Tonepad Ross compressor debug

[jakenold]

I believe the problem you are having it due to the fact, that we got no review of the Timmons concert!! 

That man plays an amazing guitar.

mfg Jake

[Plinky]

Sorry guys... for some reason I stopped getting emails about replies to this thread.

So I'm not the only one with this problem, eh?? I just made an order from Small Bear. Maybe I can get a couple of CA3080s from him and see if it is in fact a bad batch of ICs from FX conn. Maybe Jake and me should both contact FX Conn with our dilemma?

Looking at your test schematic oskar, I noticed that the IC power & ground pins are reversed. In the 3080 datasheet and on the tonepad layout, pin 4 is V- and 7 is V+. Any particular reason for this???

BTW, Timmons put on another good show as usual. Since he signed on with Favored Nations he doesn't play around Dallas much anymore and it's harder to get a moment to talk with him like in the past. He was surrounded on all sides by fans so I didn't get to say hi to him after the show. Although, he still reads all the email from his site and I did get to chat with him briefly before the soundcheck. Truly one of the most humble and nicest guys I've had the pleasure of meeting.

[oskar]

I fired off a mail to fxconnection just in case but they didn't answer...

Looking at your test schematic oskar, I noticed that the IC power & ground pins are reversed. In the 3080 datasheet and on the tonepad layout, pin 4 is V- and 7 is V+. Any particular reason for this???

Because I'm just that stupid...

So I'm not the only one with this problem, eh?? I just made an order from Small Bear. Maybe I can get a couple of CA3080s from him and see if it is in fact a bad batch of ICs from FX conn. Maybe Jake and me should both contact FX Conn with our dilemma?

I still don't think it's a bad batch, but you can't rule it out... I've seen bad batches of components before (maxim rs232), things started to freak out at work
and eventually they sent failing components to a lab that cracked them open and just put them under a microscope. You could really see strange oxidpatches and scratches on the photos. Still it's highly unusual.

BTW, Timmons put on another good show as usual. Since he signed on with Favored Nations he doesn't play around Dallas much anymore and it's harder to get a moment to talk with him like in the past. He was surrounded on all sides by fans so I didn't get to say hi to him after the show. Although, he still reads all the email from his site and I did get to chat with him briefly before the soundcheck. Truly one of the most humble and nicest guys I've had the pleasure of meeting.

Timmons... who?   

ps. check out my uberamazing schemo in the FX-X voting thread!!!

skar

[Plinky]

www.andytimmons.com

Great guitar player. I have both of his Ibanez signature models - the AT100 and AT300.

Not sure how long it will take FX Conn to reply since he's in the process of moving to North Carolina. The site said approx. 3 weeks. 

I went ahead and ordered a couple of 3080s from Steve at Small Bear. That should determine if the chips are ok or my construction skills are lousy.

[oskar]

Ok. Long thread... double_check resistance pin5 to V+...
otherwise...   It should work!?

?

[Plinky]

Wasn't sure where again, so I made a couple of measurements.

Pin 5 to Pin 7(V+) - 600 megohm
Pin 5 to 9v input on pcb - 600 megohm

[Plinky]

DUDE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

     It's the chip!!. I just got my order from Small Bear. Steve's 3080s are different than what I got from FXConn (RCA instead of Harris/Intersil). All the voltages at the IC are perfect - 4.85v on pins 2 & 3, .6v on pin 5. I'm posting this just as I took the readings. Will post later with sound results.

[Plinky]

I don't use a compressor regularly, so I'm not sure if it's working or not. I notice a level change, but that's it at the moment. I wish this would've happened sooner. I have to get ready for a gig, so I have to wait until I recover tomorrow to play with this.

[oskar]

DUDE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

     It's the chip!!. I just got my order from Small Bear. Steve's 3080s are different than what I got from FXConn (RCA instead of Harris/Intersil). All the voltages at the IC are perfect - 4.85v on pins 2 & 3, .6v on pin 5. I'm posting this just as I took the readings. Will post later with sound results.

I can sleep again...   
Same source though I think... RCA (marked CA) where bought by Harris who where bought by Intersil...? ...something like that...

[Jackie Treehorn]

Yes, it is the chip.  I picked up a couple NTE996's yesterday (which are relabeled LM3080's, actually) and got my dynacomp working.

I've been tweaking it and haven't had time to post!  The stock circuit didn't sound that great, kind of harsh, noisy, and distorted, so I've been doing Ross/Saffron Squeeze type mods and swapping the ceramic/electrolytic coupling caps with film caps.  Putting the 10k on the collector of Q1 with 33 mf of filtering was the push over the edge!  Quiet and more lush!

[Plinky]

From what I can tell it's working (see earlier post concerning performance )

My big problem is at the moment I don't have a real good clean amp to really test it out. I sold my Deluxe Reverb reissue, my sister's boyfriend has my Blues Jr., and
I don't feel like unloading my Stiletto from the truck (very nice clean for a 2 channel high gain amp). Having said all that, all I have at the moment is a Torres overhauled silverface Champ (I installed kit #3 - the whole shibang ).  It's got a great clean sound, but it starts to break up at about 5 so it's really hard to tell without a lot of on/off comparison.

The pedal is very quiet for one that is not enclosed. I built the Ross version, so I have the cap/resistor combo you spoke of and more. : D I have a gig coming this Saturday, so hopefully I can get it enclosed and test it out at full stage volume. I still have the first pcb I did that I thought was faulty. I may just try that one - it's populated with tantalum caps instead of electrolytics.

[Plinky]

BTW, Thank you for all your help with this project Oskar. I greatly appreciate it.

[oskar]

You're welcome... 
I'm glad I stuck with it, even though I didn't feel good at all about seeing this thread bump right up again.
I'm still curious about what precisely is the matter with them chips ( knowing you they're all thrown away by now...? ).

oskar

[Plinky]

You're welcome...  Smiley
I'm glad I stuck with it, even though I didn't feel good at all about seeing this thread bump right up again.
I'm still curious about what precisely is the matter with them chips ( knowing you they're all thrown away by now...? ).

oskar

What's wrong with the thread continuing for so long? I've seen plenty of threads here way longer than this one.

I haven't thrown them away. I sent an email to John at FXConn to see about getting a refund or some known good replacements.

[Jackie Treehorn]

Now the 4 Intersil chips I ordered from Small Bear arrived.  Interestingly enough, they sound somewhat different than the LM3080.  They get more squeeze/squish and sound bolder, whereas the LM3080 is a bit more subtle.  There were also differences in the attack time of the Intersil chips.  I found one that had a bit slower attack which let the transient come through pretty well; lots of slam before the squeeze.  There was another that just got the click, which I didn't like much.  Then some were fast with the compression coming on immediately.

I'm really liking the pedal now.  It's got a great Little Feat type sound!