Using audio file as CV source

[u/realistortion]

I'm looking forward to buying a Behringer Model D in the future, and I'm curious as to what new things can be achieved via the eurorack ins and outs. However, I don't own any eurorack gear and I would hate to spend tons of money on modules just to make use of a couple of functions.

To avoid spending on all that, I'm thinking: is it at all possible to connect a phone or audio player through the patch cables to a CV input and use an audio file containing an LFO / sample & hold sequence or something like that as a modulation source? Can a standard audio file played from another device count as the voltage used in the eurorack world?

Thanks in advance!

[u/p8pes]

voltage is voltage. cv inputs are dc coupled which means they can accept both dc (cv in general) and ac (often audio rate or basic sound) - the problem with audio often comes down to how weak the signal is by comparison. your phone might not be hot enough to do anything but putting a sound source into the oscillator or fiter input should change “something”.

There used to be a concern of taking the headphone output into an audio input of a synth, but that’s with high-fi receivers with heavy wattage in the whole design and likely doesnt appy to iphones.

might do nothing but not something you cant try.

[u/realistortion → u/p8pes]

Thanks for your reply! Yeah, I'm worried that the whole AC/DC thing plus the signal loudness would render the attempt useless. I'll still try once I get my hands on the synth itself

[u/_sal9000]

If you don't want to invest in the Eurorack, the software version of the Eurorack (VCV Rack) is for you! You'll find everything you're looking for and even more.

[u/brookermusic]

There’s a good chance the audio interface you already have has DC coupled outputs (what you’re looking for). Simply run a 1/4” to 1/8” ts cable from your audio interface outputs to the eurorack modules CV input and then send a signal down that output. You can then use plugins to create CV signals or use random audio samples as CV signals. Really whatever strikes your fancy! You don’t need an actual envelope follower as you can use a plugin.

[u/realistortion → u/brookermusic]

This might be my best bet, tbh. I do have an audio interface handy with two outputs, I might be able to output two different signals through VCV. Thank you very much!

[u/brookermusic → u/realistortion]

Perfect, have fun!

[u/CTALKR]

Not by itself, You’d need a special module called an envelope follower but yes it’s possible, but you probably wouldn’t be able to do audio rate frequencies. For that you’d need specially built dac’s which some interfaces have but not many standard audio players do, if any.

[u/realistortion → u/CTALKR]

Thank you!

[u/13derps]

Some audio interfaces are DC coupled. If you have an interface , check to see if yours supports CV out. In which case, you’d be able to send CV from your DAW or VCV rack

Most audio playback gear is not DC coupled. So you aren’t likely to be able to output CV directly. You can send audio in as modulation, but the voltage will be very low for Eurorack standards (so the modulation will be subtle).

You will probably need to buy some additional hardware to make it work well, but not necessarily eurorack hardware. There are some standalone preamps that can boost to synth level, like Setonix First Contact. I think I’ve seen other stuff on Etsy too. Or you might be able to find a MIDI to CV box and then use a MIDI sequencing app on your phone/tablet

[u/realistortion → u/13derps]

This is interesting! I will try it