How to get more compression in a distortion design

[TimWaldvogel]

Why can I do to add Ore compression to a distortion design

[TimWaldvogel]

I read somewhere that the expandora distortion uses a photocell diode to compress the signal a bit. Idk how though

[petemoore]

  Check out the DOD250, photoresistor compressor.
  basically the guitar lights an LED, LED lights the LDR, LDR is placed to set gain of the circuit, when lit [higher input lights it more] the LDR reduces the gain.
  Simple and effective as long as a slight lag in compression time is acceptable, which for a distorter I find useful [attack gets through, note stays loud because there's enough to keep the distorter pushing to compress, then when signal drops, LDR goes darker/gain goes up and can = nice sustainey distortion.
  Distortions compress [take DIST+ diodes to ground, nothing over X voltage gets past them], and distortion harder as well as compress harder when pushed harder [hotter pickups or booster in front].
  Depends on what you want, whether you like this or that series of effects, some say a compressor can be made to 'breathe' where a boost will put more constant pressure...depends on the distorter, the boost, the compressor and etcetera.

[TimWaldvogel]

Did you mean dod 250? I tried to search for a circuit mod with an example but I could not find anything

[TimWaldvogel]

And is there any other way to get a nice smooth not overbearing compression from traditional op amp distortion designs?

[brett]

Hi
just plug the signal into a CMOS inverter stage, such as the CD4069UBE, and apply 100% feedback (ie connect output with input).
There's six stages in a 4066, so you could try more stages, but I've never used more than 1.
cheers
PS although it might seem at first that nothing will happen with this unusual setup (wouldn't electrons travel around the CMOS device?).  But it only takes a few electron to join the exiting crowd and leave the gate for an N-channel CMOS to turn on.  Vice versa for P channel. And CMOS gates are insulated with glass, so the electrons are flowing in and out of a short dead-ends.

[TimWaldvogel]

Where can I learn more about CMOS inverters and CMOS ics?

[frank_p]

You could also check out Joe Davisson discrete opamp that some had used with the Rat.  I remember Aron saying it was worth it.

http://www.diystompboxes.com/analogalchemy/sch/diodeopamp.html

[anchovie]

Did you mean dod 250?

I think he means the DOD 280.

[Mark Hammer]

The simplest way is to just clip twice.  The Big Muff has two cascaded clipping stages and has one of the mst compressed sounds around.