Very simple 20:1 compressor (sustain circuit) - no optics..

floris · Post by **floris** » 17 Jan 2009, 13:48

Yes, sorry, it was a poor attempt of me at a "wink" joke.
I agree that the lack of clear input and output indications makes the schematic unclear. Especially the output took me time to figure out.
The input is where V3 (input signal source) meets C1.
But still, looks like a nice idea of implementing compression. Anybody else tried it yet?

DrVilches · Post by **DrVilches** » 27 Jan 2009, 12:41

IN and OUT are both tags used in PSPICE for the purpose of monitoring voltages.. IN marks the point at which the signal is injected to the active part of the circuit (the circuit that comes before it, to the left, is simply a signal buffer) and OUT marks the point (wait for it...) where the output is taken from! I know.. scary stuff..

mikebike · Post by **mikebike** » 07 Feb 2009, 23:05

finally got around to bread boarding this.

can i use polarized caps for c2, c4 and c5? if yes how should they be oriented?

floris · Post by **floris** » 08 Feb 2009, 01:09

how should they be oriented?

In: https://www.freestompboxes.org/download/ ... &mode=view
C2 and C5: + on the left side.
C4: + on the top side.

mikebike · Post by **mikebike** » 08 Feb 2009, 03:14

hrmm. that how i got em.......

im not getting any sound out of it.

but i subbed a bunch of values

MrSparkle666 · Post by **MrSparkle666** » 03 May 2009, 07:06

So has anyone actually built this and got it working? How does it sound?

~arph · Post by **~arph** » 03 May 2009, 09:51

I tried it, but I couldn't get it to work. I did not have the BC337 so I abandoned it. I might try it again.

cspar · Post by **cspar** » 10 Jul 2021, 22:37

This is a fun little circuit to mess around with on a breadboard.

Is C3 in the correct orientation for the intended compression from Q3?

In my ears, I got more compression with the + facing the 2n2222.

Manfred · Post by **Manfred** » 11 Jul 2021, 00:01

Is C3 in the correct orientation for the intended compression from Q3?

Yes, C3 is in the correct orientation.

In my ears, I got more compression with the + facing the 2n2222.

This cannot really be, because the negative of C3 and the emitter of Q3 are connected to ground according to the schematic.
Is the wiring correct?

cspar · Post by **cspar** » 11 Jul 2021, 00:14

They were but I ended up both lifting the ground and flipping the capacitor.

I also ended up with a bunch more parts on the breadboard and it was halfway to a Jen HF Modulator.

I didn't have the BC337A so I subbed it. I have one on the way now though.

cspar · Post by **cspar** » 11 Jul 2021, 00:23

I guess I just wasn't happy with the lack of compression without the BC337a so I found it another way.

My real point is that the circuit is a interesting jumping off point for coming up with something that isn't YAFF or an Elektra mod.

And I wanted to make the schematic a little more understandable.