E EURO TRANSISTOR INFO

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.

a comment from a Russian friend.

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

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!

DIRTY BOOTS SOUND CLIP

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

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.

TOECUTTER V.1 REV.C PCB LAYOUT

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!

AWESOME RUSSIAN GEAR SITE!

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.

DIRTY BOOTS TWEAKS

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.

SOME COOL PARTS SOURCING SITES

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.

ELEKTRATONE'S DIRTY BOOTS

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!

APOCALYPSE AUDIO - PANZER FUZZ

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!

DIRTY BOOTS GERMANIUM OVERDRIVE

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!