Adding a transistor stage to an effect

[Flynn]

Hi all,

I took this booster schematic from muzique.com and fooled around with adding a distortion circuit to it.  It sounds great to my ears, but there is a noticeable drop in level when engaged. 

I'm looking for some guidance on inserting a 2nd transistor to this distortion section to bring its level up using a pot.

Thanks for any input.

[Danich_ivanov]

Value of R6 is super small, i would replace it with 5-10k pot, and see what happens, should help with volume issues. Or just eliminate volume control and replace it with ehx lpb-1 (or something similar, could be SHO, any kind of boost circut), will be the same as adding a booster after it. But that R6 is definitely too damn small.

Also you can replace 100k pot with 500k.

[duck_arse]

in your A - B string, you have two caps. you only need one, the 1uF will swamp the 10uF value, so you might as well toss the 10uF. and why not add a second stage the same as the first [less the A - B string], taking the output of the first stage from the 100k pot as Q2 input? the second stage output vol pot could be replaced with a fixed 100k to ground, as a pull down.

[Ruptor]

You could put a 10uF cap across R6 to increase the gain but I think your feedback circuit is altering the gain when switched in.

[Flynn]

thanks for the input, fellas.

yeah, im not shooting for more gain on the clean-boost stage (it's already perfect).  Just looking for more gain on the feedback/diode side.

@duck_arse:  i borrowed the 10uf from another schemo, but as the note died out it started to do that squelchy dying-battery sound, but this little cap at the end fixed that.  i will try it without the 10uf!

[brianq]

So basically it's like  a Muffer with a switch on the diodes? Why don't you just put an lpb 1 behind it,change R6 390 for lpb-1,which is basically what your circuit is without diode/capacitor combo? Good luck.


Sent from my iPad using Tapatalk

[Flynn]

@brianq 
Yes, its the same sort of beast (clean boost) as the muffer.  I started with the muffer, then switched to this Muzique one and added the muffer's diode topology, but mixing things up a bit in terms of the diodes and cap. 

@duck_arse
Removed the 10uf cap, no difference, thank you!

@Danich_ivanov
Thanks, i will give that a shot.  regarding that collector/emitter resistors, the LPB1 actually has the same 10k/390 combo (though, admittedly i did change it down to 330).   I actually put in a 470 instead of the 330 - didn't like it, then put both the 330 and 470 in parallel and i like it so much i'm going to put it on a switch (between the 330 and the 180 ohms of the two in parallel!).     

i think the reason there are so many variations out there on this circuit is we all have or own variations as players!   :-)

i'm going to be fooling around with this thing over the weekend and will report back

[Flynn]

Wired it up and did a quick recording. 

I used a Strat copy; middle pickup setting; vol and tone knobs at full.   

Guitar goes into the effect, then to a single-ended tube amp.  Mic'd a few feet away with a large diaphragm condenser.

In the audio clip you will hear:

1)  Clean boost
2)  4 diodes and 1uf cap; 330ohm on emitter
3)  4 diodes and .01uf cap; 180 ohms on emitter
4)  6 diodes and .0047 cap; 180 ohms on emitter

https://soundcloud.com/user-342548702/boost-dist-demo