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Tuning issue: Pitch jumping around on single notes

Tuning issue: Pitch jumping around on single notes
« on: November 22, 2017, 09:25:56 AM »
This has happened a few times but usually goes away after a calibration or 2. But its just come back and it won't go away.

The pitch jumps up and down a few semitones every key i trigger. even if i trigger one note it will just jump up and down.

100% isn't the lao or anything like that.

Please help if you can! Very frustrating

Re: Tuning issue: Pitch jumping around on single notes
« Reply #1 on: November 22, 2017, 10:20:26 AM »
If you hold Manual and press button 3 it will completely erase the calibration table.  I was having similar tuning issues with my OB-6 despite many calibrations, and doing the above fixed it for me. 

Obviously after you reset the calibration table you will need to redo all the calibrations.  But for me it fixed the weird tuning issues I was having in the end.

Re: Tuning issue: Pitch jumping around on single notes
« Reply #2 on: November 23, 2017, 02:55:46 AM »
If you hold Manual and press button 3 it will completely erase the calibration table.  I was having similar tuning issues with my OB-6 despite many calibrations, and doing the above fixed it for me. 

Obviously after you reset the calibration table you will need to redo all the calibrations.  But for me it fixed the weird tuning issues I was having in the end.

Thanks man, thats seemed to of worked.

Re: Tuning issue: Pitch jumping around on single notes
« Reply #3 on: December 02, 2017, 11:57:23 AM »
After several months of use, my OB6 will still need the occasional call to the auto-tune routine from time to time, because it will drift slightly out of tune. Even after clearing the temperature table and painstakingly refilling it with new values over several weeks of use.
Much like the Prophet 5, which required the occasional "Tune" also, but much less severe than on a Memorymoog. ;-)
It's the nature of an analog beast I guess.
I don't believe in the claims made by several DSI service reps (contacted over the months on the issue) about the synth being in tune from power-on to hours on end. I've yet to experience that reliably on my OB6 (module version). It's not preventing me from enjoying the synth though, as the immediate fix is easy enough (pressing "Manual" and "0" buttons) and doesn't take much time. But then again I don't do live shows where a synth that slowly goes sharp by half a semitone would be a little embarrassing...

Re: Tuning issue: Pitch jumping around on single notes
« Reply #4 on: December 04, 2017, 01:54:27 PM »
As you know, there are a total of 48 slots for the temperature calibration tables. It is possible to fill the tables with overlapping data (which can be overwritten), and likely that you don't have 48 discrete temperature values stored. We haven't received any feedback to date that the tuning calibration has been an issue for live performance, nor any feedback additional feedback that the OB-6 won't stay in tune.

Your best bet is to simply keep calibrating as necessary and eventually you'll get to a point where you should rarely have to do it again. If the synth moves to a different location or there is an unusually hot/cold day you may have to tune again, but it shouldn't be a regular occurrence after the initial period.
Dave Smith Instruments

Re: Tuning issue: Pitch jumping around on single notes
« Reply #5 on: December 04, 2017, 03:41:36 PM »
Do we gain anything by trying to hit the extremes on purpose ahead of time (before going live)?  For instance letting the OB sit out on a cool night for a bit then running the calibration. Or after putting it in the sun (safely) to get it a bit warmer than normal.  Will that help keep things in check, or is it just a waste of time?

Re: Tuning issue: Pitch jumping around on single notes
« Reply #6 on: December 04, 2017, 03:48:55 PM »
It's all based on the temperature where you're performing. The OB-6 tuning will start to drift when the internal temperature rises (or falls) one degree Celsius from the last saved value in the table, or closest saved value, if the tables aren't full. So yes, tuning in a bit warmer conditions will result in those temperature values being stored ahead of time. I know it's hard to anticipate the temperature on the day of the gig, but the more varied conditions you tune the OB-6 under the wider range you'll be ready for.
Dave Smith Instruments

Re: Tuning issue: Pitch jumping around on single notes
« Reply #7 on: December 04, 2017, 09:21:03 PM »
Great, thanks for that clarification.