Prophet 10 audio clipping

Prophet 10 audio clipping
« on: July 29, 2022, 12:25:19 AM »
My Prophet 10 exhibits a pronounced clipping (audio outputs main+headphones) after some hours of use. This is temporarily remedied by running the calibration again. Sequential support suggested the following procedure, to avoid over-calibration:

1. Discard calibration (Record+Tune)
2. Power cycle
3. After 2 minutes: Tune first time
4. After 20 minutes: Tune second time
5. After another 20 minutes: Tune third time

The clipping reappears after a few days of operation.

Has anybody in this forum noticed the same or similar problem on their P10?
-------- OS versions ----------
   • Main OS:  2.0.1
   • Panel OS: 1.1.1
   • Main FPGA OS: 1.0.2
   • Expansion FPGA OS: 000

Prophet-10, OB-6 Keyboard and Desktop, MEK, Poy Evolver, Pro-2, VintageVibe Piano, Wurlitzer 206, Hohner Clavinet E7

Re: Prophet 10 audio clipping
« Reply #1 on: July 29, 2022, 11:34:53 AM »
My Prophet 10 exhibits a pronounced clipping (audio outputs main+headphones) after some hours of use. This is temporarily remedied by running the calibration again. Sequential support suggested the following procedure, to avoid over-calibration:

1. Discard calibration (Record+Tune)
2. Power cycle
3. After 2 minutes: Tune first time
4. After 20 minutes: Tune second time
5. After another 20 minutes: Tune third time

The clipping reappears after a few days of operation.

Has anybody in this forum noticed the same or similar problem on their P10?
-------- OS versions ----------
   • Main OS:  2.0.1
   • Panel OS: 1.1.1
   • Main FPGA OS: 1.0.2
   • Expansion FPGA OS: 000

Mine exhibited that behavior as well and it disappeared after powering it off and leaving it for about 2 hours. I opened a ticked with Sequential but couldn't trace the problem because like I said it disappeared. Maybe it's temperature related but I can't say for sure.

Re: Prophet 10 audio clipping
« Reply #2 on: July 29, 2022, 12:05:16 PM »
My Prophet 10 developed a problem but I'm not sure if it's the same problem you had. Sequential support hit the ball out of the park taking care of me and they resolved the problem. Here's a description of the problem I had: On an intermittent basis, the sound from my Prophet 10 became quite distorted, and the volume increased dramatically (vol =3 was as loud as vol = 10 when functioning normally). If this sounds like your problem, who ya gonna call? (Sequential Support)
Prophet 10 Rev4, OB-X8, Moog One, Rhodes Mk8, Osmose, OB-6 desktop, Trigon 6 Desktop, Kawai VPC-1, Steinway D

Re: Prophet 10 audio clipping
« Reply #3 on: August 16, 2022, 10:53:02 AM »
Update: Sequential support think this is a hardware problem, sent my P10 to repair today
Prophet-10, OB-6 Keyboard and Desktop, MEK, Poy Evolver, Pro-2, VintageVibe Piano, Wurlitzer 206, Hohner Clavinet E7

g3o2

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Re: Prophet 10 audio clipping
« Reply #4 on: August 16, 2022, 05:32:02 PM »
the volume increased dramatically (vol =3 was as loud as vol = 10 when functioning normally).

I would not even know how loud vol 10 is. I can’t turn the knob any further than 3-4, beyond it will be just too loud. Is this normal btw? Not that I’d feel the urge to turn it up that loud, only wondering because usually I can set my synths to 2/3 vol without any issue …

Re: Prophet 10 audio clipping
« Reply #5 on: August 17, 2022, 06:27:08 AM »
The volume knob setting may vary widely depending on each user's setup. Personally, I am using a "reamp" between the Prophet and my first pedal and having the volume at 10 seems to be working well and provides a good signal to noise ratio.
Prophet 10 Rev4, OB-X8, Moog One, Rhodes Mk8, Osmose, OB-6 desktop, Trigon 6 Desktop, Kawai VPC-1, Steinway D

Re: Prophet 10 audio clipping
« Reply #6 on: August 17, 2022, 07:28:04 AM »
The volume knob setting might be interesting enough to be its own topic apart from the "audio clipping" topic? There might be interesting issues as to how people gain stage volume with pedals or in other contexts?
Prophet 10 Rev4, OB-X8, Moog One, Rhodes Mk8, Osmose, OB-6 desktop, Trigon 6 Desktop, Kawai VPC-1, Steinway D

LPF83

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  • 1437
Re: Prophet 10 audio clipping
« Reply #7 on: August 17, 2022, 03:51:59 PM »
The volume knob setting might be interesting enough to be its own topic apart from the "audio clipping" topic? There might be interesting issues as to how people gain stage volume with pedals or in other contexts?

I have my template default track settings gain staged to -16db in Cubase for pregain (though realistically it almost always gets turned up... that's more for getting more precise resolution out of the gain slider than anything else).  Usually it's just a matter of adjusting the master vol on the P10 in conjunction with the knobs for the preamps on my audio interface.
Prophet 10, OB-X8m, Prophet 6, OB-6, 3rd Wave, Prophet 12m, Prophet Rev2-16, Toraiz AS-1, Pro 2, Virus TI2, Moog SlimPhatty, Hydrasynth desktop, Korg Minilogue XDm, Roland JP-8080, Roland System-8, Roland SPD-SX SE / Octapad, Maschine, Cubase/Ableton/Akai MPC

Re: Prophet 10 audio clipping
« Reply #8 on: August 18, 2023, 12:42:16 PM »
I recently encountered a similar distorted type of sound.  I contacted Sequential support, and was told the main PCB and/or expansion boards were defective.  I've paid a deposit for replacement boards, and I'm waiting for them to be delivered. 

What was the cause of your issue?  How did Sequential resolve it? 


My Prophet 10 exhibits a pronounced clipping (audio outputs main+headphones) after some hours of use. This is temporarily remedied by running the calibration again. Sequential support suggested the following procedure, to avoid over-calibration:

1. Discard calibration (Record+Tune)
2. Power cycle
3. After 2 minutes: Tune first time
4. After 20 minutes: Tune second time
5. After another 20 minutes: Tune third time

The clipping reappears after a few days of operation.

Has anybody in this forum noticed the same or similar problem on their P10?
-------- OS versions ----------
   • Main OS:  2.0.1
   • Panel OS: 1.1.1
   • Main FPGA OS: 1.0.2
   • Expansion FPGA OS: 000

Re: Prophet 10 audio clipping
« Reply #9 on: August 19, 2023, 05:01:55 PM »
Sequential support suggested the following procedure, to avoid over-calibration…
I did not know that something like over-calibration exists for the P5/10. Strange. I always thought of the opposite - the more the better (more stable)