At what sample rate should I record my field recordings ?

[Wanterkeelt]

Hi,
first of all a happy new year to all you Ambient Onliners :thumbsup:.

My question(s): I have a mobile field recorder capable of recording up to 192khz/24 bit. So far I've recorded everything at 44.1khz/24bit. But I recently read that if you record at higher sample rate, you'll have better results / less artifacts when you do time stretchs, tempo changes, pitch shifts, etc.

So would I benefit from recording my field recordings at 88,2khz / 176,4 khz (hard disk space is not a problem) ? Did anyone try that ? And what were your results ?

I made a first try and found out that you'll also have to work in a higher sample rate in your DAW (in my case Reaper), otherwise it simply resamples the WAV file when you import it, and I guess that would make you lose all the benefits.

I'd be grateful for your experiences in this domain.

[Organic Patterns]

I'm not any expert, but I am studying sound design, so my experience is based on what I've been told by my teacher.

If you're interested in sound design, then use as high a sample rate as possible. It will allow you to transpose the audio much further down, whilst still maintaining the high frequencies. This is because a lot of the audio material, which you can't hear, since it's in a non audible frequency range, will be brought down to an audible range, when transposed down. This is pretty cool since you will discover artifacts you're not used to hearing, which can be useful for some interesting sound design.

When time stretching, your audio will also stay much more smooth compared to a lower sample rate. Look at it this way, if you have two lines, one for 44.1 kHz and one for say 96 kHz, each line has a specific amount of dots(samples) based on the sample rate - the higher a sample rate the more dots. If you stretch out these two lines, the 96 kHz will have more dots and therefore there will be less space between each dot, whereas the 44.1 kHz line will have less dots and further between them. More information in your audio will allow you to time stretch it further without pulling out the nasty artifacts, your result will therefore be much smoother.

As for the sample rate in relation to the sample rate in your DAW - make a new project with a sample rate equivalent to the sample rate for your audio, process and bounce the sound and insert it in your 44.1 kHz project where you make the music. However, it is worth mentioning that, some plugins resamples the inserted audio up to 96 kHz and then resamples it down to the sample rate for your DAW when outputting the sound. So by using plugins to process the audio you may solve the issue, depending on which plugin you've used.

[Wanterkeelt]

Thanks for this very competent post.

[warrendaly]

One of the more important settings to consider is the bit depth, 24bit or 32bit is superior to 16bit. You'll be able to process files and remove noise floor (if that's what you wish to do) much easier.
I always record with 24bit.

I do not believe the previous post is technically correct "non audible frequency range, will be brought down to an audible range" but I'm happy to learn more if I am incorrect.
in fact, the microphones are capturing the audio range from 30hz to 22Khz (check your recording gear specs) so you could have a sample rate of 192Khz or if your hardware was able to sample 1Mhz....the microphone is only capturing audio from 30hz to 22Khz.... (In it's simplest explanation; once the sample rate is above Nyquist the sample rate does effect the range of frequencies that are captured)

I record using 44khz/24bit or sometimes if I require 48khz samples for a movie (sound files for video are 48khz) I'll record using 48Khz/24bit. There are discussions suggestion not to record at 48Khz if you require the samples for a 44Khz production as resampling from 48khz down to 44Khz can introduce conversion noise.

There are reasons to use 96Khz.. but I don't currently require those benefits and I know that I can hear aliasing when my DAW resamples down.

As Wanterkeelt correctly pointed out, and the only time I have found that sampling at 192khz is of any use other than taking up vast amount of disk drive space, is for stretching. But if you're using PaulStretch, I believe this will only handle 16bit WAV files.

Please read this http://www.soundonsound.com/sound-advice/q-should-i-use-high-sample-rates

Happy recording.


Most DAWs (certainly ableton) the channel strips are 32bit floats, so there might be some use for me to change to 44Khz/32bit ... I will investigate.

[Guest]

"I do not believe the previous post is technically correct "non audible frequency range, will be brought down to an audible range" but I'm happy to learn more if I am incorrect.
in fact, the microphones are capturing the audio range from 30hz to 22Khz (check your recording gear specs) so you could have a sample rate of 192Khz or if your hardware was able to sample 1Mhz....the microphone is only capturing audio from 30hz to 22Khz.... (In it's simplest explanation; once the sample rate is above Nyquist the sample rate does effect the range of frequencies that are captured)"

This is probably not correct - certainly mics can capture way above 20KHz and if the sample rate is above 44K then they will be capturing higher frequencies which can be transposed down into the listenable range merely by playing back the higher sample rate at a lower rate. ie play back 96KHz signal at 48Khz. There is a pretty strong roll off in both power of high frequencies in the actual world (mostly) and in the ability of the mics to capture those frequencies unless specially designed to do so. But for field recording I would always recommend 96KHz. You will probably capture useful information.
For hydrophones a higher rate is particularly important as lots of underwater beasties make high frequency sounds (and at really high power!)

[seismic1]

"
For hydrophones a higher rate is particularly important as lots of underwater beasties make high frequency sounds (and at really high power!)

Not in my line of work

[Guest]

"
For hydrophones a higher rate is particularly important as lots of underwater beasties make high frequency sounds (and at really high power!)

Not in my line of work

I bet you are loud though ;)

[warrendaly]

In fairness,Wanterkeelt
asked about a 'mobile field recorder' I was wrong and made huge presumptions that he was using a Zoom (H2n or H4n) or similar and was using the inbuilt microphones (30hz to 22khz approx).

But he might be using Earthworks kit... I'd have to save up for a while as they're $999, and some of the other models that operate up to 40khz are $2,499++

https://www.sweetwater.com/store/detail/SR40

I've recently completed some DIY Binaural mic builds... working on a Jecklin Disk at the moment. http://www.sengpielaudio.com/JecklinDisk.pdf

[Guest]

In fairness,Wanterkeelt
asked about a 'mobile field recorder' I was wrong and made huge presumptions that he was using a Zoom (H2n or H4n) or similar and was using the inbuilt microphones (30hz to 22khz approx).

But he might be using Earthworks kit... I'd have to save up for a while as they're $999, and some of the other models that operate up to 40khz are $2,499++

https://www.sweetwater.com/store/detail/SR40

I've recently completed some DIY Binaural mic builds... working on a Jecklin Disk at the moment. http://www.sengpielaudio.com/JecklinDisk.pdf

low cost ultrasonic mic http://www.wildlife-sound.org/equipm...ltrasonic.html

and a high cost one

https://en-us.sennheiser.com/condenser-microphone-recording-soloists-mkh-8050