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P12 Aliasing / High Frequency ringing

P12 Aliasing / High Frequency ringing
« on: May 30, 2018, 07:12:16 AM »
Hi!
I recently got a used prophet 12, and have noticed a weird ringing in the sound.
Have not yet been able to locate what generates it, but i'm able to remove it if i turn the high pass filter above value 50.

I can best describe it as a high frequency digital ringing / aliasing, but it seems to stem from low frequency content, and is best heard with the low pass filter turned down low and with mellow sounds.

Have updated os, and calibrated the filters several times but no improvement.


Someone here familiar with the issue, or have similar experiences?


Cheers!


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updated the post with an image displaying the ring above 10k
the patch is a bass heavy, low passed pad sound.
« Last Edit: May 30, 2018, 07:40:03 AM by tvdt »

Re: P12 Aliasing / High Frequency ringing
« Reply #1 on: May 30, 2018, 08:24:18 AM »
Is your P12 connected via USB? If you search the forums for 11khz you will find other users with similar issues.

dslsynth

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Re: P12 Aliasing / High Frequency ringing
« Reply #2 on: May 30, 2018, 08:50:50 AM »
Contact DSI support directly. They will help you get it sorted out. I have seen such issues resolved via board swaps in the past. May happen these days too.

Good luck with your new machine!
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Re: P12 Aliasing / High Frequency ringing
« Reply #3 on: May 30, 2018, 09:01:51 AM »
Thanks for the replies, guys!

The issue seems unrelated to usb-connections.
Have written DSI support directly now.
A board swap sounds expensive :-/

cheers



dslsynth

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Re: P12 Aliasing / High Frequency ringing
« Reply #4 on: May 30, 2018, 09:11:47 AM »
A board swap sounds expensive :-/

It used to be something like $25 plus shipping possibly plus an extra fee which is returned once your board have arrived back at DSI HQ. So while not cheap its actually quite affordable compared to other manufacturers. Not sure what the current prices are though. Maybe DSI can detail on that here?
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cp -f $0 $HOME/.signature

Re: P12 Aliasing / High Frequency ringing
« Reply #5 on: May 31, 2018, 03:59:28 PM »
You've got it right, nothing has changed in that regard.


tvdt-

I'm sorry to hear you're having trouble with your Prophet 12, I see you've already contacted our dedicated support channel so we'll get you sorted out quickly.
SEQUENTIAL

Re: P12 Aliasing / High Frequency ringing
« Reply #6 on: June 03, 2018, 02:34:58 AM »
It happened to me, (if its the same issue).
Check the pitch of the oscillators, mine was all the way up when launching my DAW with the synth ON.
I dont know what was doing that but i turned off NPRC and now its ok.

Ole

Re: P12 Aliasing / High Frequency ringing
« Reply #7 on: December 01, 2020, 03:30:37 AM »
Hi there, i have just found this thread after finding same strange and irritating filter related noise artifacts on my second-hand bought P12 module. Something the pre-owner may have not noticed.
Itís a very early unit with SN <20 and i can reproduce the same behaviour described above on an init patch with LPF cutoff around 60 and resonance around 65, but also if i close the filter some more and rising resonance, sounds like digital artefacts and and hear it across the patches in the background, some kind of ringing tone which gets louder from voice 1 to voice 12, playing repeated notes. also there is some slight amount of pitch change between the voices. And yes, no USB cable attached. Re-installed firmware and calibrated filters, no changes on that behaviour. Going to cantact DSI support with an audio-file about this, and i hope they are still the best customer service in the world :) Iím totally in love with the sound and potential of the P12 and i can see itís still on sale and available after so many years! Best from Berlin, Ole

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Re: P12 Aliasing / High Frequency ringing
« Reply #8 on: December 02, 2020, 10:05:36 AM »
The same thing happened to me!!  I bought a mint condition Prophet 12 Keyboard from Reverb.com 6 months ago and Sequential support are so amazing I just had to remove the main voice board and send it to them to repair it, they were so fast and totally fixed the problem for only $25...they are the best and so is the Prophet 12!
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