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Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 2:41 am
by cprescott08
I just purchased a Crumar Performer that was supposed to be Fully Functional.
Unfortunately, that is not the case.

The String section is not producing any sound at the main output.

I do notice if a cable is plugged into the signal out that the string section crescendo and sustain sliders
are operational if that might help in the diagnosis.

Any insight would be appreciated.

Thanks!

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 3:03 am
by fh991586
Forgive me for asking such a stupid question, but is either 16' or 8' buttons pressed?

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 4:07 am
by cprescott08
Yes. I've attempted all the different combinations available in the string section.

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 5:47 am
by fh991586
Have you opened it to do a visual check, just in case there's something unplugged?

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 6:00 am
by cprescott08
Yes. Been in the game for sometime now and know how to at the very least check over the BASICS.
Comes with the territory when dealing in vintage gear. I've acquired enough knowledge and experience over the years to expect some issues and perform minor diagnostics and repair. Do you have any experience with the Performer?

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 4:40 pm
by rhino
If the seller is trustworthy - that is, if the synth WAS fully working but failed in shipment/transport - Check again for cracked PC boards, loose connectors etc.

Looking at the schematic, two failures could kill the strings, but let other features work:

IC2 - a 1458 dual op-amp

IC5 - a 741 op-amp

Both are located on the P-559 board

Scope or audio trace the input and output pins and see if they're both passing signal

EDIT: Never had one so going souly off the schematic: Can you switch the BRASS signal into the delay and verify the analog delay is not dead?

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 6:02 pm
by cprescott08
Well, I fired it up today and now nothing is working. The lights come on but, no sound output at any of the output jacks. I'm also noticing that the modulation rate led is solid red and is no longer blinking in time with the rate slider.

To answer you question previously I believe the brass was passing thru the delay as the crescendo slider in the string section was effecting the brass sound. Not sure if that's what you were asking though?

At this point I will probably just return it for a refund. I've already been in contact with the seller stating
the issues and fortunately they are agreeable.

Any suggestions on the current issue?

Thanks!

Re: Crumar Performer String Section not working

PostPosted: Thu Feb 20, 2014 8:54 pm
by rhino
Well, the fact that ANOTHER problem has suddenly cropped up is another (to me) sign of something loose.
Had my shre of Ensoniqs that looked spotless inside, but had that damned grey "mold" on the connectors. Just the weight of the cable moving can make/break the contact.

While you have it open, check the power supply if you have not yet done so.
There are 6 outputs
+24, -24, +12, -12, +9.1 and +6.2

Even integrated regulators can go wonky over time.

Re: Crumar Performer String Section not working

PostPosted: Fri Feb 21, 2014 5:30 pm
by fh991586
cprescott08 wrote:Yes. Been in the game for sometime now and know how to at the very least check over the BASICS.
Comes with the territory when dealing in vintage gear. I've acquired enough knowledge and experience over the years to expect some issues and perform minor diagnostics and repair.


I'm sorry, but I had no way to know your expertise on the subject! There's a lot of different types of members here...

Do you have any experience with the Performer?


I own one, and I've removed and cleaned every keys on it, while also fixing a almost broken key (viewtopic.php?f=5&t=62712). I'm afraid that's all I can be helpful about, so nothing considering your problems. Just trying to help... :|

Unless you really want that Performer, I'd deal with the seller to send it back for full refund.

Re: Crumar Performer String Section not working

PostPosted: Mon Aug 03, 2015 12:26 pm
by voxxline
I have the same problem. Did you fixe it?
:cry:

Re: Crumar Performer String Section not working

PostPosted: Tue Aug 04, 2015 5:58 pm
by sam
Start with the power supply
Then check the master osc with a signal tracer or scope.

I have fixed a few of these and all the problems were on the pot board...bad solder joints around the pots.

Re: Crumar Performer String Section not working

PostPosted: Tue Aug 04, 2015 7:08 pm
by Dr. Phibes
The trilogy I'm fixing at the moment (uses lots of the same circuits) had a few dead op-amps that caused similar problems.