Xpantastic!

Hello Matt,
When using the FM on an Xpander / M12 you should expect the tuning to
remain consistant between each of the voices. However because of the
very slight drift of the analog VCO's you may find the tone will change
as you play in different ranges of the keyboard.  In other words,
If you play the same note repetedly ( with an arppigiator for example)
the tuning should be consistant as you rotate through the voices, but
playing notes at different ranges of the keyboard the tone will change.
B.T.W. The (DAC) control element used for the FM is very precise
compared to the (VCA) control elements used in other parts of the synth.

There are many things that could cause this, but a bad solder connection
or slight oxidation/corrosion between an IC pin and the IC socket, seems
most likly, because you report moving the synth changes it's
performance.

- Karl

--- In xpantastic@yahoogroups.com, "mattvrazo" <vrazomatt@...> wrote:
>
> I had posted some time ago on here about uneven resonances on my
xpander-bizarrely, it corrected itself when I re-mounted the unit on my
stand and the resonances are perfectly in tune.
>
> However, I noticed when cranking up the FM last night that despite my
best efforts to untune and then retune, I could not get the FM
consistent across the voices. They are not wildly different, but
different enough to make chromatic playing difficult.
>
> There is no consistency between which voices are more in tune with
each other either, so I can't immediately say it's chip related.
>
> So I guess my question is-should I expect the voices to be identical
when full FM (on filter) is used? I seem to recall this being possible
when I first got my unit, but I don't actually use FM that often.
>