Patches and discussion for Ensoniq VFX family

On Friday, November 22, 2002, at 03:33 AM, aikondammit wrote:

> Does anyone know how to clean or replace one of the sliders on the
> VFX SD?  My problem is that when I play back a sequence that I am
> working on, the playback tempo changes on its own.  When I move the
> slider, I can get it back to where I want for a bit before it changes
> on its own again.
>
> I think that the slider is maybe corroded and causing this problem.
> Came to this conclusion after finding some ?rust? that is showing on
> the headphone jack.  I bought this from Ebay a couple months ago from
> someone that apparently did not store it very well.
>
> If you have any other ideas about what may be causing this please let
> me know.
>

This is caused usually by jitter on the ADC that samples the slider. 
Corrosion may make it worse, but its not necessarily the cause - it 
will happen even on a clean slider track. The only real solution is to 
make sure that the tempo control isn't selected when you start - select 
LOOP or something first.  The on/off parameters are a lot less 
susceptible to slider jitter unless the slider is positioned right on 
the 50% mark where it will jitter between on/off. Also making sure that 
the slider is at an extent (top or bottom) will reduce any chance of 
jitter affecting things.

The fact that its happening often is perhaps a sign that you are having 
extra jitter from a dirty slider, you can probably cure this by getting 
some potentiometer cleaner fluid and spraying a little into the slider 
track and moving the slider back and forth a few times. But even on a 
clean slider it WILL happen over time.

I often suffer from jitter in the same way if I accidently leave the 
transpose page open, and i'll come back after an hour or two to find 
that the setting has ended up at -4 octaves :)