Breadboard fuzz noob question

[Dev...in]

Is there any precident or particular purpose for using two transistors in (series?) like E,B,C ---> E,B,C

Im screwing around with a very simple 2 transistor fuzz circuit and I have found placing a (third) transistor in the direct path of another transistor with correct orientation will either change the sound slightly or not at all. I realize you may need more information on the circuit to determine that im not a complete psychopath. For reference Im using the schematic for a Devi ever Silver crank.

Any input at this stage of maximum noobness is helpful. TIA.

[selfdestroyer]

This may help with some of your questions.

http://buildapedal.com/

I wish I would have stumbled to this website when I first started. It really helped me connect the dots on what I was learning. You might find it useful.

[Dev...in]

thanks that looks really good. I appreciate it.

[Bellyheart]

Sweet link.

[eatyourguitar]

do you mean piggy backing transistors? devi does that a lot.

[Dev...in]

Yep, that's what I'm doing... any advice for increasing output volume?

[eatyourguitar]

post a link to the schematic your using

[Dev...in]

Im using some amalgimation of this one: http://www.deviever.com/fx/oldforum/vie ... 192&t=8220

But the main one i was using seems to be missing from the google now. It had a volume controll on it. Im making the "gate" resistor a single 10M on a switch. Im also using different transistors. 9v goes to a 5k resistor before it hits Q1. Its basically two caps and two transistors at this point. Not very helpful i know,... I will try to make a drawing of what im up to but will probably just post a pic. Im happy with the tones im getting i just want a little "more". I like keeping it simple. Thanks for the replies.

[eatyourguitar]

\
I drew a schematic since I could not find one. this should make it easier to talk about and look at it. clearly the transistors are piggybacked. I'm not sure where your putting that 10M. my guess is that your probably limiting current somewhere with that 10M to get the gate affect. so if you want it louder without adding more transistors, you can't. I could build a two transistor gated fuzz with really loud output but it would not be anything like this schematic.

[Dev...in]

yeah i think (I'm at work so cant check) the 10m is right where you have R2. My original plan was to make make my own "andrew's pot" (a pedal with 2 "heroin lifestyles" aka silver cranks with sozo caps) I am using the sozo caps... lol, so expensive... but I have deviated from that plan. The actual output and performance of a single "heroine lifestyle" was sort of a let down. The original design is very quiet, you basically have to max the volume and gain in order to get anything useful out of it with vintage output pickups. It is a cool sound but really limited. The stock gate is really too heavy. With the gain under 1/2 you get no sound from the pedal.

[eatyourguitar]

bad news, those expensive caps wont make a devi pedal sound better. good news, they can't possibly make it sound worse. at 10m you are really chocking the shit out of this circuit.

[Dev...in]

yeah, I'm gonna put the resistor on a spdt. It isn't nearly as badly mangled as the real version and does reduce some noise. Increasing the resistance on R2 actually seems to get things more normal until a certain point, like 15m. Of course a number of things are different now. She has a 3.3m and a 2.2m. My 9+ goes to a 5k before the transistor and the only other resistor i poke in and out of is the 10m. Some sort of voltage division property im not understanding is at play maybe? She uses a 2n2907 and a MPSA18. I couldn't find these on Newark so I got some BC517G and MPSA13. Its been awhile since i was working from the original circuit but i was able to replicate it pretty close early on. As soon as i pulled out that 3.3 i liked the sound much better. I took out the MPSA13 and I have been loving the BC517G and a metal case motorola 2N026...

I will put some pics of my breadboard creature up here tonight. Thanks for the help eatyourguitar. I know i must look like a kid jumping in puddles to more experienced players. I have a 2 knob setup with a basic "gain" and volume. I need to narrow down a good pot value for gain. The 100k made squeals on the full and off positions till i fixed it with resistors.

[eatyourguitar]

have you thought about just adding another transistor before the output for makeup gain? also, how about disconnecting the collectors and finding the proper R2 for each one to get the gate. maybe one of them will gate nicely at 8M while the other is as 12M. then you just run them like that. it is one more resistor but it wont change the sound or deviate from the original design too much. MPSA13 is not too different from MPSA14, 18 etc... they are just really high gain silicon darlington transistors. Hfe800 to Hfe1400. 2N2907 is high gain but not as much as an MPSA18. 2N2907 is not a darlington. my whole thing about why I would use a 2N2907 is they just sound different than anything else.


here is how I do gated fuzz. put a voltage divider on the base that is less than 0.7v. any silicon transistor needs at least 0.7v at the base when the emitter is at 0v to pass a signal. if your voltage divider is 0.7 you get half wave rectification. but if it is at 0.4v you get a gate with half wave rectification and more of a square wave. basically you get more gate and more fuzz. check this thing I did a long time ago

[Dev...in]

That is a cool looking build. I will have to give it a try once my little project gets boxed up. I spent the day working on my drawing skills. I think this may be better than some disorienting pic of my messy radioshack breadboard. I'm really liking the sounds i can get out of this design. Its a very satisfying overdrive/fuzz hybrid. I didn't include the 10m in this drawing. Let me know what you think. I am still tweaking, but this is the heart of what i want. I have noticed if i lower the incoming 9+ voltage very slightly using a 10k pot i get more gain but then my range of broken and bizarre sounds increases exponentially and the gain knob stops acting nice. Ideally i would like to get more "normal" gain and volume out of what i have now. Thanks.

[eatyourguitar]

I have noticed if i lower the incoming 9+ voltage very slightly using a 10k pot...[/img]

are you lowering current or voltage? is it a voltage divider or a two wire pot in series to +9v?