OBERHEIM SYNTH group photo

Yahoo Groups archive

OBERHEIM SYNTH

Index last updated: 2026-04-28 23:39 UTC

Thread

Matrix 1000 uneven volume upper octave

Matrix 1000 uneven volume upper octave

2015-11-05 by sanchez.demian@...

Hi everybody.

I have been struggling with a matrix 1000 for a while.

Basically I replaced the battery and loaded the factory patches but when I play it, I can hear on all the patches that at a certain keyboard point, the volume of the patch jumps drastically.

It is not always on the same key, but it is always on the upper octave.

I tried to run the calibration, but it stays there forever, which makes me think there must be some issue with the CEM or maybe some of them do not make good contact.

Voice test shows all the voices play and the high volume issue affects all the voices equally.

Anybody experienced this?

Thanks

Re: [oberheim] Matrix 1000 uneven volume upper octave

2015-11-05 by Boniforti Flavio

If you find out that some CEM has been gone - I'd have a couple spare.
F.
Show quoted textHide quoted text
sanchez.demian@gmail.com [oberheim] <oberheim@yahoogroups.com> schrieb am Do., 5. Nov. 2015 um 12:08 Uhr:

Hi everybody.

I have been struggling with a matrix 1000 for a while.

Basically I replaced the battery and loaded the factory patches but when I play it, I can hear on all the patches that at a certain keyboard point, the volume of the patch jumps drastically.

It is not always on the same key, but it is always on the upper octave.

I tried to run the calibration, but it stays there forever, which makes me think there must be some issue with the CEM or maybe some of them do not make good contact.

Voice test shows all the voices play and the high volume issue affects all the voices equally.

Anybody experienced this?

Thanks

Re: [oberheim] Matrix 1000 uneven volume upper octave

2015-11-05 by Demian

Thanks Flavio, it is good to know
So I “think” I fixed it..
Removed voice 3 and soldered a new dock for it.
Removed cleaned and reinserted all IC that were not soldered directly to the main board
Zeroed the DAC.
Initialized and reloaded the factory patches.
So far so good….
Show quoted textHide quoted text
From:  <oberheim@yahoogroups.com> on behalf of "Boniforti Flavio boniforti.f@... [oberheim]"
Reply-To:  <oberheim@yahoogroups.com>
Date:  Thursday, November 5, 2015 at 3:41 PM
To:  <oberheim@yahoogroups.com>
Subject:  Re: [oberheim] Matrix 1000 uneven volume upper octave

 
 
 
 
   

If you find out that some CEM has been gone - I'd have a couple spare.
F.

sanchez.demian@... [oberheim] <oberheim@yahoogroups.com> schrieb am Do., 5. Nov. 2015 um 12:08 Uhr:
 
 
 
 
   

Hi everybody.

I have been struggling with a matrix 1000 for a while.

Basically I replaced the battery and loaded the factory patches but when I play it, I can hear on all the patches that at a certain keyboard point, the volume of the patch jumps drastically.

It is not always on the same key, but it is always on the upper octave.

I tried to run the calibration, but it stays there forever, which makes me think there must be some issue with the CEM or maybe some of them do not make good contact.

Voice test shows all the voices play and the high volume issue affects all the voices equally.

Anybody experienced this?

Thanks

Re: [oberheim] Re: Matrix 1000 uneven volume upper octave

2015-11-05 by Demian

You mean UC711?
Show quoted textHide quoted text
From:  <oberheim@yahoogroups.com> on behalf of "rajahpatel@... [oberheim]"
Reply-To:  <oberheim@yahoogroups.com>
Date:  Thursday, November 5, 2015 at 3:55 PM
To:  <oberheim@yahoogroups.com>
Subject:  [oberheim] Re: Matrix 1000 uneven volume upper octave

 
 
 
 
   

probably a multiplexer.  the one off the DAC that goes the 6 voice chips each associated with 2 further multiplexors.

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.