Suddenly...Jittery, Unstable Sounding Analogue Square Waves

[Grokaknock]

Greetings!

Over the last few days I have noticed that the square waves on all the analogue oscillators sound jittery. I can't get a smooth square wave out of the Prologue anymore. It sounds very unstable, like something is modulating the oscillator but this is happening in an initialized state.

Things I've already tried....

1. Factory Reset
2. Unplugging all cables except for power and audio
3. I tried a completely different power source
4.The synth is already loaded with the latest OS, Voice and Panel updates

I've recorded an mp3 file so you can hear for yourselves what it sounds like. The Prologue is the first synth to play. Every other note is the Sequential OB-6 so you have some contrast. It is most obvious at 18 seconds but it is easy to hear all the way through the file.

https://soundcloud.com/rotundness/prolg-sqr-wave-jitter

If anyone has a minute, could you please check your square waves for smoothness and purity of tone and report back here?

Thanks!!!

[NickZoll]

Hi, i checked your file and I must say I do hear some highspeed vibrations but not on every particular note, only some of them (or i am missing something).
I tried my p16 and there is nothing like these. Don’t know maybe it is temperature dependent or something else. I also noticed in your record square seems to be a little bit duller, are you sure the filter was fully open?

[Grokaknock]

Hi, i checked your file and I must say I do hear some highspeed vibrations but not on every particular note, only some of them (or i am missing something).
I tried my p16 and there is nothing like these. Don’t know maybe it is temperature dependent or something else. I also noticed in your record square seems to be a little bit duller, are you sure the filter was fully open?

Thanks for the reply...I think you didn't completely read my post. Every other note in the sound file is the OB-6 for contrast. The Prologue plays the 1st note. Maybe I'll upload another file without the 2nd synth if it's confusing.

This test was started from an initialized state on both synths. (The Default Empty Preset) I made sure that nothing was being modulated.

[Synthee]

The square wave on my PL16 has always sound strange I think, Im not sure if its correct or not?
This is a file were you can hear that some of the voices sound more dull than the others:

<iframe width="100%" height="300" scrolling="no" frameborder="no" allow="autoplay" src="https://w.soundcloud.com/player/?url=ht ... "></iframe>

[NickZoll]

I think I got it right. Prologue goes first and it sounds duller than ob6. I mean not every prologue note sounds weird to my ears but there is some movement going on, don’t know if it is malfunction or just specificity of the osc

[NickZoll]

Synthee,
There is definitely some filtering going on. I don’t have anything like this
Is it an init program?

[jimknopf]

@Grokaknock

I have the same kind of dirt in my square waves, maybe slightly less obvious, but definitely there.

But I became aware that the Prologue is no clean sounding synth at all, from first trying it in the store onwards. This kind of sound has a pro and a con side from my view.
- Con: you literally NEVER get pure sounds from this synth, like from a Prophet 6 or OB6. There's lots of dirt and even kind of cross-talk noise (like in a B3 signal chain) in it's circuits.
- Pro: all these slight sound inconsistencies together make this synth sound quite alive

Since you rarely have all open filters, and a lot of other things are going on in a mix or live band, the resulting compromise (limited audible dirt from an else vivid sounding synth) can be handled IMHO - in contrast to the tuning issue, which is a complete no go to me.


@Synthee: I do not have your filtering jumps with duller sounding squares here in my Prologue.

[Grokaknock]

Thanks for all the replies people. So no one's square waves are fluctuating like this? I sent it to Korg support and Sweetwater and already heard back from both. They definitely hear what I'm hearing and that is all that matters for now. Gonna have to send it in for repair.

I forgot to mention you might have to play the file on something better then computer speakers to hear it clearly. I've played and used synths with "buzzy" square waves many times but this is something else entirely.

[NickZoll]

I used my beyerdynamic 880 to check it out and the same headphones to test my synth. As I said i do have some movement but not as yours and your record sounds like a bit filtered compared to my prologue. I hope they will fix it. BTW if you aven’t done it so far you may want to register your prologue to get 2 extra years of waranty from korg