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

On 6/15/2019 8:52 PM, geoff wrote:
On 16/06/2019 7:53 AM, Paul wrote:
On 6/15/2019 5:12 AM, geoff wrote:
On 15/06/2019 11:57 PM, Paul wrote:
On 6/15/2019 4:53 AM, Paul wrote:
On 6/15/2019 3:25 AM, Mike Rivers wrote:
On 6/15/2019 2:30 AM, Paul wrote:
You won't believe this:Â* It was something like a 24 pin
header, with only 12 of the pins connected!

It's an easy mistake to make if the connector is in a tough-to-see
spot, as many of them are. I've seen socketed DIP ICs installed
with one row of pins all on the outside of the socket.

Â*Â*Â*Â*Â*Â* But I've never had a keyboard with an after-touch strip.
I must
say I don't really like it.

. . . .Â* how the aftertouch affects the voices, in some cases, it
either adds
a vibrato, or makes the note louder, or both.Â* 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!

I don't know if there's a way to globally turn off aftertouch (you
could disconnect the strip, I suppose), but it's almost certainly
a parameter in the patch that creates the voice. Factory presets
are usually created to show off as many features of the instrument
as possible. Get into the patch editor and you'll probably find
how to change what it modulates, or turn it off in that patch.

Or just don't press the keys so hard.Â*Â*


Â*Â*Â*Â*Â* Yes, I have the manual.Â* Just haven't looked into it in
detail yet.Â* I would imagine I would have to turn the aftertouch
off for each patch.

Â*Â*Â*Â*Â* Now that I've played with it a bit, it seems to be a fairly
useful function for voices like violins, where you sometimes want
heavy vibrato at the end of a note.

Â*Â*Â*Â*Â* But I have another problem:Â* The pitch wheel doesn't work, or
only
works intermittently.Â* Could be a bad potentiometer that needs to be
replaced.


Â*Â*Â*Â*Â*Â*Â*Â* Also, the both modulation wheel, and the pitch wheel on the
left, are both made of this soft rubber, and for some dumb reason,
the engineers made them side-by-side, such they they rub each other!

Â*Â*Â*Â*Â*Â*Â*Â* So as I turn one wheel, the other wheel follows it!

Â*Â*Â*Â*Â*Â*Â*Â* ****-poor design.Â* I might have to sand down one, or both
of the wheels, so they don't touch anymore.

Nothing a sharp blade can't fix !


Â*Â*Â*Â* Here's a pic:


https://www.gearslutz.com/board/atta...3-13.58.35.jpg


Â*Â*Â*Â* You can see that the pitch and modulation wheels are touching.

Â*Â*Â*Â* Really lousy design.Â* Yes, I might have to take a blade to it.





Yeah that rubberised finished that turns to goop after a decade or so.
Suggest disassemble the wheels, trim of the excess that is squidging
over the edges or the hard plastic wheel, and bevel it back a bit. All
with a sharp blade of some sort.


Yeah, it appears the rubber has expanded a bit, or perhaps the
axis of one of the wheels, has been knocked off alignment, hence
the touching and rubbing. Will probably cut some of the wheels.

Good news: 91% isopropyl alcohol has cleaned all the keys, so
they all work now! Funny thing: someone (Probably the same genius
that put only half of the header in!) put the rubber velocity
strips in backwards for about 1/3rd of the keys. One of the two
contacts is closer to the board for a reason! But kinda interesting
that most of the keys worked anyways, even with the rubber strip
in the wrong way!

Ok, next is the pitch and modulation pots. It looks like someone
spilled a drink in this part of the board, which would explain
a lot!

:/