Polyphony problem, notes failing to trigger

Polyphony problem, notes failing to trigger
« on: January 13, 2019, 05:12:24 PM »
I've been experiencing this problem with certain patches (though never the basic patch) where every 3rd or 4th voice wont trigger. Even when playing chords it will omit a voice or two. The same patch will work perfectly well with unison engaged. I've racked my brain trying to figure out and troubleshoot why this would be happening, stripping away elements of the patch one by one to no avail. I'm including a dropbox link to a short video example of this behavior (pardon the sound quality).

Anybody experience something similar? I've already had an issue with a bad potentiometer on the right board of this unit and have an open ticket where I'm having to replace it. At this point I'm wondering if maybe I just got a lemon of unit?

https://www.dropbox.com/s/imvf0e7g8wjsuit/MVI_3599.MP4?dl=0

Re: Polyphony problem, notes failing to trigger
« Reply #1 on: January 13, 2019, 06:43:05 PM »
Have you tried a recalibration ? (Manual+0) ?
Oberheim OB-X8, Minimoog D (vintage), OB6 (Desktop), Oberheim Matrix-6 (MIDI Controller for OB6), VC340

Re: Polyphony problem, notes failing to trigger
« Reply #2 on: January 13, 2019, 08:14:39 PM »
Yes, every time I turn it on I usually tend to have to do at least one calibration. Still building the calibration table I guess (even though it's been 2 months), hence my desire to check the temps; I'm trying to discern whether it's going out of tune at new temps during the warm up process or whether one of the cards is actually unstable despite calibration data. Usually after one calibration the synth stays in tune as long as I have it on so I'm not terribly concerned there (even though 2 months seems a bit long), but unfortunately this has no effect on the polyphony issue.
« Last Edit: January 13, 2019, 08:18:14 PM by Joontree »

Re: Polyphony problem, notes failing to trigger
« Reply #3 on: January 13, 2019, 08:25:40 PM »
My next advice would be to get in touch with Sequential Support team via e-mail, or phone, and tell them about the polyphony problem. They might have some insight on troubleshooting the issue. I know that there are LED lights next to each voice card on the main board inside, to show which one is being triggered. There might also be a way to display which voice cards are being discarded by the MPU when they fail ? (some other secret diagnostic button combinations perhaps ?)
 
Oberheim OB-X8, Minimoog D (vintage), OB6 (Desktop), Oberheim Matrix-6 (MIDI Controller for OB6), VC340

Jdoo

Re: Polyphony problem, notes failing to trigger
« Reply #4 on: January 14, 2019, 12:45:54 PM »
If you are engaging a sustain pedal --- and the patch is not set to a ReTrigger mode ... the notes won't release, and you won't hear new ones being played.