Prophet 10 loosing tune after a few minutes

Micky

Prophet 10 loosing tune after a few minutes
« on: April 09, 2023, 08:27:16 AM »
Whatīs this ???
Can tune it as often i want, after a few minutes, about 5-10, itīs a little bit higher or deeper, 5-10 cents.
Sometimes all voices the same, sometimes differences in the voices. (Round robin, so i can see )
Deleted the tuning tables several times.
OS 201 is on it, i donīt want the new 2.04 because of the change from the velocity-holf-function (loudness).
If itīs a few cents out of tune after a few minutes i can switch power off and on and then itīs in tune, but also
only for a few minutes ?!?
Iīm afraid, thereīs a real defect that the synth "forgets" the tuningtable...
Anyone an idea ?

g3o2

Re: Prophet 10 loosing tune after a few minutes
« Reply #1 on: April 09, 2023, 09:49:18 AM »
Hi Chris,

Not a solution but just an idea: have you tried reinstalling the two pieces of firmware? Perhaps there is some corruption in the memory, just speculating here of course. Best to contact support I guess :-)

Enjoy the Easter Sunday,
Georges

Micky

Re: Prophet 10 loosing tune after a few minutes
« Reply #2 on: April 10, 2023, 03:08:24 AM »
Hi Chris,

Not a solution but just an idea: have you tried reinstalling the two pieces of firmware? Perhaps there is some corruption in the memory, just speculating here of course. Best to contact support I guess :-)

Enjoy the Easter Sunday,
Georges

Iīll try reinstalling next. Thank you...

Re: Prophet 10 loosing tune after a few minutes
« Reply #3 on: April 14, 2023, 01:54:58 AM »
It stores a calibration for every degree in temperature (displayed when you hit 'Tune'), so you need to build up calibrations for every temperature.  I cleared my calibration table then tuned it every two minutes or so as it warmed up, and since then I haven't really had any tuning issues.

Re: Prophet 10 loosing tune after a few minutes
« Reply #4 on: April 14, 2023, 03:14:13 PM »
Hi there - just stepping in. I highly recommend AGAINST calibrating the P10 every 2 minutes. That's not quite the way the calibration process works (interpolation is involved, which will be complicated by running too many calibrations). Instead, calibrate after it's been on for a few minutes, thereafter every 20 minutes or so until temperature plateaus. I hope this helps!
Sequential | Oberheim

Re: Prophet 10 loosing tune after a few minutes
« Reply #5 on: Yesterday at 02:15:23 PM »
I've been running into this as well... I haven't cleared any tuning tables and I only run the tuning when it is well out of tune. However, it does over time continue to drift sharp. For me, luckily, it takes more like 30 minutes before it becomes significant, but after a couple of hours it is way out of tune. Usually the oscillators are still in relative tune with each other, but not always. Like the OP, turning it off and back on again immediately seems to correct the issue without doing a retuning (and the temperature should not really be changing in any significant way for the 2 seconds I have it off).

I had chalked all this up to it being an analog synth (this is my first), but it sounds like this isn't the common experience?

I've also had an issue where after tuning completes all voices are completely messed up and are distorting (without increased level). Turning it off and back on again usually fixes this -- but sometimes it takes a few reboots. Retuning again may also fix this -- but I don't recall if I've confirmed that.

Re: Prophet 10 loosing tune after a few minutes
« Reply #6 on: Yesterday at 11:46:22 PM »
I've had some problems with tuning, having to push tuning button several times per day, then around 2 months ago, the problem has disappeared and I haven't pushed the button once since then.
So my message is just to say, yes, P10/P5 can stay perfectly in tune.

Re: Prophet 10 loosing tune after a few minutes
« Reply #7 on: Today at 04:48:37 PM »
So a quick update on what I was seeing. The way I was testing whether it was out of tune was using the built in A440 button and comparing to a init patch (plus a non-detuned Osc B added in to test it as well). What I was reliably seeing (and still seeing) is that it would be that playing the A key would be out of tune after a while with the A440. I assumed the A440 was correct.

Funny thing... the oscillators themselves and the synth actually were what were in tune. The A440 was going sharp over time. This surprised me as I kind of assumed this would be rock solid, and should be used for tuning. Turning the unit off and on again, the A440 is correct and the synth is unchanged. Go figure...

g3o2

Re: Prophet 10 loosing tune after a few minutes
« Reply #8 on: Today at 06:51:46 PM »
Now _that_ would have to be considered a bug, given that A440 is supposed to be an absolute reference tone. The fact that it comes back to normal after reboot gives rise to hope, for this hints at a software bug. Have you already reported this observation to support?

Re: Prophet 10 loosing tune after a few minutes
« Reply #9 on: Today at 07:01:47 PM »
Now _that_ would have to be considered a bug, given that A440 is supposed to be an absolute reference tone. The fact that it comes back to normal after reboot gives rise to hope, for this hints at a software bug. Have you already reported this observation to support?

I completely agree it would be a bug... However, I'm going to do some more testing to make sure I am seeing what I think I am seeing. It seems... implausible. And I've already confused myself on this issue before.