MOTM

Despite the fact that I have more MIDI keyboards than I need and a perfectly
good Kenton pro-2000, I decided to take the DIY plunge and construct a CV
keyboard for contolling my modular.  As luck would have it, I found a very
nice 5 octave keyboard mechanism built into a very nice walnut case that has
3 contacts per key.  In addition, the precision resistors for the CV are
already installed.  And, in the appropriate place is a great spot for a
joystick or whatever.

Now, I have the easy part of this down pat. The pitch CV with the resistors.
I will probably stick in a nice DC op amp with a little summing network so I
have pitch bend with the joystick, and maybe put in an aux CV input for
other toys.  Now, the rest is wide open and I am in the learning mode.  The
arrangement of the contacts is such that they do not all have to close at
the same time.  So, looks like a velocity CV is possible too.

Under the generally accepted principal that "many heads are better than one"
I ask, "what would you include in such a controller?"  I am thinking pitch
CV out, joystick X and Y CV out with the ability to couple one axis of the
joystick to pitch CV internally, gate AND trigger out, velocity CV, and
maybe the ability to split the keyboard.  And, when using gate only, it
would be nice to be able to retrigger for the next keystroke (selectable).
I am planning to avoid DACs, PICs, matrix and all that stuff.  I have the
DAC accuracy in the Kenton.  What I want here is monophonic analog.

So, I would appreciate anyone's opinion of what they would choose to include
in the functionality.  And, any pointers toward additional reading material
or schematics that would help me become more familiar with the typical type
of circuity used in CV keyboards would be appreciated too.

Larry Hendry

Good luck. If you exclude all the things in your list, what were you
thinking would be able to generate velocity information?? How are you
planning on getting a keyboard split with a single chain of precision
resistors?

There are several ways to accomplish your goals, but your list of exclusions
have made your task much more difficult.

Tony

> -----Original Message-----
> From: J. Larry Hendry [mailto:jlarryh@...]
> Sent: Sunday, August 13, 2000 12:06 PM
> To: motm@egroups.com; synth-diy
> Subject: [motm] DIY keyboard
>
>
> Despite the fact that I have more MIDI keyboards than I need and
> a perfectly
> good Kenton pro-2000, I decided to take the DIY plunge and construct a CV
> keyboard for contolling my modular.  As luck would have it, I found a very
> nice 5 octave keyboard mechanism built into a very nice walnut
> case that has
> 3 contacts per key.  In addition, the precision resistors for the CV are
> already installed.  And, in the appropriate place is a great spot for a
> joystick or whatever.
>
> Now, I have the easy part of this down pat. The pitch CV with the
> resistors.
> I will probably stick in a nice DC op amp with a little summing
> network so I
> have pitch bend with the joystick, and maybe put in an aux CV input for
> other toys.  Now, the rest is wide open and I am in the learning
> mode.  The
> arrangement of the contacts is such that they do not all have to close at
> the same time.  So, looks like a velocity CV is possible too.
>
> Under the generally accepted principal that "many heads are
> better than one"
> I ask, "what would you include in such a controller?"  I am thinking pitch
> CV out, joystick X and Y CV out with the ability to couple one axis of the
> joystick to pitch CV internally, gate AND trigger out, velocity CV, and
> maybe the ability to split the keyboard.  And, when using gate only, it
> would be nice to be able to retrigger for the next keystroke (selectable).
> I am planning to avoid DACs, PICs, matrix and all that stuff.  I have the
> DAC accuracy in the Kenton.  What I want here is monophonic analog.
>
> So, I would appreciate anyone's opinion of what they would choose
> to include
> in the functionality.  And, any pointers toward additional
> reading material
> or schematics that would help me become more familiar with the
> typical type
> of circuity used in CV keyboards would be appreciated too.
>
> Larry Hendry
>
>
>
> 
>
>
>
>

Your knowledge on the subject is so far ahead of mine on this Tony, that I
don't even feel like I can ask intelligent questions.  My list of desires
and exclusions is nowhere near firm.  It is just my initial thoughts.  For
example, splits maybe out of the question.  As far as velocity information,
I am totally in the dark as to how.  Just thinking out loud, it would seem
that some kind of timer between two contacts could be used.  When I said
avoid DAC, I guess I was thinking about the pitch CV.  Obviously, something
like this would be most certainly be required to converting timing into
voltage for the velocity thing.  My ignorance on the subject is certainly
showing, and I am just looking for a starting place from guys well versed in
the subject like yourself.  Any, and all input (including telling me I need
to re-examine my wants and exclusions) is MOST welcome.
Larry Hendry


----- Original Message -----
From: Tony Karavidas <tony@...>
To: <motm@egroups.com>
Sent: Sunday, August 13, 2000 2:29 PM
Subject: RE: [motm] DIY keyboard


Good luck. If you exclude all the things in your list, what were you
thinking would be able to generate velocity information?? How are you
planning on getting a keyboard split with a single chain of precision
resistors?

There are several ways to accomplish your goals, but your list of exclusions
have made your task much more difficult.

Tony

> -----Original Message-----
> From: J. Larry Hendry [mailto:jlarryh@...]
> Sent: Sunday, August 13, 2000 12:06 PM
> To: motm@egroups.com; synth-diy
> Subject: [motm] DIY keyboard
>
>
> Despite the fact that I have more MIDI keyboards than I need and
> a perfectly
> good Kenton pro-2000, I decided to take the DIY plunge and construct a CV
> keyboard for contolling my modular.  As luck would have it, I found a very
> nice 5 octave keyboard mechanism built into a very nice walnut
> case that has
> 3 contacts per key.  In addition, the precision resistors for the CV are
> already installed.  And, in the appropriate place is a great spot for a
> joystick or whatever.
>
> Now, I have the easy part of this down pat. The pitch CV with the
> resistors.
> I will probably stick in a nice DC op amp with a little summing
> network so I
> have pitch bend with the joystick, and maybe put in an aux CV input for
> other toys.  Now, the rest is wide open and I am in the learning
> mode.  The
> arrangement of the contacts is such that they do not all have to close at
> the same time.  So, looks like a velocity CV is possible too.
>
> Under the generally accepted principal that "many heads are
> better than one"
> I ask, "what would you include in such a controller?"  I am thinking pitch
> CV out, joystick X and Y CV out with the ability to couple one axis of the
> joystick to pitch CV internally, gate AND trigger out, velocity CV, and
> maybe the ability to split the keyboard.  And, when using gate only, it
> would be nice to be able to retrigger for the next keystroke (selectable).
> I am planning to avoid DACs, PICs, matrix and all that stuff.  I have the
> DAC accuracy in the Kenton.  What I want here is monophonic analog.
>
> So, I would appreciate anyone's opinion of what they would choose
> to include
> in the functionality.  And, any pointers toward additional
> reading material
> or schematics that would help me become more familiar with the
> typical type
> of circuity used in CV keyboards would be appreciated too.
>
> Larry Hendry
>
>
>
>
>
>
>
>

In a message dated 8/13/2000 12:11:41 PM, jlarryh@... writes:

>As luck would have it, I found a very
>nice 5 octave keyboard mechanism built into a very nice walnut case that
>has
>3 contacts per key.  In addition, the precision resistors for the CV are
>already installed.  And, in the appropriate place is a great spot for a
>joystick or whatever.


Do you know what this was from? Very lucky indeed!

If space would permit you might think of putting in two joysticks or a wheel. 
This would allow you to control the obvious things like pitch and filter 
cutoff frequency as well as having a separate way of controlling some sort of 
modulation (like cross modulation between two VCOs) -- just a thought.


>So, looks like a velocity CV is possible too.
>
 I am thinking pitch
>CV out, joystick X and Y CV out with the ability to couple one axis of
>the
>joystick to pitch CV internally, gate AND trigger out, velocity CV, and
>maybe the ability to split the keyboard.  And, when using gate only, it
>would be nice to be able to retrigger for the next keystroke (selectable).
>I am planning to avoid DACs, PICs, matrix and all that stuff. 

I'd think that velocity and keyboard splitting would be a lot of extra work, 
and easier with some sort of uP than hardware -- better suited to Paul's 8051 
project with a scanning keyboard (plus all the other stuff you could make 
that do).


I think a "basic" 3 buss keyboard project can be found in Barry Klein's book 
and Tomg used to have a keyboard PCB at his site.

Good luck with this!
JB

> ----- Original Message -----
> From: <jwbarlow@...>
> Do you know what this was from? Very lucky indeed!

It is reported (without any attention on my part) to have been purchased
from Dr. Moog himself, by the buyer before me.  I found it on e-bay  It's
past owner ship was not my concern.  I just liked the price and challenge to
"learn by doing."

> If space would permit you might think of putting in two
> joysticks or a wheel.  This would allow you to control
> the obvious things like pitch and filter cutoff frequency
> as well as having a separate way of controlling some
> sort of  modulation (like cross modulation between two
> VCOs) -- just a thought.

I am "looking" for thoughts like this.

> I'd think that velocity and keyboard splitting would be
> a lot of extra work, and easier with some sort of uP than
> hardware -- better suited to Paul's 8051 project with a
> scanning keyboard (plus all the other stuff you could make
> that do).

Probably beyond my ability.  I am not interested in uP.

> I think a "basic" 3 buss keyboard project can be found in
> Barry Klein's book and Tomg used to have a keyboard PCB
> at his site.

Great.  I am not familiar with the Klein book (more of my ignorance
showing).  What the book title?  I will check out Tomg's site too.

> Good luck with this!

I am going to need it.  It will be a great learning experience since I am
obviously not adequetly prepared to tackle the job with what I know today.

Larry

On Sun, 13 Aug 2000, J. Larry Hendry wrote:

> example, splits maybe out of the question.  As far as velocity information,
> I am totally in the dark as to how.  Just thinking out loud, it would seem
> that some kind of timer between two contacts could be used.  When I said
> avoid DAC, I guess I was thinking about the pitch CV.  Obviously, something
> like this would be most certainly be required to converting timing into
> voltage for the velocity thing.  

  (crow butts in)

  Where did you come across this keyboard/case?  If I had one I might see
about a little PIC to sort things out, heh heh

Crow

/**/

Speaking of Tom G's site, what's the URL?

Moe

----- Original Message -----

From: The Old Crow <oldcrow@...>
(crow butts in)

Where did you come across this keyboard/case?  If I had one I might see
about a little PIC to sort things out, heh heh

I am planning not to have any PIC or uP stuff (mostly because I don't know
squat about it).  I want to keep it as simple as reasonable to get some of
the features I would like to have.  Time to start reading up on some of the
"traditional" circuits.

I purchased the keyboard on E-bay, of all places.  I should have it by mid
week.

Larry H

In a message dated 8/13/2000 1:05:25 PM, jlarryh@... writes:

>What the book title?

I think you meant to say, "What the book?"

The book is called: "Electronic Music Circuits" by Barry Klein. He's active 
on diy and sells photocopies of his book. A lot of CEM and SSM stuff, and 
some Electronotes things, but also many good explanations of basic synth type 
circuits.

JB