Korg MS20 mini warbly sound

[DrZaiusBE]

Hi

I recently purchased a Korg MS20 mini. I'm noticing a distict warbly sound. The warble's pace speeds up when I press a higher note. Is this normal?

I read something about possible tuning probems so I checked both VCO's seperatly to see if the tuning was right, but it isn't.

Thanks in advance.

[roblabs]

Do you have everything on default parameters? (factory settings, ie no patch cables, no modulation, etc)

[DrZaiusBE]

Everything is set to the 'normal' settings. To test the tuning I used the settings in the service manual for the MS-20.

[Re-Member]

This sounds normal to me. When you stack two oscillators on each other, the waveforms often create weird patterns of sound because the cycle of the waveforms are never truly in sync. At higher notes, the patterns are more noticeable because the speed of the cycle is increased. There's also the fact that since they are VCOs, the tuning is never 100% accurate, so you'll always have this subtle chorus effect drifting in and out.

Long story short, what you are hearing is the "organic" behavior of analog oscillators.

[DrZaiusBE]

Oh I see. Thanks for your answer.

[Redmond Barry]

When you just have one oscillator mixed in does it continue to warble? Or just when both are mixed together. And by warble, do you mean the pitch warbling up and down?

[DrZaiusBE]

When I use one it doesn't warble.

I think it's the picth. And when I move up or down the keys the warbling tempo goes up and down.
When I adjust the Pitch knob it also changes it's tempo.

[X-Trade]

Yeah, that's the interaction of the slightly different pitches of the two oscillators. It's normal and is actually considered kind of desirable. It's a bit like when you are tuning a guitar using two strings fretted at the same note. The result is a kind of chorusing as the two waves drift in and out of phase, cancelling eachother out.

[DrZaiusBE]

I'm kinda new to analog synthesizers so I was a bit confused. Thanks again for the replies.

[el_hombre]

Cheers, thread!
I was noticing my mini doing this on Wednesday but not knowing why...
Came on and read this in the weekend, did some tweaking of the tuning of osc 2 and sure enough, gone!
Nice one!

[DrZaiusBE]

How do you tweak the tuning of a single osc?

[Redmond Barry]

That's the wonderful world of VCO's! I believe with DCO based synths you can get the oscillators to "lock", but with Mini you'll never get it to have the two VCOs perfectly in tune together so there will always be some phasing. I personally consider it desirable as well. I don't have a Mini (yet!), but if I remember correctly the only individual OSC tuning you have is VCO 2's pitch control. Of course there's the master tune as well.

[el_hombre]

Yeah that's the one. VCO2 has a pitch ajustment control which is really nice for tuning the oscillator. You can get the tuning pretty much perfect, slightly out of tune, or dial in a harmony or whatever suits.
The funny thing I've been noticing in the last week is that when I have VCO 1 on triangle wave, that VCO is really quiet on the bottom keys. Anyone heard of this one?
(thought I'd just ask in here instead of starting a new thread, maybe we just need a 'MS20 Mini problem solving for noobs' thread...)

[Redmond Barry]

If you watch Automatic Gainsay's videos you can hear the triangle waves (sorry I don't know how to embed, if you can):

MS-20 Mini (triangle at 1:15)

http://www.youtube.com/watch?v=6Noo3uoR ... vs&index=2

Sounds like it's "normal" to me, what you are describing (gets louder as you go up). The MS-20 is very quirky. I had an MS-10 and it had some quirks too.

[roblabs]

Generally speaking, this is the nice thing about analogs - you learn so much about synthesis from them. And you learn to use the quirks - and (just like with any gear) limitations - and make them work for you.