Anyone have experience with recording ultrasonic sound? I’d be interested in this for sampling and repitching the sounds to be audible and then process.
Nyquist-Shannon theorem says you cannot encode or produce a sound whose frequency is above F/2, F being in our case the frequency at which you play the sample (or at least that’s what I remember).
For Digitakt, it’s 48 kHz, so highest note you can play is 24 kHz.
Maximum audible frequency is 20 kHz, so your ultrasonic range is rather limited…
Note : you may pitch up the signal with a system that can play to a higher frequency.
DT wouldn’t know it was a 384 kHz sample though, so it’d just reveal unheard sample content 3 or 4 octaves higher than we’re used to if there’s interesting stuff there - surely there is, great idea !
Sorry i wasn’t clearer there LyingDalai – i would repitch to an audible range and process the sound – the Digitakt is just for the playback – i was also just having some fun mentioning the Digitakt.
Also excellent point avantronica, so i wouldn’t even have to process the ultrasound.
I guess i could use the Ultrasonic-Digitakt from Elektron – but my ears aren’t quite what they used to be.
But that does bring up another point – i noticed that a couple of the companies i listed also make devices for reproducing the ultrasonic sounds. EDM for bats and dogs!
So with Nyquist the 384 kHz sample only goes to 192 kHz.
Edit (after 3♥️)
I liked this project as the guy used equipment for seismic activity and attached it to walls/pipes etc in an old abandoned cement silo on the Chinese/Russian border.
At one point I can hear dogs, but forgot where!
So much detail it’s almost caused me a few mental breakdowns
if you sample in the ultrasound domain, you are better off doing the repitch in Matlab or Python Scipy, i dont think digitakt’s -24 semitones will cut it (:
I’ve been exploring the world of EM a bit with the tiny EM mics from LOM, and they’ve made some very beautiful super sensitive tiny capsule electret mics too, which make me feel like I’m a bat.
Ultrasonic is very interesting! I want to be a cyborg.
I’ve long believed there are far more amazing things we can’t hear/see.
I fancied the Koma field kit stuff for a long time but decided against it as I have other stuff to explore…
Interested in Soma labs and their talk of this Ether machine in the works but I think it’s for electromagnetics only but I’m sure it will have a crazy Russian slant on it! Time will tell.
Yes, those ones I record into a PCM-D50. It is acceptably awesome. Now I am listening to the field recordings of Izabela Dłużyk (https://zvukolom.bandcamp.com/album/soundscapes-of-spring) also on LOM. And planning a trip to the forest where that album was recorded.
As Jamie points out another use for recording above 20 KHz is that you will hear a more realistic sound when you shift a sound down pitch. He pitched down the crunching of table salt, as for instance.
Another thing cool about the Sound Devices audio recorder interface beyond its frequency range is that it records in 32 bit floating point format which gives a very large dynamic range and more protection from digital clipping.
So these together could make an audio quality option that would go moderately high into ultrasonics.
I record into a PCM-D50. It is acceptably awesome. Now I am listening to the field recordings of Izabela Dłużyk (