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Module quirks? VCO & VCM

2001-09-09 by John Papiewski

Does anybody besides me have the following trouble with their VCO or VCM
---

The sine wave output of all 3 of the VCO's (NTO & PCOx2) on my blue
voice panel have slight 'flyback' buzziness, audible especially at lower
frequencies. As if waveshaping is a little off. You'd expect that on
one but not all 3. I've checked out other people's Serge vco's, their
sinewaves are very good in this regard, don't know what it could be.

My VCM #2 (the middle one) is somewhat noisy, as in unwanted added white
noise.

Thanks

John P.

Re: Module quirks? VCO & VCM

2001-09-09 by echowind73@yahoo.com

--- In SergeModular@y..., John Papiewski <johnp@w...> wrote:

Show quoted textHide quoted text

> Does anybody besides me have the following trouble with their VCO or

VCM

> ---
>
> The sine wave output of all 3 of the VCO's (NTO & PCOx2) on my blue
> voice panel have slight 'flyback' buzziness, audible especially at

lower

> frequencies. As if waveshaping is a little off. You'd expect that

> one but not all 3. I've checked out other people's Serge vco's,

their

> sinewaves are very good in this regard, don't know what it could be.
>
> My VCM #2 (the middle one) is somewhat noisy, as in unwanted added

white

> noise.
>
> Thanks
>
> John P.

Ditto for my sine outputs (2xNTO, 2xPCO). Since they sound exactly
the same, I'd chalk it up to the nature of the design rather than
a manufacturing flaw. The buzziness sounds like it contains both
odd and even harmonics so it's not the case of the "sine" being
constructed by integrating a triangle wave. I've never been
annoyed by this because I use the sine outputs for modulation
or to add bass response. Also the pulse/square output from the NTO is
slightly duller than what I get by using a comparator.

If you've heard "clean" VCO's, do you have an idea
what year they were made?

I have no problems with the wave multiplier though. The sound is
exceptionally clean even at low input volumes.

Cheers,
--Harvey

Re: Module quirks? VCO & VCM

2001-09-09 by Jason Maston

Wilson and I checked out the Serge sine with the scope during the
Modcan/Serge shootout. Big triangular bump at the apex of the Serge
sine. Maybe this is what you're hearing.

J.

At 01:20 PM 9/9/01 -0500, you wrote:

Show quoted textHide quoted text

>Does anybody besides me have the following trouble with their VCO or VCM
>---
>
>The sine wave output of all 3 of the VCO's (NTO & PCOx2) on my blue
>voice panel have slight 'flyback' buzziness, audible especially at lower
>frequencies. As if waveshaping is a little off. You'd expect that on
>one but not all 3. I've checked out other people's Serge vco's, their
>sinewaves are very good in this regard, don't know what it could be.
>
>My VCM #2 (the middle one) is somewhat noisy, as in unwanted added white
>noise.
>
>Thanks
>
>John P.
>
>
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