Deriving 48 Khz recordings from 96 Khz ones

[Peter Roos]

(copy from my post at NoiseVault)

Next week I am going to sample a good hardware box. My intention is to sample it at least at 44.1 Khz and 48 Khz rates (24 bit).

However, I would also like to get back to this machine to re-sample it entirely at 96 Khz and to create a good collection of surround reverbs as well.

I am now first starting with true stereo and mono-to-stereo recordings (thus 3 stereo impulse files per program).

My question now is: will there be ANY audible difference between recorded 48 Khz impulses and downsampled ones (from 96 Khz recordings?). If not, I can better record directly at 44.1 and 96 Khz (saving me at least 1/3 of my recording session time).

Has anyone ever experimented with this?

I don't want to try this with the uneven division from 96 to 44.1, neither do I want to record at 88.2 Khz (because IMO nobody seriously works with that sample rate).

As for a set of "light" 16 bit versions: I guess I should just dither down my 32 bit working material to 16 bit. I see no point in setting all equipment to 16 bit and then re-record everything again, just to create a set of "light" versions of the "real" 24 bit impulses. Or am I wrong here?

Thanks for any (early) reflections [;)]

Peter
www.PeterRoos.com / www.Samplicity.com

[mathis]

I think the answer to the 16bit versions is clear and the one you suggest.

About Sample Rate conversion you can read something completely different every day. And everybody and their brother made their tests and everybody hears something different. So should really try yourself to be confident.

As far as I understood a recent discussion it curiously makes no difference for the math of the algorithm if you convert to a number which has a 'simple' relation, like half rate.

[Dietz]

You _could_ sample in 96 kHz and resample the IRs to 48 (and even 44.1) later, using a _good_ resampler (Voxengo comes to mind). If you are talking about reverb, OTOH, there's actually no need to go for frequencies that high, as most real rooms have a distinctive roll-off much earlier than 20 kHz.

No doubt about 24 bit recording, though.

/Dietz - Vienna Symphonic Library

[Peter Roos]

Thanks,

Yes, for sonic reasons I also see absolutely no advantage in using 96 and 88.2. However, this will probably be a commercial project and you know how demanding customers can be when it comes to "specs". [;)]

Personally I only think 44.1 and 48 Khz are must-haves.

Peter

[Dietz]

I don't know what you're heading for, but during the reasearch for the upcoming MIR-engine all the involved Golden Ears couldn't tell a significant difference between 48 and 96 kHz-IRs. So - we record at 96/24 (to 32-bit files), but will most likely be processing at 48 kHz (the reverb, not the direct signal, of course).

/Dietz

[mike harper]

[6]

hmm speaking of any more info it is namm you know!

[Dietz]

I know it's NAMM, but it's not the time for more info yet :-]

/Dietz