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CV Keyboards

CV Keyboards

2000-05-30 by ivancu@aol.com

I know this is somewhat silly, but is anyone out there still making a
control-voltage keyboard? No, I don't want to use a MIDI keyboard with a
MIDI-to-CV converter.

Ivan

Re: [motm] CV Keyboards

2000-05-30 by Nathan Hunsicker

i've been searching for a while now and have found nothing. other than the
novation basstation keyboard with a tiny keyboard and a cv out (which i
belive is just a built in midi to cv convertor) I don't know of any in
production. I have been dreaming of a DIY project consisting of a standard
keyboard with individual tuning controls for each key (mind you this would
require expensive resistor chains and 48 pots for a 4 octave keyboard but
would be a great hit for the microtonality guys. I'd also like to include a
keyboard split to convert the keyboard into 2 seperate 2 octace keyboards
(i'm not even going to attempt polyphony) The final cost would prob. be
well over what a decent midi controller and MIDI/CV convertor would cost. I
know this really doesn't help, but it's food for thought. -Nate

Show quoted textHide quoted text
>
>I know this is somewhat silly, but is anyone out there still making a
>
>control-voltage keyboard? No, I don't want to use a MIDI keyboard with a
>
>MIDI-to-CV converter.
>
>
>
>Ivan
>
>
>
>

RE: [motm] CV Keyboards

2000-05-30 by Dave Bradley

You may have to DIY it yourself. When I built my original EMu modular from
submodules, I bought the digital board for the mono keyboard, and wired it
up to a Pratt and Reed keyboard myself. The circuit for the Emu kbd is
probably available somewhere. It was much stabler than resistor chains, had
the variable lin/exp portamento like the new MOTM Lag Processor, and had a
neat feature where you could switch the bottom octave to separate gate
outputs. I don't believe it had a microprocessor, but I could be wrong.

Dave Bradley
Principal Software Engineer
Engineering Animation, Inc.
daveb@...

Show quoted textHide quoted text
> -----Original Message-----
> From: Nathan Hunsicker [mailto:nate@...]
> Sent: Tuesday, May 30, 2000 11:55 AM
> To: motm@egroups.com
> Subject: Re: [motm] CV Keyboards
>
>
> i've been searching for a while now and have found nothing. other than the
> novation basstation keyboard with a tiny keyboard and a cv out (which i
> belive is just a built in midi to cv convertor) I don't know of any in
> production. I have been dreaming of a DIY project consisting of a standard
> keyboard with individual tuning controls for each key (mind you this would
> require expensive resistor chains and 48 pots for a 4 octave keyboard but
> would be a great hit for the microtonality guys. I'd also like to
> include a
> keyboard split to convert the keyboard into 2 seperate 2 octace keyboards
> (i'm not even going to attempt polyphony) The final cost would prob. be
> well over what a decent midi controller and MIDI/CV convertor
> would cost. I
> know this really doesn't help, but it's food for thought. -Nate
>
> >
> >I know this is somewhat silly, but is anyone out there still making a
> >
> >control-voltage keyboard? No, I don't want to use a MIDI keyboard with a
> >
> >MIDI-to-CV converter.
> >
> >
> >
> >Ivan
> >
> >
> >
> >
>
>
>
>
> ------------------------------------------------------------------------
> Failed tests, classes skipped, forgotten locker combinations.
> Remember the good 'ol days
> http://click.egroups.com/1/4053/5/_/529958/_/959705815/
> ------------------------------------------------------------------------
>
>

Re: [motm] CV Keyboards

2000-05-30 by skinny bastard

I'm working on mine. Pretty limited though.
Analogue Systems has one that they're going to have available within a month
or two, but expect it to be anywhere from 1500 to 2000.


>From: ivancu@...
>Reply-To: motm@egroups.com
>To: motm@egroups.com
>Subject: [motm] CV Keyboards
>Date: Tue, 30 May 2000 12:10:54 EDT
>
>I know this is somewhat silly, but is anyone out there still making a
>control-voltage keyboard? No, I don't want to use a MIDI keyboard with a
>MIDI-to-CV converter.
>
>Ivan

________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com

RE: [motm] CV Keyboards

2000-05-30 by Brousseau, Paul E (Paul)

1500-2000 US Dollars? That thing had better have multiple CV outs,
velocity, aftertouch, and a Learn-Classic-Piano-In-21-Days book included!
;)

--PBr

Show quoted textHide quoted text
> -----Original Message-----
> From: skinny bastard [SMTP:skin_job@...]
> Sent: Tuesday, May 30, 2000 12:50 PM
> To: motm@egroups.com
> Subject: Re: [motm] CV Keyboards
>
> I'm working on mine. Pretty limited though.
> Analogue Systems has one that they're going to have available within a
> month
> or two, but expect it to be anywhere from 1500 to 2000.
>

Re: RE: [motm] CV Keyboards

2000-05-30 by ivancu@aol.com

In a message dated 05/30/2000 4:10:37 PM, noise@... writes:

<< Analogue Systems has one that they're going to have available within a
> month or two, but expect it to be anywhere from 1500 to 2000. >>

http://www.analoguesystems.co.uk/rssystems.htm

Interesting stuff. The control panel looks different than the panel to the
immediate left of the keyboard, which appears to have a joystick. Ridiculous
pricing though! Maybe they'll sell just the electronics without the keyboard
or enclosure.

Ivan

Re: [motm] CV Keyboards

2000-05-30 by J. Larry Hendry

OK, I have some comments on this.

1. I have a keyboard assembly that is brand new that was manufactured for
a MicroMoog that has the resistor assemblies already installed and ready to
go. I bought the thing for $25. No, I am not selling it. However, I can
tell you that the accuracy is not very good. I have compared my MicroMoog
CV output to the Kenton pro-2000 and the Kenton wins, hands down.

2. I don't see what the big deal would be to make a CV keyboard with each
note tunable. I think if I were doing it, I would use BOTH fixed and
variable resistance. As I see it (and please jump in there if you
disagree) the problem with fixed resistors is exact accuracy. The problem
with variable resistors is stability and cost. And, you would not want to
connect variable resistors so that tuning one, changes the total resistance
of the string.

So, I would make my voltage divider with the a fixed resistor and trimmer
in parallel. Then, this parallel combination would be connected in series
with as many as I needed for the number of keys I was planning (and maybe
trimmers on the ends for range). I would plan the voltage at the resistor
junctions to be about 1/2 way between the voltages I wanted on the keys so
that the wipers of the trimmers at 50% would be very close. Then each key
could be individually tuned without effecting the others. I think I would
make the trimmers multi-turn and of a higher value than the fixed
resistors.

What I haven't thought out yet is how the divider would connect to the keys
so that you could have a switch between lowest note or highest note
priority. Or how to make sure that two notes pressed at the same time
don't short out part of the divider network. I'll have to look at some
schematics.

Decent trimmers can be purchased in the ~$2 range. So, I don't see why it
has to be that expensive.

Stooge Larry (who is probably missing the obvious)


----------
Show quoted textHide quoted text
> From: ivancu@...
> To: motm@egroups.com
> Subject: [motm] CV Keyboards
> Date: Tuesday, May 30, 2000 11:10 AM
>
> I know this is somewhat silly, but is anyone out there still making a
> control-voltage keyboard? No, I don't want to use a MIDI keyboard with a

> MIDI-to-CV converter.
>
> Ivan
>
> ------------------------------------------------------------------------
> Find long lost high school friends:
> http://click.egroups.com/1/4056/5/_/529958/_/959703117/
> ------------------------------------------------------------------------
>
>

RE: [motm] CV Keyboards

2000-05-30 by Dave Bradley

Here's how Emu did it, as near as I can remember from foggy memory. No
resistor network. Keys activate a diode matrix which gets encoded into an
address, which feeds a DAC. Keyboard range is controlled by the gain into
the DAC. Glide circuit (posted on SynthFool) is added after the DAC. Low
note priority only.

Simple and stable!

You can't tune each note individually, but that should be an external module
anyway, like the Moog Scale Programmer.

Moe

Show quoted textHide quoted text
> -----Original Message-----
> From: J. Larry Hendry [mailto:jlarryh@...]
> Sent: Tuesday, May 30, 2000 4:39 PM
> To: motm@egroups.com
> Subject: Re: [motm] CV Keyboards
>
>
> OK, I have some comments on this.
>
> 1. I have a keyboard assembly that is brand new that was manufactured for
> a MicroMoog that has the resistor assemblies already installed
> and ready to
> go. I bought the thing for $25. No, I am not selling it. However, I can
> tell you that the accuracy is not very good. I have compared my MicroMoog
> CV output to the Kenton pro-2000 and the Kenton wins, hands down.
>
> 2. I don't see what the big deal would be to make a CV keyboard with each
> note tunable. I think if I were doing it, I would use BOTH fixed and
> variable resistance. As I see it (and please jump in there if you
> disagree) the problem with fixed resistors is exact accuracy. The problem
> with variable resistors is stability and cost. And, you would not want to
> connect variable resistors so that tuning one, changes the total
> resistance
> of the string.
>
> So, I would make my voltage divider with the a fixed resistor and trimmer
> in parallel. Then, this parallel combination would be connected in series
> with as many as I needed for the number of keys I was planning (and maybe
> trimmers on the ends for range). I would plan the voltage at the resistor
> junctions to be about 1/2 way between the voltages I wanted on the keys so
> that the wipers of the trimmers at 50% would be very close. Then each key
> could be individually tuned without effecting the others. I think I would
> make the trimmers multi-turn and of a higher value than the fixed
> resistors.
>
> What I haven't thought out yet is how the divider would connect
> to the keys
> so that you could have a switch between lowest note or highest note
> priority. Or how to make sure that two notes pressed at the same time
> don't short out part of the divider network. I'll have to look at some
> schematics.
>
> Decent trimmers can be purchased in the ~$2 range. So, I don't see why it
> has to be that expensive.
>
> Stooge Larry (who is probably missing the obvious)
>
>
> ----------
> > From: ivancu@...
> > To: motm@egroups.com
> > Subject: [motm] CV Keyboards
> > Date: Tuesday, May 30, 2000 11:10 AM
> >
> > I know this is somewhat silly, but is anyone out there still making a
> > control-voltage keyboard? No, I don't want to use a MIDI
> keyboard with a
>
> > MIDI-to-CV converter.
> >
> > Ivan
> >
> > ------------------------------------------------------------------------
> > Find long lost high school friends:
> > http://click.egroups.com/1/4056/5/_/529958/_/959703117/
> > ------------------------------------------------------------------------
> >
> >
>
> ------------------------------------------------------------------------
> Failed tests, classes skipped, forgotten locker combinations.
> Remember the good 'ol days
> http://click.egroups.com/1/4053/5/_/529958/_/959722281/
> ------------------------------------------------------------------------
>
>

Re: [motm] CV Keyboards

2000-05-30 by Paul Schreiber

Somewhere I have my design for a digital, monophonic keyboard. No CPU, about
$8 in parts +
the DAC. I used a 8-bit (BARF!) but today I'd use a 12-bit.

If I can find the plans, I'll give away free copies. It does work, I built
3-4 of these.

Has low-note priority, Gate and Trig outs.

Paul S.

Re: [motm] CV Keyboards

2000-05-30 by J. Larry Hendry

Sounds like a DAC is the way to go.
LH

----------
> From: Paul Schreiber <synth1@...>
> To: motm@egroups.com
> Subject: Re: [motm] CV Keyboards
> Date: Tuesday, May 30, 2000 5:26 PM
>
> Somewhere I have my design for a digital, monophonic keyboard. No CPU,
about
> $8 in parts +
> the DAC. I used a 8-bit (BARF!) but today I'd use a 12-bit.
>
> If I can find the plans, I'll give away free copies. It does work, I
built
Show quoted textHide quoted text
> 3-4 of these.
>
> Has low-note priority, Gate and Trig outs.
>
> Paul S.
>
>
>
> ------------------------------------------------------------------------
> Find long lost high school friends:
> http://click.egroups.com/1/4056/5/_/529958/_/959725334/
> ------------------------------------------------------------------------
>
>

Re: [motm] CV Keyboards

2000-05-30 by davevosh@aol.com

In a message dated 00-05-30 13:08:50 EDT, you write:

<< I don't believe it had a microprocessor, but I could be wrong. >>


dave,
if i remember correctly, the basic mono kybd didn`t have one. just a digital
"state machine" type circuit. the low octave gates feature always seemed
really neat and i could see plenty of uses for something like that.
best,
dave v.

Re: [motm] CV Keyboards

2000-05-30 by davevosh@aol.com

In a message dated 00-05-30 17:32:27 EDT, you write:

<< I'll have to look at some
schematics. >>



larry,
if you have them, there have been several different kybd interfaces published
in "electronotes". probably the interface ( regardless of how fancy one
might want to make theirs ) isn`t the problem, it`s a source of reasonably
priced kybd`s.
best,
dave

Re: [motm] CV Keyboards

2000-05-30 by Nathan Alan Hunsicker

I guess the next question is where would you find a keyboard assembly to hook up, I'm sure I could dissect one from an old broken d-5 somewhere, but is there any suppliers selling unassembled keyboard assemblies? -Nate

"J. Larry Hendry" wrote:

Sounds like a DAC is the way to go.
LH

----------
> From: Paul Schreiber <synth1@...>
> To: motm@egroups.com
> Subject: Re: [motm] CV Keyboards
> Date: Tuesday, May 30, 2000 5:26 PM
>
> Somewhere I have my design for a digital, monophonic keyboard. No CPU,
about
> $8 in parts +
> the DAC. I used a 8-bit (BARF!) but today I'd use a 12-bit.
>
> If I can find the plans, I'll give away free copies. It does work, I
built
> 3-4 of these.
>
> Has low-note priority, Gate and Trig outs.
>
> Paul S.
>
>
>
> ------------------------------------------------------------------------
> Find long lost high school friends:
> http://click.egroups.com/1/4056/5/_/529958/_/959725334/
> ------------------------------------------------------------------------
>
>

RE: [motm] CV Keyboards

2000-06-02 by Dave Bradley

Looks like I'll be needing those plans now, Paul!

Moe

Show quoted textHide quoted text
> -----Original Message-----
> From: Paul Schreiber [mailto:synth1@...]
> Sent: Tuesday, May 30, 2000 5:27 PM
> To: motm@egroups.com
> Subject: Re: [motm] CV Keyboards
>
>
> Somewhere I have my design for a digital, monophonic keyboard. No
> CPU, about
> $8 in parts +
> the DAC. I used a 8-bit (BARF!) but today I'd use a 12-bit.
>
> If I can find the plans, I'll give away free copies. It does work, I built
> 3-4 of these.
>
> Has low-note priority, Gate and Trig outs.
>
> Paul S.
>