recording cv to tape

[ocp]

Does anyone know what kind of recorder I should use to record controlled voltages to tape?

 

[Jörg]

Hmmmm wouldn´t the voltages of tape line level be too small for that?
http://en.wikipedia.org/wiki/Line-level

 

[ocp]

Yes. I've tried it with a 4 track k7 recorder some time ago.
However, I know it is possible with the right equipment.
I read Morton Subotnick and others have done it and was curious about it.

 

[Jörg]

Perhaps you would need a recorder that is able to handle +/- 5V?
If such a thing exists.

Anyway, it´s a cool idea!

 

[comboy]

or you need some kind of amp

cv -> tape reduce the amplitude of the signal to tape level
tape -> cv amplify the voltage by the same factor like you reduced before

should work, but i think it will add some noise to the cv

so long,
julian

 

[Jörg]

Yes, but do you think a "normal" VCA will be sufficient for this?
A nice field for some research.

 

[Anonymous]

Control Voltages start from DC (0Hz), a tape recoder starts at some 10Hz.
Professional recoders for measurement purpose use FM to record such signals.
So without some sort of transformation it is not possible to record CVs on Tape.

 

[ocp]

SOS (Sound on Sound) Technical Editor Hugh Robjohns just answered my post.
He says a data logging recorder would do the trick.
I googled and found this: http://www.dataq.com/products/startkit/di194rs.htm

 

[haesslich]

seems to be a datalogger for pc.
these are used to measure and log (electronic) data on a computer. and i guess that the 10bit ADC may not be sufficient for real modular specialists though i think that measuring equipment usualle must be very precise.
you need something that logs data on tape?

 

[Anonymous]

When I read 'data logger' Teac comes in my mind... ( http://www.teac.com/drindex.html ) ... they will do fine, but maybe they are a little pricey.

The Dateq box is just a recorder - no playback. It collects 240 samples/second which is about one sample every 4 millisecond.

 

[Ilanode]

Never have given it a try but the following should work without any special tape:
Feed the CV in question into the VC In of a VCA, an audio signal into the audio in. Record the result on any tape. Play it back through an Envelope Follower to extract the envelope (= original CV). This should work with an average modular synth at least. Even though it probably won't do the job to controll the pitch of a VCO.

 

[Moogulator]

you CAN do this, but you def'ly need a converter (since audio is not loud enough), but I doubt it will be exact enough..?

 

[Ilanode]

you CAN do this, but you def'ly need a converter (since audio is not loud enough), but I doubt it will be exact enough..?

Proably my outlay was kind of unclear: A tape has an pre-amp (= rec. level) while the audio out of the tape is too low for a synth you're going to raise the output to the level needed by using the Env. Follower. At least any of those I'm familiar with could do this. However, I agree it will be not exact enough for a tonal pitch control. Nevertheless it should work for unpretencious VC for VCFs and VCAs. For atonal music/noise it might be still an intersting way to go anyway.

 

[ocp]

I used a minidisc to record the output of a LFO and it works. However, the CV value is not precise.
I'll keep experimenting...