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!!
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