cebec

Can someone shed some light on high-resolution interfaces between Max/MSP and analog control voltages?

Phil Rees and Kenton have a 16 bit DAC-based converter, I see...

high-res-interface-between-maxmsp-and-analog-cv

The Miditron can handle analogue in with a range of 0-16383 using Pitch 

The Miditron can handle analogue in with a range of 0-16383 using Pitch 
bend.
See www.eroktronix.com.

The MidiTron automatically gives 10-bit resolution when you set the 

message mode to pitch bend for an analog terminal. You can have up to 

ten 10-bit analog ins by using pitch bend on 10 different MIDI 

********************************************

* MidiTron MIDI to Real World Interface *

The MidiTron automatically gives 10-bit resolution when you set the 
message mode to pitch bend for an analog terminal. You can have up to 
ten 10-bit analog ins by using pitch bend on 10 different MIDI 
channels.

********************************************
* MidiTron MIDI to Real World Interface    *
* Now available from http://eroktronix.com *
* Only $149                                *
********************************************


Isn't the original poster looking for something that works the other 

way around, i.e. provides high-res analog *output*?

PWM is a cheap alternative to generate quasi-analog outputs w/o the 

need for a DAC. It works very well to control motors and lights. The 

MidiTron provides PWM (up tp 20?), as does my gluion interface (up to 

However, I've never tried to control an analog synth with it. For 

starters the frequency at which the PWM operates would have to be above 

20kHz. The gluion can do this, however at a reduced resolution of 

10bits. Maybe this could be optimized to some extent by carefully 

selecting integrating capacitors, although this depends a bit on the 

In any case I haven't tested this, so I'd be reluctant to sell you a 

unit based on speculation. I hope I can get hands on an analog synth 

soon to give it a try - if you know someone in Berlin who'd like to 

Isn't the original poster looking for something that works the other 
way around, i.e. provides high-res analog *output*?

PWM is a cheap alternative to generate quasi-analog outputs w/o the 
need for a DAC. It works very well to control motors and lights. The 
MidiTron provides PWM (up tp 20?), as does my gluion interface (up to 
66).
However, I've never tried to control an analog synth with it. For 
starters the frequency at which the PWM operates would have to be above 
20kHz. The gluion can do this, however at a reduced resolution of 
10bits. Maybe this could be optimized to some extent by carefully 
selecting integrating capacitors, although this depends a bit on the 
desired update rate.
In any case I haven't tested this, so I'd be reluctant to sell you a 
unit based on speculation. I hope I can get hands on an analog synth 
soon to give it a try - if you know someone in Berlin who'd like to 
bring one to my lab let me know....

P.S. just found this: http://www.doepfer.de/mcv24.htm
probably way easier.....


that's right. i'm looking for the highest-resolution way to control an analog synth with max/msp.

that's right. i'm looking for the highest-resolution way to control an analog synth with max/msp.
thanks for all the replies so far!


Oops, yes it appears so. MidiTron does up to 20 PWM outputs with up 

to 7 bits resolution, though the rate goes down with more outputs 

enabled (there is a chart in the manual downloadable from 

Not sure of your application, but you might consider audio outputs to 

be hi-res D/A sources which can be driven directly from MSP.

Oops, yes it appears so. MidiTron does up to 20 PWM outputs with up 
to 7 bits resolution, though the rate goes down with more outputs 
enabled (there is a chart in the manual downloadable from 
http://miditron.com).

Not sure of your application, but you might consider audio outputs to 
be hi-res D/A sources which can be driven directly from MSP.

> Can someone shed some light on high-resolution (higher than MIDI or 

> 7 bits) interfaces between Max/MSP and analog control voltages?

> Is there anything like this? Are there 14 bit MIDI to CV converters?

it has been reproted on this list that a Motu 828 has DC coupled outputs

so you could go from MSP to analog out. I have no info about the

On Jan 12, 2006, at 7:32 AM, Pierre Alexandre Tremblay wrote:

> Probably less interesting than the new macs, but less speculating 

> I remembered someone talking about generating Control Voltage out 

> of Max by regular audio converters, and people had ideas on some 

http://www.synthesisters.com/hypermail/max-msp/Dec04/19244.h

> Since the thread ends abruptly without anyone actually giving a 

> reliable answer, I went down with a motu 828 mk1 and mk2 and 

> plugged them in an oscilloscope. I also tried the Powerbook output.

> Both the motu output DC without problem, at the same voltage than a 

> 440 cycle. The mk2 has a real +/- 5v, and the mk1 has +/- 3.2 v.

> The mac output does have an HPF, therefore is losing a lot of 

> I thought it could be helpful to someone else.

>
> Can someone shed some light on high-resolution (higher than MIDI or  
> 7 bits) interfaces between Max/MSP and analog control voltages?
> Is there anything like this?  Are there 14 bit MIDI to CV converters?
>

it has been reproted on this list that a Motu 828 has DC coupled outputs
so you could go from MSP to analog out. I have no info about the
resolution (number of bits).

> Hi list !
>
> Probably less interesting than the new macs, but less speculating  
> as well!
>
> I remembered someone talking about generating Control Voltage out  
> of Max by regular audio converters, and people had ideas on some  
> machine who would do it and some not.
>
>  http://www.synthesisters.com/hypermail/max-msp/Dec04/19244.h tml
>
> Since the thread ends abruptly without anyone actually giving a  
> reliable answer, I went down with a motu 828 mk1 and mk2 and  
> plugged them in an oscilloscope.  I also tried the Powerbook output.
>
> So here are the result:
>
> Both the motu output DC without problem, at the same voltage than a  
> 440 cycle.  The mk2 has a real +/- 5v, and the mk1 has +/- 3.2 v.
>
> The mac output does have an HPF, therefore is losing a lot of  
> voltage from 10Hz and lower.
>
> I thought it could be helpful to someone else.
>
> pa
>


ah, that's very helpful. i'll check my E-MU 1616m to see if it's outputs are DC coupled.

but only four outputs are 12bits, rest is 8bit...

-------------------------------------------

"The mystery of the world is the visible, not the invisible"

perhaps,
but only four outputs are 12bits, rest is 8bit...
and you're stuck with midirate updates..

                         Joost Rekveld
-----------    http://www.lumen.nu/rekveld

"The mystery of the world is the visible, not the invisible"
(Oscar Wilde)

-------------------------------------------


How many channels do you need and how many have to be high-res?

Usually you only need high-res for pitch control, while other 

parameters work fine with less resolution.

The Doepfer box I suggested has a nice mix of 4 high-res + 20 low-res.

How many channels do you need and how many have to be high-res?
Usually you only need high-res for pitch control, while other 
parameters work fine with less resolution.
The Doepfer box I suggested has a nice mix of 4 high-res + 20 low-res.

i'd like as many hi-res as possible but the doepfer looks good.

essentially i'd like a very high-res interface between my PC and my analog modular.

i'd like as many hi-res as possible but the doepfer looks good.
essentially i'd like a very high-res interface between my PC and my analog modular.


In my experience, the problem using the 828 to generate CV has been a loss of linearity caused by impedence mis-matching. Making a very simple voltage following buffer with a cheap opamp for each output (or input) channel of your 828 should let you send sig~ out of your 828 with linear response.

In my experience, the problem using the 828 to generate CV has been a loss of linearity caused by impedence mis-matching.  Making a very simple voltage following buffer with a cheap opamp for each output (or input) channel of your 828 should let you send sig~ out of your 828 with linear response.  

Quote: cebec wrote on Tue, 28 February 2006 14:53

----------------------------------------------------

> i'd like as many hi-res as possible but the doepfer looks good.

> essentially i'd like a very high-res interface between my PC and my analog modular.

i can recommend doepfer as a great company. if you have any questions, subscribe yourself to the doepfer A100 yahoo list.

dieter is up there himself and answers many questions, some other very knowledgeable people up there too, though I wouldn't expect them to have a lot of experience with max, but that doesn't seem necessary.

Quote: cebec wrote on Tue, 28 February 2006 14:53
----------------------------------------------------
> i'd like as many hi-res as possible but the doepfer looks good.
> essentially i'd like a very high-res interface between my PC and my analog modular.
>
----------------------------------------------------

i can recommend doepfer as a great company. if you have any questions, subscribe yourself to the doepfer A100 yahoo list.
dieter is up there himself and answers many questions, some other very knowledgeable people up there too, though I wouldn't expect them to have a lot of experience with max, but that doesn't seem necessary.


high-res interface between Max/MSP and analog CV