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Paul[_13_] Paul[_13_] is offline
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Default Anyone have a Schematic for an Alesis QuadraSynth?

On 6/14/2019 12:36 PM, Paul wrote:
On 6/13/2019 8:06 PM, geoff wrote:
On 14/06/2019 1:33 PM, Paul wrote:
It works for the most part, except all the keys
from middle B and lower, do not work.

I'm hoping it will be something simple, like a loose
ribbon cable.

But a schematic would be helpful.


More helpful before you get too carried away would be a quick look at
the keyboard back-pcb where you will probably find a pcb-fracture, bad
jumper-wire between boards (or tarnished/corroded header),corroded
pcb-track or wire link, or a dead matrix diode.

Only after that should you need to start worrying about a schemtaic !


Â*Â* As I just said, I hope it's something simple, as you have mentioned.

Â*Â* But there's no harm in asking for the schematic now!


You won't believe this: It was something like a 24 pin
header, with only 12 of the pins connected!

UNBELIEVABLE. How could anyone be so foolish as
to hook up only one row of a 24 pin header? WOW.

So now the lower half of the keyboard work. I still have to
clean the contacts for several keys, and I should probably just clean
all of them, if I have the energy.

But I've never had a keyboard with an after-touch strip. I must
say I don't really like it. It's like you press a key, and there is yet
another 2nd level that you can push the key, when you push harder. Very
strange, and something I'm not sure I could get used to. And listening
to how the aftertouch affects the voices, in some cases, it either adds
a vibrato, or makes the note louder, or both. Doesn't seem too useful,
musically, but then again, it would depend of the kind of music you want
to create.

I hope there is an easy way to turn the aftertouch off!

:/