Those with GREAT knowledge of 3080 style comps.

[9Lives]

I just finished buildng the Sabrotone vero version of the "Jangle Box" it's very dynacompish with some subtle differences. This is my first time using the strip board. It's very useful stuff. I highly recommend it for personal stuff. The problem I ALWAYs run into with these ota compressors is that I get to much distortion. Before anyone jumps down my throat, I understand comps produce noise and yada yada.. I've built several.i just want to know if anyone has a lead on some info about any modifications I can make for my active humbuckers. I can get them pretty clean with hot passive buckers but the actives are just to hot! The only way I can clean it up is to roll back the vol on the guitar and compensate with the boosters after the comps.. What causes this? I can't figure out what part of the circuit that effects this. Impedance maybe? I don't think so. I'm wondering if the ca3080 just can't  amplify that hot of a signal without some clipping somewhere. Am I on the right page, or totally off? The comps I've build with the lm13600 don't dlip near as bad but I just want to understand this. If there was a way to weaken the signal before it hit the amp I think that might be the key but I'm still pretty amateur. Thanks for reading my rambling thought process. Anyone who knows about this I'd greatly appreciate. Thanks.

[stecykmi]

disclaimer: I don't know the 3080 that well and i'm not that familiar with any 3080 comp builds. however...

I believe OTA's are sensitive to large input signals (I have no idea how to use them, but the LM13600/700 have linearizing diodes to help with this. Most of the time they are left disconnected, however).

My initial thought is to create a little "pad" switch that attenuates the input signal, then make up the gain at the end.

[Scruffie]

It's a near enough 40 year old design using a chip designed at the same time, it wasn't designed with active humbuckers in mind so I think you'd be better off just using a different compressor when you want to use active pickups than trying to fix it.

It is because the 3080 is in the Audio Path, the MXR Sustainer uses a different approach that shouldn't clip but i'd just look to other styles of compressor.

[midwayfair]

I can't claim any deep knowledge, but I've got one next in line to be soldered, which means I'm going to be doing a bunch of research into understanding what each component does. If I find anything that might be of use, I'll let you know.

In the meantime, I can say that the Ross/Dynacomp is a limiter circuit. Your active pickups might be bumping up against the volume limiting and distorting - this happens in studio compressors (even digitized plugin ones!) when the limit is set too low. It creates this weird sort of square wave sound.

If it's a headroom problem - have you tried building a version that runs on 18V? They exist (Keely, right?)

There's an attack mod (a pretty well known one) that might help a little; stecykmi's suggestion of making up on lost gain elsewhere in the circuit might work, but that involves replacing your pickup's character with that of the compressor, and would destroy the fairly transparent nature of the compressor. My gut tells me that you're not going to like the easiest way to squelch the distortion, which is to heavily load down your pickups in the front end and then ... make up for the lost gain with boosters ...

[midwayfair]

Sorry for the double post, but I think I found a solution for you. AnalogMan (who I imagine has some pretty decent knowledge of the Ross circuit!) specifically mentioned active pickups in the "higher voltage" section of his page on the comprosser and sez anything up to 15v is safe and will work better with super high output pickups. Sounds like a road rage might be the ticket!

http://www.analogman.com/rossmod.htm

[9Lives]

I forgot about this post lol.. I I figured some of those reasons were probably why.. Never hurts to ask. I just build sabro (however it's spelled) flatline comp.. Allows a little more slam, but I havnt got it sounding to great with hi gain pedals following it. I also jerry rigged the optocomp with some crap I got from radio shack. I searched the net for the best led/ldr combo and that seems "the big mystery" at first I used the bigger one and a clear yellow led. It was decent but  OF COARSE I have to tamper and screw around with everyrhing.. I mean what kind of diy-er would I be if I didn't?? I started testing values in the light and in the dark and most reached close to 20k in the dark and varied from 3k-5k in the light. Keep in mind this is the 5 pack from r-shack. I chose the one with the largest range from my amateur tests and got one 4k to 20k and used the brightest clear RED led I could find. This made it more "transperant" so they say. I don't thin any comp is transparent.. Just my opinion. I don't really want a "transperant" comp.. I'd just turn it of hehehe. I'm still VERY interested with the whole octocoupler deal. Very very fasinatingly simply effective. I just hate using sockets. I havnt found a good way to solder single sockets. I can barely break the damn things off right. Also a quick question for anyone reading this, my flatline is a bit noisey at high sustain setting. It's like a pulsating sound. Only with dr boogie on after it. Is this my choice in ldr/led? I also rigged in a small indicator led spawning off the same amp receiving the light w the ldr. I used a 100uf elc cap and npn tranny to ground. It works... Kinda. Not sure I did it right,  but I damn sure aint gonna mess w it anymore. It's good enough for my first ldr build. I think I'm goin for the philosopher's tone next. But back to the original subject the janglebox is pretty nice. If you like that over the top treble sparkle this thing definitely delivers. Sorry for the poor spelling and grammar. I'm on my cell.

[midwayfair]

I havnt found a good way to solder single sockets. I can barely break the damn things off right.

You might try this instead: Get a bunch of 6-pin sockets (they're like 2c from Tayda) and cut them down the middle. The pins on the bottom are easier to bend than the in-line sockets. They'll rock a little but they won't go anywhere. I used to do this all the time until I figured out that bending the in-line sockets like this:

< ^ >

with a small screwdriver kept them in place perfectly.