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Vertige
05-12-2002, 05:18 PM
I have a question. I need to record source at mic level ( and keep it that way ) for a back-up system on a show i work for. My question is which bit depth should i use, i heard that a lower bit depth for low level was better then a higher one....

Thanks

sdevino
05-12-2002, 07:41 PM
there was a 300 plus message thread on a similar topic a while ago. I hope we do not restart that here.

But here is my advice. Higher number of bits gives you the ability to capture finer musical detail no matter how weak or strong the signal is. If you want to preserve detail use higher bit depth.

In fact in your situation if you really mean to somehow record mic level without any gain, you will get 256X more signal to noise twith 24 bit than with 16 bit, so recording a very weak signal should always be done with the highest bit depth possible.

tom_mac
05-13-2002, 07:04 AM
he's right!

SoundWrangler
05-13-2002, 02:47 PM
Absolutely, preferable to record at higher bit-depth ESPEC. if at low levels (& keeping in mind that acoustically "live" spaces also have much very low-level info as reverberation decays to silence - even if principal sound source is plenty loud). If you're recording a long show, though - let's not forget to note that file sizes/disk space required will be approx. 50% greater at 24 vs. 16 bits.

Nika
05-14-2002, 10:02 AM
Can't agree, guys.

Higher recording levels (or higher bit depth) only give you the ability to record higher dynamic range. I think that Steve may have meant the same thing. Higher bit depth only gives you more "detail" in that it preserves more dynamic range. If your signal is low level to start with then it's very likely that the dynamic range of it is low (or shall we stipulate - the "audible" dynamic range of it is low) so recording hotter or lower (or more or less bits) won't likely affect the signal quality of your recording much at all.

We've been eating this subject up over here if you're interested:

http://www.prosoundweb.com/recpit/viewtopic.php?t=1359

It's not as long as the thread that transpired here earlier, but the reading is just as, or even more intense.

Nika.

sdevino
05-14-2002, 02:16 PM
My point was that if he is recording a weak signal he might as well get the best signal to noise possible.

Remember this application is sending mic signal to HD with no gain. So assuming the signal level manages to be above the noise floor of the system, and the system noise is lower than the 16 bit noise floor, 24 bits will let him get at least to the noise floor of the system.