime.

FREESTOMPBOXES.ORG RSS FEED ADDED TO APOCALYPSE AUDIO

2010-02-22T17:56:00.004-06:00

if you look over to the lower right, you'll see apocalypse audio's new freestomp rss feed. now you can keep up with the coolest stompbox forum on the planet at a glance. you'll never have an excuse again to not know what's inside that new, totally original, totally awesome electra copy that yer favorite solder jockey has been working on nonstop for years before it's release. or why not get in a heated debate about the "sound" of capacitors? it's all there. and i mean "all"! i'd be surprised to see a production stomp by a major manufacturer that hasn't had it's schematic and inner workings fully analyzed. join in the fun! we don't have much time before we are all turned back into dust anyway.

GREAT BOOKS TO DOWNLOAD

2010-02-22T17:45:00.003-06:00

click on the title and get sent to a bevy of the highest quality audio electronics books for download. now you can use your original 75 dollar copies for kindling! just hurry and get 'em before they decide to get their electrilives cut short by the evil horde of junkpile robots from greedtown.

GREEN BOMB FUZZ TAGBOARD LAYOUT

2010-02-19T04:49:00.002-06:00

here's a tagboard layout for the GREEN BOMB that i built up today. it's got a great deal of variation due to the wide range of gain and the phase cancellation. lots if tones, but it always has that great FuzzRite buzz. it's going to be a fun fuzz when i get it fully built.

GREEN BOMB FUZZ

2010-02-16T19:04:00.004-06:00

here's something i was working on the other night. it's a revved up mosrite fuzzrite based off of gus's gusrite circuit. i basically juiced up the gain even more, did some stabilization and frequency response adjustments and added a nfb based tone control to add even more weird phase shaping possibilities than what was had in the original. it's basically like a fuzzrite on steroids. i'd suggest a mid gain transistor for Q1 and a high gain for Q2. different transistors do different things, so it's worth trying out some different ones. oh, and it can totally do that spirit in the sky thing perfect! when you turn the gain all the way up you get that ratty almost misbiased thing that greenbaum had going on in his onboard fuzz. back the gain off and rattyness goes away. this thing is my new go to for crazy psych madness. if you want more of a honky sound, lower the transistor gain a bit. i'll probably try and do some more tweaks in the future, and i'll post them when i get a chance.

also- i've got a tagboard layout that i'll post when i get it verified. ;]

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here are the schematics from Gus's rite fuzz and the mosrite Fuzzrite for reference. if the owners have a problem with my posting them here, i will gladly take them down.

also, i was asked on FSB to describe the added tone control. i tried to explain it to the best of my ability. if anyone has anything to add, please, feel free.

the fuzz control on the fuzzrite works by adding the output of the first stage, an out of phase signal, with the output of the second stage, in phase signal. this is what produces some of the thin, hollowed out, phase cancelled sounds that the fuzzrite is known for. the shape control takes the non-inverted output of the first stage, with the output of the second stage, which also gets mixed in with the output of the first stage with the fuzz control. the shape control has a low pass filter due to the .01 cap to ground, so when when it's negative feedback takes place, it only cancels out the lower frequencies and leaves the highs. with this control you are still able to get the brite, zippy sounds of the original fuzzrite, but are now also able to get the thicker sounds of gus's ritefuzz- all through the same negative feedback techniques similar to what was used in the original fuzzrite!

FEEDBACK IN AMPLIFIER CIRCUITS

2010-02-10T10:58:00.005-06:00

click on the title of this post, and you'll get directed to part of the excellent Fun With Transistors Page on amplifier feedback. feedback can be used to increase linearity of the output, curing oscillation, reducing gain, and tonal shaping among other things when used in amplifier stages. usually when we speak about feedback, we are talking about negative feedback in amplifiers. this is accomplished by adding an out of phase signal to the input of a gain stage, often by taking the output of an inverting amplifier. the webpage takes an in depth look at different types of feedback complete with diagrams and equations for those that are so inclined. check out the rest of the site as well as the Fun With Tubes page which has some great info, too.

CIRCUIT SIMULATOR JAVA APPLET

2010-02-10T10:46:00.001-06:00

if you click on the title of this post, you'll get directed to the instructions page of a cool little circuit simulator program. while i doubt that this this is nearly as in depth or accurate as something like the SPICE-based programs out there, it's a fun little program that runs on JAVA, and it can definitely help the learning process along. not too mention, it is much easier to learn. there are a number of circuits that have already been put together that you can easily adjust and add to as much as you like, or of course you can start from scratch. i had a lot of fun messing around with a gain stage that i have been trying out as of late, seeing how the output changes with component values. it's a lot of fun, and is a great learning experience as well.

JACK DARR'S ELECTRIC GUITAR AMPLIFIER HANDBOOK

2010-02-10T10:31:00.002-06:00

HERE is a page from Paul Marossy's website with a number of downloadable chapters from this great book by Jack Darr. there is lots of info, including tube and early solid state, that is guaranteed to be helpful for anyone out there looking to get into this of thing. check it out, it's an excellent book!

BUILD A LAMP LIMITER

2010-02-10T10:15:00.004-06:00

i recently decided to start monkeying around with some tube amps that i have aquired over the years, namely a couple of bogens, a bell pa head, a couple of small voice of music phono amps, and my big ol traynor yba-3. a great gadget that is a must have for beginning tube amp tweakers is the Lamp Limiter. it allows you to power up the amp while being able to tell if the amplifier is drawing too much current off of the mains. if there is a short in the amp, the lamp will light up brightly. here is a nice article from a UK radio sight about the lamp limiter, and a cool thread about "reading" the action of the bulb.

LAMP LIMITER
THREAD

these UK articles recommend a 100w bulb, where as this article from R.G Keen says that a 25w or larger bulb will do.
GEOFEX ARTICLE

a lamp limiter is a great way to help the learning process when working on tube gear, and hopefully can keep you from needlessly blowing anything up!

DIRTY BOOTS TWEAKS

2010-01-29T00:08:00.003-06:00

jrod over at FSB is planning on building a DIRTY BOOTS, and asked me what kind of tweaks could be made. it's really a highly variable circuit, and can be tailored to your specific tone very easily. here's what i wrote to him-

there is a lot of tweaking that can be done to the DB. you might want to lower the collector resistor on Q2 as it is a bit voltage starved. if you want less drive, increase the resistor in between stages, or take out the bypass caps on the emitters. also, you might want to increase the collector resistor on Q2 as it is kicking out pretty much full gain, and that can make it a bit noisy. maybe try 1K. it all depends on what you want. if you want it brighter, lower the value of the compensation cap from C to B on Q1 or put a 47K resistor in series with the input. adjust the in and out caps for low end. it's a really easy circuit to tweak, so i would just put it on the breadboard, and figure out what you like for your amp.

TRIODE FUZZ NO.2/ AMZ SIXTIES STYLE FUZZ TAGBOARD LAYOUT

2010-01-03T08:15:00.004-06:00

a while back, i posted this little article on a couple of fuzz circuits i found on the triode electronics site. the first is very similar to a fuzz face style circuit, where as the second is a little bit different. it has what appears to be an emitter follower into a kind of dc coupled complementary gain stage pair. very much similar to the jordan bosstone. here is a link to the original article.

http://apocalypseaudio.blogspot.com/2009/05/triode-fuzz-1-2.html

while surfing around the voluminous pages of Jack Orman's AMZ effects website, i saw something that looked a little familiar.

http://www.muzique.com/schem/sixties.gif

it seems that the triode fuzz and the amz sixties style fuzz are one in the same! most likely, this is an old circuit taken from one of the many electronics "cookbooks" from back in the day. regardless, i've heard from a good source that it's supposed to be a great sounding circuit, so i decided to draw up a layout- this time for tagboard construction. tagboard, eyelet board, or turret board can be a fun way to do your circuit board construction for a change. there is no etching or drilling to be done, and you get to use those nice sounding axial foil caps that would've never fit on your pcb circuit. i really like using this particular tagboard that can be found at weber as well as apex jr. for very reasonable prices.

https://taweber.powweb.com/store/fb-v.jpg

it has 3 different solder points per tag that makes it very easy to find holes for your passives, actives, and wire without running out of space. the layout i made for the triode/sixties fuzz circuit was made specifically for this type of board, but you could easily adapt it to other types of tagboard out there. i haven't built it yet, but i do plan to in the near future. as always, let me know if you decide to build it yourself.

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i got this thing on the breadboard, and had a rough time getting it to bias properly. i'm going to try and figure it out, and i'll post anything i find.

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due to problems with this circuit biasing correctly, i have pulled the layout. i'll post a new tagboard layout for a better design shortly. looking at this one with a more informed set of eyes, there are many things that could be done differently to make this a better design. i'll post another tagboard layout for a proper fuzz circuit once i get it checked and verified.

WHO RUNS BARTER TOWN???

2009-12-18T13:45:00.002-06:00

some additions to the MASTERBLASTER article have been added, including a new layout and some new mod ideas. you will be redirected to the article by clicking on this entry's title.

WAMPLER - CRANKED AC

2009-11-29T15:07:00.004-06:00

recently while browsing a certain clone kit site, i stumbled across the schematic for brian wampler's cranked ac design. having been on a serious ac kick a while back, i was never able to find the schematic, so this was kind of a cool find. the cranked ac at first looks like your run of the mill jfet type distortion box until you notice that wierd parallel fet configuration. ecaxtly what this is supposed to do to the sound i don't know, but it is a rather interesting little tweak. i'm sure that this could be adapted to just about any transistor type, and wonder if it has any of the same kind of properties as stacking ic's.

i redrew the schematic and made up an eagle verified pcb layout which should work ok. if anyone gets it built please let me know . you can keep up with all of the latest on this subject HERE.

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LAYOUT IS VERIFIED!

LISSAJOUS FIGURE VID

2009-11-28T12:07:00.003-06:00

browsing the really cool EXPERIMENTALIST ANONYMOUS BLOG, i found this great video of a LISSAJOUS FIGURE portrayed on an oscilloscope. from what i gather, a lissajous figure can be generated using a scope by injecting one wave ionto the x axis, and another onto the y axis. summing them together, you get this 3D effect. the maker of the video put the left channel through the x axis, and the right through the y, all the while tweaking multiple effects. as i finally picked up a scope recently, i find this sort of thing fascinating. unfortunately, the cheapo 40 dollar scope i got only has a single channel, so you won't be seeing any lissajous figures from me in the near future.

SOME COOL PARTS SOURCING SITES

2009-11-27T06:31:00.001-06:00

here are a few kick ass sites to source parts on the cheap. the first is EVITA. they are a great source for any russian parts that you might want, and are even cheaper than what you can find them for on ebay. plus you don't have to buy a box of 100 of a single type, you can mix and match as you please. i have heard that they have reasonable shipping, and EVITA has all of the datasheets available for download on there sight, so you have some idea of what you are getting into.
as you can probably tell, i have a serious passion for these russkie germanium trannies, as many types are about as consistent as any silicon transistor out there, and unlike euro, american, or japanese trannies, many types have absolutely no leakage. the consistency of russian ge transistors is pretty much unparalleled around the world. i think this must be due to the fact that the soviets were producing germaniums well into the 80's where other sources had stopped long before. also they used them for many military uses as well, so their standards were set very high. you can tell the transistors and other parts meant for military use as they have a small diamond printed on the side.
along with transistors, there are many excellent russian teflon, paper in oil, and polystyrene capacitors offered at EVITA, so if you have an urge for cheap, quality soviet parts, now you don't have to be a slave to ebay.

if you have ever built an analog delay, you know how hard it is to source bucket brigade delay chips. you can end up paying a hefty price for what may end up being total counterfeit crap. you can go to a parts sourcer, but there may be a large minimum order that puts buying the parts well out of your price range. well, i recently was turned on to UTSOURCE, who source hard to find, out of production parts with very small minimum orders and good prices to boot. give em a shot if there are some rare chips you can't find.

lastly, is TEDDS.COM. they have lots of cool vintage capacitors and other parts with only a ten dollar minimum. also, they have pics of every cap in their inventory so you don't have to have every model number memorized. good stuff.

EFFICIENT CALCULATOR USE FOR ELECTRONICS FORMULAE

2009-11-26T10:20:00.001-06:00

HERE is a great post by electronics wizard Tonmann over at the circuit workshop forum. it breaks down and totally demystifies the process of working on electronics formulas. it's a great little tutorial, and hopefully, tonmann will have his larger tech tutorial done soon.

OPAMP BASICS

2009-11-26T09:47:00.002-06:00

mystified by that tube screamer? in a conundrum over the klon? THIS course at Elliot Sound Products has all of the basics about opamps covered. all the common configurations, power applications, filters, and formulae are there for the taking. they have a shitload of other great articles and projects over there too, so be sure to check out the rest of the site.

FREE ELECTRONICS BOOKS

2009-11-26T09:39:00.004-06:00

HERE and HERE are great sites with tons of free electronics based e-books. lots of info on tube, solid state, electronics theory, hifi and more...

3PDT DAUGHTER BOARDS

2009-11-08T15:24:00.001-06:00

recently i've gotten right sick of trying to jam my nice, thick, 22 gauge, solid core wire into switch contacts. many times i'd end up marring the insulation, or just not liking the appearance. a remedy was to design a daughter board to connect all of the wires to the switch. after a bit of talk with my friends over at FSB, i decided to expand on the idea, and built a few different versions. V1 is a simple board with connections for each lug on the switch. V2 has a resistor added for limiting the power to the LED. version 2.1 adds a pad for connecting DC and the other side of the LED. finally, V3 adds to this a spot for a power filtering electrolytic capacitor, and polarity protection diode. in the future i may add more designs, possibly adding R.G. Keen's MOSFET polarity protection scheme, and a voltage divide for use with op amp circuits. there has also been some talk of making a group buy for printed PCBs. we'll see if that ever comes to pass in the future. you can check out all of the layouts and keep abreast of the latest news HERE.

MONTARBO PB-2 FUZZ SECTION

2009-11-06T05:24:00.004-06:00

hey if anyone is out there, sorry it's been so long. been kinda denying the blog love lately, hope to get back into it with some cool stuff to add.

here is a little italian fuzz circuit that i thought looked interesting. it's from the montarbo pb-2 fuzz/phaser combo pedal. i like the negative feedback diode configuration. at first it looks a bit like a muff, but there are some differences when you look closer. you can see that the diode loops are separated by capacitors effectively isolating them from the DC that is used to bias the transistors, where as in the big muff, the diodes have their own dedicated blocking caps, filtering the frequencies to be clipped. also, there is a 47K resistor to ground on the first tranny's diodes that may introduce some harsher clipping by pulling the diodes closer to earth. it looks like a fun little way to adjust clipping, and i plan on giving it a shot in the future. if anything cool comes of it, i'll be sure to let you know on the blog.

cheers!

ELEKTRATONE'S DIRTY BOOTS

2009-08-26T02:15:00.002-05:00

FSB forumite elektratone built up this cool rust finished version of the dirty boots a while ago. i thought it was about time he got some fame on the blog. it definitely looks like this thing's been through the apocalypse and back!

FREESTOMPBOXES.ORG MONTHLY CIRCUIT ANALYSIS

2009-08-24T01:46:00.003-05:00

the first installment of the FSB Monthly Circuit Analysis is up and running! check out the dirt on the Maestro Fuzz-Tone. there are circuit analysis, links to clips, patents, experiments, explanations, and tons of other cool stuff regarding the first ever fuzz box made. hopefully this will turn into a long standing tradition at FSB, as we explore the other creations throughout the pantheon of guitar effects. check it all out HERE.

COLORSOUND DEALER BOOTH

2009-08-07T14:26:00.005-05:00

i just thought i'd post this great pic of the colorsound booth from a convention in the early seventies. it was so cool, i just had to show off those funky displays. enjoy the shag!

APOCALYPSE AUDIO - PANZER FUZZ

2009-07-20T10:27:00.008-05:00

my latest creation is an uber-high gain fuzz-tortion designed around the soviet GT308B germanium transistor. since this seems like one of the more common russian germanium transistors that people buy, i thought it would be a good candidate to include in my next project. the 308B has a gain that usually hovers around 75 in most specimens that i have seen, except for some batches marked with red dots that have a gain of around 20 points less on the Hfe reading. as with most other soviet Ge's, their leakage is pretty much nil, this allows for excellent stablilty, easy biasing without trimpots, and no need to do tedious gain/leakage checks. i thought the 308 would be the perfect candidate to design a high gain fuzz around because of it's relatively high gain compared to other russian Ge's, and i haven't done anything along those lines since the Toecutter, which although it is doomy as hell, it is in itself not all that terribly high gain anyway.

the controls of this guy are as follows- gain, lo drive, hi drive, tone, and volume. the lo drive control is basically a full range gain control for the 2nd stage, and the hi drive control is i gain control for the 3rd stage that is concentrated only on the high frequencies. with all of the gain and drive controls turned up, you get an all out doomy grind with plenty of bite for on the top end. rolling back the gain control gives you a great crunch tone that i would describe as medium-high gain. the tone control is a heavily modified version of one that i saw on the AMZ site. i added 2 more caps, and adjusted all of the values for a nice even sweep. turning it all the way up also brings in a little bit of low end as well, so you get what sounds like a little dip in the midrange, too- adding to the metal tone of circuit. don't get me wrong though- this isn't one of those ultra-scooped metal zone P.O.S.'s. this thing has a ton of low end and has been tuned to have a bump in the high mids as well in order to cut through the mix and add some nice grind to the tone.

i did this write up of the basics of the schematic for culturejam's new circuit design forum circuitworkshop.com.
it can be found HERE.

the input cap(.033) was chosen to roll off just the bottom end of the input signal, there will be plenty more of that to come. the first stage is a basic booster using feedback biasing(1M resistor), and a .47 uF bypass cap for more gain throughout the full frequency range of the guitar. the emitter resistor(1K) was chosen to limit the amount of output from the first stage, and the 470pF cap rolls off some highs and stabilizes any oscillations that might happen.. next we have the gain pot(500K) and a 2K2 resistor setting the minimum amount gain available. the .01/220K combo allows highs to pass easier than lows trimming some of the fat off of the boosted signal. stage 2 is biased the same, as is stage 3. i find this technique of biasing easy and simple, allowing for fewer components as well. the .047uF cap rolls some high end off of this stage. the lo drive pot is a 10k pot going through a 47uF cap to ground. this isn't really just low end getting boosted per se, more of a full range gain control for this stage, but with the lows rolled off by the .o47 cap it definitely has some of that feel to it. the 100K/.1uF combo are doing negative feedback duty, reducing the overall gain a bit, as well as taming some noise and adding stability. next, the .0047 cap is more low pass filtering, and the .068 is hi pass,interstage coupling, and DC blocking. stage 3 also has some more high end filtering grom the .0022 cap to the 9V rail, and the bias values have been tweaked by ear a little. the hi drive pot is a 1K connected to ground through a 100uH inductor. turning this up adds a decent amount of sizzle to the sound. the 680/.1uF to ground were added to round out the frequency response of this stage a bit. the tone control is a tweaked version of jack orman's swtc2. i changed some values and added the .0033 and .01 cap to ground. the final .001 cap is rolling off a bit more of the very top end. finally the volume control has a 2K2 resistor to ground to limit it's lowest value. the mosfet and 1M resistor are there for reverse polarity protection, and the 100uF cap is for power filtering.

attached is a pcb layout, that is of yet unverified, but it has been checked in eagle, so it should be good. i'm going to try and get some clips done soon- they won't be the highest of quality though, but you should be able to get the idea of what is going on. hope someone out there can give this one a shot- it's really a killer!

XXXXXXUPDATEXXXXXX it looks like the size printed on the layout is a bit small. if you measure it out to that size, then increase by 10% you'll be perfect. sorry about that!

freestompboxes manifesto

2009-07-07T12:48:00.001-05:00

i thought i'd print this bit of text that explains how and why my favorite forum- freestompboxes.org- was created. here ya go, the Freestompboxes Manifesto!

Freestompboxes.org Mission Statement (June 17th, 2007) Another Forum? It really takes nothing to set up a forum nowadays... No money, no knowledge, just a borrowed computer will do. There are more then plenty of them on every subject all over the internet. Probably rightfully so, because newsgroups and forums are the heart of the internet: people from all over the world with the same interest have the opportunity to exchange ideas. With libraries abound, the internet did not do so much of spreading the canon of official canonical information. Rather, it turned out to be a great medium for the exchange of underground stuff. Building your own guitar effect stompbox is a prime example. Stompbox project Info on the internet Most of the circuits have been around since the beginning, but mostly in DIY magazines and they never really caught the guitarists' eye. They just walked in and grabbed their Guitar Player magazine. The online guitarist googling for 'vintage stompboxes' nowadays is bound to meet the DIY stompbox community sooner or later. And if you are true tonefreak rather then a show-off name dropper you get very happy at the thought that you can build your own 'boutique' stompbox and tweak it to your own taste for a fraction of the money you would pay for a boutique box. Backlash of the DIY pedal craze Big commercial pedal manufacturers are dropping their prices like they're hot, boutique pedal makers are getting nervous and begging the diy community to safeguard them certain commercial death. Or so they think... Recent turbulences and censorship of certain commercial schematics (although they are all over the net) has caused great upheaval at the mother of all stompboxsites, aron's diystompboxes.com causing some 'heretic' discussion to flee to the kind German Musikding.de forum. Copyright, Patent and more Of course often the artwork and the graphical layout of the pcb of effect are protected, but redrawing or tracing a circuit is by no means illegal. Patents on effects do exist, but they are not some common. Most of them have expired by now. There are some examples here on the forum, so do check them out in you are interested. Maybe this quickly setup board can provide a space for unabridge, free discussion about any stompbox design.

TRIODE FUZZ 1 & 2

2009-05-04T05:17:00.005-05:00

here in chicago we have a cool electronics shop called triode electronics. in the amazing mess that is triode, there is a virtual plethora of parts and supplies for the DIY enthusiast. on the store's website there are a number of interesting circuit schematics and articles, and i found these two little fuzz circuits there. one is very similar to the fuzzface, and the other looks like a pretty interesting sixties style fuzz box. i'm not sure where they come from, but they look pretty cool, and are worth giving a try. who knows, it could be the next fuzz factory!

2, NO, 3! NEW DIRTY BOOTS VEROS!

2009-04-21T18:58:00.005-05:00

dudes! made up a few new veros for the db. the first one is a small layout for box caps and radial electros for you guys that like those little baby boxes. the second one is for axial caps vintage style and specifies the specific type of caps that i have been using for my builds. of course, sprinkle your mojo to taste. i'm callin this on v5.2 because of the added reverse polarity protection diode as well as a limiting resistor for the pre control. haven't decided at the exact value for that one, most likely around 50-100K, or just put lug one straight to ground like before. the third one is just stupid small. i call it rev2. good luck you masochists! take er easy!

GARY HURST MK1 VERO LAYOUT

2009-04-17T00:27:00.005-05:00

here's a layout i made up today while trying to stay awake at one of my corporate gigs. it's for gary hurst's version of the tonebender mk1. a kind of finnicky crcuit, it is said to work best with leaky trannies, we'll see when i throw it on the old breadboard later. looking forward to building this one up after i heard some killer clips at the DAM forum. the layout can be easily changed to vintage specs as well, if that's the one you are after. the schemo can be found HERE.
XXXXXXUPDATEXXXXXX layout is now verified! try a 1M resistor in place of the 2M2 for more output.

here is a shitty pic of the verified board.

i've been promoted!

2009-04-15T15:23:00.004-05:00

the fine minds over at freestompboxes.org have deemed me worthy of modhood! that's right, yours truly was dubbed moderator over at the coolest diy guitar effect pedal site on the interwebs! holy fuck, i'm cool! now seriously, all you slags watch your back cuz there's a new man with a badge in stomptown and he ain't takin no prisoners. search first, or straight to the klink witcha!!!

JOE DAVISSON'S SIMPLE CAB SIM VERO LAYOUT

2009-03-26T04:32:00.003-05:00

i made up this layout and built this up tonight so that i could work on fuzz designs in my headphones late at night. layout is verified.
schematic can be found HERE.

TONE FACTOR ULTRA LORD VERO LAYOUT

2009-03-25T20:39:00.008-05:00

the ultra lord is a high gain fuzz that was created by andrew carrell and licensed to the Tone Factor brand. i haven't had a chance to build it yet, but apparently it sounds awesome. the origin of the circuit is originally based of a circuit called the dirty sanchez which carrell designed in order to have something that was a cool sounding, high gain fuzz, made from easily available radio shack parts. the ultra lord is a tweaked version of the dirty sanchez apparently taking it's sound to it's full potential. the UL looks to me like a bazz fuss running into a darlington pair with a mark hammer modded shin-ei fy-2 style mid scoop control on the end and a sag pot for the voltage. a combo of some nice snippets. here is vero layout that i made- it is unverified, but thoroughly checked. if you make it, let me know!
the schematic can be found HERE.
the thread for the ultra lord at freestompboxes.org can be found HERE.

DIRTY BOOTS GERMANIUM OVERDRIVE

2009-03-05T18:52:00.009-06:00

this little circuit is really what got me started in the whole DIY effects design process. i needed something that i could use to dirty up a loud, clean amp just enough to where it would have a touch of grit. it's a great little overdrive that can be used as a germanium booster as well as a fuzz if your pickups are hot enough.

it all started when i decided to breadboard the Trotsky Drive by Beavis Audio, which is basically a GE version of the Electra Distortion with a bias adjustment pot. using a russian GT313A transistor, i was fooling around with it, messing with values and such, when i remembered that the Bazz Fuss uses a diode in the C to B position instead of a resistor like the Trotsky/Electra. so i tried it out, and i got an excellently biased gain stage with just a bit of compression. then i realized that the circuit i was working on was PNP, where the BF is NPN. so the diode configuration is actually reversed. eventually i came to learn, with the help of many generous folks in the DIY community, that the GE diode that i was using was leaky, all of them are leaky, and it is this leakage that is actually acting as a large resistor and biasing the transistor. cool,huh? along with that, i'm sure that the diode is adding it's own little stamp on the situation with a bit of compression an break up.

after messing about with a ton of diodes this way and that, with filtering, in series, etc., i decided that i'm just not that big of a fan of diode clippers. i find them unnatural sounding, and their clipping just sound too "obvious" to me for some reason. so i ditched the clippers, added a small cap from C to B to roll off a bit of highs, and just put a whole nother stage in series with the first.

Lo! the Dirty Boots was born.

eventually i ended up trying a bias pot on the second stage and some different switching options for changing gain and tone, etc., but ended up with a normal emmitter controlled gain stage, a pregain control, and a volume pot. the latest mod was the series resistance between stages and ditching the cap from C to B on the second stage to open it up a bit.

it's really a great sounding little circuit using ge trannies which can be found on the bay for dirt cheap. the basic gain stage can be used for other things as well- it became the basis for The Toecutter.

give it a try sometime, or i'll send my band of mutated hobbit rat people to dig you out of your bomb shelter and eat you for second breakfast.

the thread at FSB about the Dirty Boots can be found HERE.

many thanks go out to Martin Chittum, Marcelo "Mac" Tripodi, and others that helped me understand along the way!

here is a layout using common sized parts. i have another for use with the extra mojo axial caps and such that i will post later.

daniel zink made this great version of the Dirty Boots in a Hammond 1590A box. a little killer!

here's another one from mr. zink- very stylish!

Apocalypse Audio- Thundertone

2009-02-16T19:55:00.011-06:00

here's something i churned out the other day. i have been thinking about modeling the Supro Thunderbolt with FETs, but then thought- i just got in these cool new Tesla GE's, why not use those? so that's what it is, the preamp section of the legendary amp used by Page and supposedly Hendrix, done up NPN germanium style. i had to eliminate a few resistors towards the end to bring up the volume and lowered the value of an emitter resistor to up the gain a bit. also, i made the resistor on the input variable so you can adjust the input impedance for guitars with different pickups.

the real gem of this circuit is the tone pot- totally counter-clockwise you get a nice full range tone with plenty of mids. as you go clockwise it goes to a very muffled tone, and as you go even further, it goes to a very thin, cutting tone. there are some very cool sweet spots, and a lot of versatility. i like it better than a regular muff style control, but it does cut plenty of signal- hence the two gain stages after it.

it's a cool sounding circuit. nicely voiced and does a good overdrive type sound. if you don't have the trannys, you could change out the 33K Rc's to trimmers and adjust to taste. the tesla trannies are extremely consistent, so no trimmers needed. the layout below uses some large axial caps and is yet unverified, but hopefully i'll get it done sometime soon.

XXXUPDATEXXX the large parts PCB is being retooled due to infestation of mutant roaches. stay tuned! XXXUPDATEXXX

XXXXUPDATEXXXX i was made aware that there could be DC voltage on the tone pot. you may need another capacitor after it to get rid of crackle that may be present. a .047uF cap off of lug 2 of the pot should remedy this. i'll amend the schem and layout after i do some more experimenting. XXXXUPDATEXXXX

XXXXXXXXXXXXXUPDATEXXXXXXXXXXXXXX I built up the Thundertone with the old mojo parts layout and it works with no tone crackle!I will be revamping it for a tighter layout. XXXXXXXXXXXXXUPDATEXXXXXXXXXXXXXX

take it easy!

here is a new PCB using common size/value parts.

La Revolution Deux

2009-02-15T19:10:00.002-06:00

mr. fred briggs, one of the main men over at freestompboxes.org, has a cool blog happening with lots of great layouts. it seems to be mainly centered around "bootweek" pcb layouts, effectively demystifying the mojo and bringing us all squarely down to earth. a truly commendable effort! there are also some of mr. briggs own diy designs, which i've heard have quite a bit of mojo(the good kind) themselves! check it out HERE.

e. euro effect projects

2009-02-09T14:46:00.006-06:00

HERE is my compilation of eastern european effect schematics. many of these designs are very interesting, my guess being because they were made in a sort of vacuum. fuzz faces and tonebenders were not around for cloning(actually that's not totally true, you'll find the occasional FFclone even behind the iron curtain), so they had to come up with designs of their own. included are some yugoslavian diy projects(THANKS BORISLAVGAJIC!), some very cool russian jfet designs by victor kempf, and even a couple east german production fuzzes. these are a great look at different ways of achieving interesting effects when copying previous designs wasn't an option, and some are straight up clones. check them out, there is some cool stuff!

The Toecutter- PCB layout

2009-02-09T02:41:00.003-06:00

i whipped up this layout in Eagle last night. hopefully i'll get to building it soon and get it verified. The Toecutter's sludge can't be stopped!

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LAYOUT IS VERIFIED.

HERE is a link to the Toecutter thread at FSB.org.

DEATH BY AUDIO- FUZZ WAR

2009-01-30T13:55:00.002-06:00

the dba fuzz war got re'd a ways back on freestomp, and some requested a vero layout for it. since i've been trying my hand at the strip layouts lately i thought i'd give it a shot. it's a pretty cool sounding fuzz from the clips that i've heard, extremely thick and nasty. the internal drive control was brought outboard for an extra control, and i added some power filtering as well as deleting some components that weren't being used. you can check out the thread on this unorthodox fuzz design HERE.

the main gain stages in the fuzz war use transistors that are reversed in orientation from the way they would normally be. by placing them backwards, you can take advantage of what is called the reverse beta of the transistor. this is basically how much gain a particular tranny has when it is reversed. check out more in jack orman's article HERE.

MASTERBLASTER

2009-01-28T03:31:00.011-06:00

WHO RUNS BARTER TOWN????

well here's my latest design. this one started out as my attempt at getting an AC30 type tone, but turned into much more. with it you are able to go from a cleanish boost to a light OD, to a fuzz, depending on how you set the controls and how hot your pickups are.

there are 2 gain controls built around a 3 tranny germanium platform using some low leakage soviet ge's with a gain range of around 40-60. the Blaster pot is the main Gain control and the Master control does more of a mid/hi boost in gain. the Blaster pot is set up a bit like the AC30, but there is also the HI/LO switch which basically allows you to go from something like the AC's Top Boost channel to the AC's Normal channel. in the HI position this thing does a great treble booster impersonation with a real glassy, sparkling, top end and can get up to a very tight focused fuzz sound. in the LO position the tone gets filled out a bit and you have another octave on the low end. turn up the Master and Blaster controls and you end up with something like an AC30 crossed with a germanium fuzz. finally there is the Gas control which is your basic voltage starve pot. i found that this thing can survive on extremely low voltage(i ended up using a 350K pot) as there is still plenty of boost to bring the volume up. with the Gas down, the tone gets thicker and crunchier. very cool with your tone rolled off on the guitar as well for a super nasty thick fingerpicking or slide blues fuzz. very lofi! there really are a lot of options with this thing- boost, OD, or fuzz, and it's got tons of hi-mids. it'll cut through a mix for damn sure. i might end up doing a high end roll off pot or switch at the end of the circuit as well, but that's kind of an afterthought.

i have a feeling that this is going to be my go to box for any type of garage/punk/blues kinda stuff. i haven't tried it out with my big amps yet, hopefully soon.

attached is the schematic and PCB layout(unverified- all my shit is packed for the move this weekend). also just so there is no confusion- the layout is made for some larger size components that i wanted to use. hopefully i'll get some sound samples done soon and post em up. thanks to SoulSonic for the help with the extra gain control, Bjorn Juhl, and the Vox AC30 for inspiration. cheers.

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just a little heads up. when i intially tested this circuit, i did so with my Airline T&C which has very low output pickups. with mid to high output pickups, it gets into a pretty blazing fuzz with the gain up. this could be tamed by simply putting some resistance in the circuit at the input with a pot. of course you would then be up to 3 gain controls, but hey, that's what this shit is all about right? but seriously, you could replace the Blaster pot with a fixed resistor and all would be well. another option would be to ditch the gas control, and add the pregain. this could be done by those more interested in traditional,"nice" tones.
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- THERE ARE A COUPLE OF ERRORS WITH THE LABELING OF THE POTS AND SWITCHES ON THE LAYOUT, THE GAS AND MASTER POTS SHOULD BE 3 AND 2 INSTEAD OF 1 AND 2. THE SWITCH SHOULD BE 1,3,2 INSTEAD OF 2,3,1 FROM LEFT TO RIGHT. I HAVE A BETTER LAYOUT THAT I WILL POST SOON AS WELL.

ONE MORE THING-
THE MASTER POT IS BETTER AT 25K RATHER THAN 50K.

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here is a smaller, tighter, layout, for use with normal sized components. unverified as of now, but eagle says it's good.

another cool mod is to replace the .0047 cap after the switch with a 470K/470pF combo in parallel. replace the .047uF cap with a .47. this makes the 2 channels very different- one lighter and a bit brighter, and the other thicker and heavier.

EFFECTOR13- SODA MEISER

2009-01-15T21:59:00.003-06:00

dammit- i had a whole article written and it accidentally got erased. fuck it. here's the SM schem and vero- verified. enjoy the squarewaves. click title for the full story. out.

folk fuzz vero

2009-01-14T19:11:00.003-06:00

i did up this vero layout today. Torchy had made one already which was just fine, but there were a few things i wanted to change, so i just made my own. mines a bit smaller, and the LED and other wiring is offboard- less connections, less wiring, less breaks AFAIC. this is supposed to be a great sounding design by Bjorn Juhl of BJF ELECTRONICS, AND MAD PROFESSOR. Bjorn's stuff is highly admired in the pedal industry, and he's a cool guy that contributes over at FREESTOMPBOX.ORG now and again. i'll probably breadboard this up soon, and then try out this vero layout. if anyone decides to tackle this thing themselves, let me know!