Dodgy Roger 5

[Kipper4]

Hey guys
Just throwing this out here for some helpful soul to chip in with ideas on what could be done better.

I've been breadboarding this little sweller circuit for a few weeks but I've come to a crossroads where I can't seem to improve it. (improve it) shorter attack time. shorter release time.

If I make the recovery pot smaller i dont get enough compression to make it work as intended.

Heres a link to the thread that gave me the idea to persue this
http://www.diystompboxes.com/smfforum/index.php?topic=116164.msg1074641#msg1074641

I'm in a bit of a breadboard hole.
Thanks
Rich

schematic

[Fender3D]

What if you raise C8? Or decouple it from the zener? (maybe just a resistor...)

I'm in a bit of a breadboard hole.

Did you follow the breadboard rabbit?...

[Kipper4]

"Did you follow the breadboard rabbit?..."

Big ears?
White top hat?
Big eyes?

That's the fella. Did you follow him too?   

It's just a new approach for me to investigate.
Not opto.
And some different rectifiers.

[rankot]

Looks interesting!

[TejfolvonDanone]

Might be a long shot but the Q2 stage has a much higher collector resistance than on my design and it also feeds two lower value resistors. So you have a gain stage with about 35k output impedance which feeds a 33k resistor on the positive going signal and minimum 15k maximum 23k resistor otherwise. So there is a large drop between the two. I think that is the reason that if you decrease the recovery pot you get less compression.
My guess: get rid of the compression knob and put a fix resistor there. Put an NPN transistor's base (let's call it Q5) to the collector of Q2, Q5's collector to the 9V rail and its emitter through a pot (1k to 5k would be my guesstimation) to ground. That way you get a DC coupled emitter follower with variable output voltage. If this helps the case I think a dual op-amp would be better instead of Q1,Q2 and Q5.

R11 could be higher (1M like on my design) as it is there to prevent any leakage build-up.

some different rectifiers

D1,R12, the recovery pot and C8 forms a negative half-wave rectifier. It's the same as most rectifiers but it gives a negative voltage. Q2 gives additional gain so there is enough control voltage to the upper JFET's gate.

[Kipper4]

Thanks I'll get back to it soon.
Rich