Ultrasonic Sound Sampling

The Lounge General Discussion
#1

I’m interested in sampling ultrasonic sounds.

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.

I did find some ultrasonic microphone makers:

Dodotronic – Ultramic Ultrasonic USB Microphones

Pettersson Eletronik – Ultrasound Microphones

Avisoft Bioacoustics – Ultrasound Microphones

The Dodotronic is quite affordable.
Being able to pair these with a tablet or a smartphone is good too.

If a 96 kHz sample rate isn’t enough – there is always 384 kHz for your Digitakt.

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#2

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.

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#3

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 !

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#4

Oh, I hadn’t read the OP correctly, sorry.
Very interesting!

#5

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.

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#6

I’m a bit tired, tonight…
I really like the idea of hearing bat shouts, or all the sounds we’re deaf to… Tell us more if you dig deeper !

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#7

532358df4816dfacea7a33d972902357

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#8

This last one is ready to sample. Snare! There’s also something good to the rhythm too.
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#9

Geophones…

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 :exploding_head:

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#10

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 (:

#11

i also want to note that whatever you record to, it CANNOT hit a software ADC (analog to digital converter).

this is because (again, result of nyquist), your ADC often has a lowpass filter implementation in the circuit.

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#12

Nice low ambient sound totallyruined. Related to this there’s also this from the last couple of days, recording of the Antarctic Ross Ice Shelf and the wind on ice.

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#13

Awesome topic, I’m following closely!

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.

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#14

Nice!
Sounds almost 8bit…

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.

#15

You mean like this?


Uši Pro microphones for delicate sounds.

Actually i think there might well be some ultrasounds here with all these sounds too.

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#16

Yes, those ones :slight_smile: 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.

#17

A new Geophone from LOM.
“Geofón is a sensitive Geophone adjusted for field recording purposes”

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#18

Sold out within an hour of the email D:

I have to wait for the next batch. LOM make such beautiful audio things.

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#19

In the latest Sonic Talk 670 Jamie Lidell talks about a 100 KHz microphone and digital microphone interface.

Sanken CO-100K

Sound Devices MixPre II

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.

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Zoom F2 Field Recorder (32-Bit Float Recording)
#20

That that sanken is a little pricey…
Lidell does some cool stuff with it on the latest HOWA though.

The crumbling maldon sea salt is particularly pleasing.

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