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.