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SEQUENTIAL/DSI => Prophet => Prophet 12 => Topic started by: tvdt on May 30, 2018, 07:12:16 AM

Title: P12 Aliasing / High Frequency ringing
Post by: tvdt 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!


-------

updated the post with an image displaying the ring above 10k
the patch is a bass heavy, low passed pad sound.
Title: Re: P12 Aliasing / High Frequency ringing
Post by: mekohler 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.
Title: Re: P12 Aliasing / High Frequency ringing
Post by: dslsynth 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!
Title: Re: P12 Aliasing / High Frequency ringing
Post by: tvdt 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


Title: Re: P12 Aliasing / High Frequency ringing
Post by: dslsynth 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?
Title: Re: P12 Aliasing / High Frequency ringing
Post by: Robot Heart 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.
Title: Re: P12 Aliasing / High Frequency ringing
Post by: Mechamilk 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.
Title: Re: P12 Aliasing / High Frequency ringing
Post by: Ole 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.
It’s 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 :) I’m totally in love with the sound and potential of the P12 and i can see it’s still on sale and available after so many years! Best from Berlin, Ole
Title: Re: P12 Aliasing / High Frequency ringing
Post by: S Y Z Y G Y X 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!
Title: Re: P12 Aliasing / High Frequency ringing
Post by: dhoinjo on October 05, 2022, 02:45:57 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.

Hello, is this still the case, now that the P12 is discontinued? I have bought a second hand unit and it has the same problem. Contacted support last week, but haven't received a reply. I hope that a synth that is only discontinued so shortly still can get support, and that the great customer service of DSI/Sequential hasn't changed now that a big player has stepped in and bought the firm. Kind regards, H
Title: Re: P12 Aliasing / High Frequency ringing
Post by: dhoinjo on October 08, 2022, 05:43:19 AM
I contacted support over a week ago, to ask if they could still help me with this. No reply. I filed two tickets. Driving me nuts. Really bad customer support if you ask me, not even a polite "no we can't help you". Nothing. I'd expect for support and repairs if a synth is discontinued for at least a couple of years, or am I wrong?
Title: Re: P12 Aliasing / High Frequency ringing
Post by: Sacred Synthesis on October 08, 2022, 03:07:14 PM
Sequential support is excellent, but once in a while there's a glitch.  They continue to support all the instruments they've made, going back to about 2006.  I would be persistent but patient.
Title: Re: P12 Aliasing / High Frequency ringing
Post by: LPF83 on October 08, 2022, 03:46:06 PM
I contacted support over a week ago, to ask if they could still help me with this. No reply. I filed two tickets. Driving me nuts. Really bad customer support if you ask me, not even a polite "no we can't help you". Nothing. I'd expect for support and repairs if a synth is discontinued for at least a couple of years, or am I wrong?

One factor to consider (as someone who is reminded of this regularly in their daily job) when you have something like a support ticket system that relies on e-mail for communication, there are a gazillion opportunities for transactional emails (email replies from said system for example) to not reach their destination.   Client side and server side spam filters the recipient forgets about or never knew existed, intermediate sender reputation lists, security software all over the place, etc.   It's honestly kind of amazing that anyone is able to receive any emails at all these days.  So it is very possible that someone has followed their internal protocol and you're still not receiving a reply for whatever reason.... in those cases I usually explore as many alternative possibilities as I have access to in order to get in touch with whoever I need to get in touch with.