OT: 12 bit versus 16 bit?

Randy Brown wrote on 4/5/2003, 5:18 PM

I have been recording musical performances in 16 bit stereo (and sometimes 24 bit multi-track if I lug my PC rig along; a real pain). I'm about to get a second Canon XL1S that would give me the option to have 8 tracks of 12 bit using both cams (if I buy another 4 channel XLR adaptor) but don't want a noticeable degradation in quality (final product burned to VHS and DVD). I feel sure some of you have A/B compared and would very much appreciate your opinion.
TIA,
Randy

Comments

Tyler.Durden wrote on 4/5/2003, 5:56 PM

I cannot hear the difference between 12 and 16.

HTH, MPH

jetdv wrote on 4/5/2003, 8:47 PM

You will need Scenalyzer Live or some other program that will capture 4 channel audio. The Vegas capture program won't.

Spot|DSE wrote on 4/5/2003, 9:11 PM

The place you'll REALLY hear the difference is if you are using processing or fades, or audio with high transients. I promise, Marty, you'll hear a difference if it's more than just spoken word. If it's only spoken word, and doesn't have a lot of dynamics, and isn't being faded out, you'll hear it. Otherwise....it's a personal pref. 4 channels are great, if it's just spoken word in a relatively quiet room. Start recording music, high transients, traffic, water, and you'll hear the diff.

Randy Brown wrote on 4/6/2003, 9:33 AM

Thanks guys,
I would most likely only need it for multi-tracking live music (to enable re-mixing in post). My ears can't tell a big difference in 24 bit and 16 bit (when comparing with Event 2020's) ; if it's the same comparison proportionately (especially through TV speakers) between 16 bit and 12 bit, it would be worth it for me to go with 12 bit and not tote my PC rig along (full size PC with mixing board, Delta 1010 etc). From what I've read about DSE, his ears could probably tell the difference in 1 bit but I'm wondering about the average person. I suppose I could give the musicians the option to pay more for the PC set-up...hey if I get enough of them choosing 24 bit maybe I could just buy a laptop!
Thanks again guys,
Randy

VOGuy wrote on 4/6/2003, 6:02 PM

Hi Randy,

Here's one way to look at it: Each time the signal's volume is reduced 6dB, it the sound system uses one less bit to reproduce the waveform. This means that the quieter an original recording, the less resolution is achieved. This is the inverse of most analog recording systems, where you get less distortion (at the expense of more background noise) as the signal gets quieter.

As you mix the tracks together, with each doubling of the number of tracks, you are adding one to the total number of bits used. (Assuming that the 12-bit tracks haven't been "boosted" back to 16-bit levels). If you take two tracks, and mix them together, doubling the audio volume, you are taking one additional bit to reproduce the waveform. Four tracks - two additional bits, and with eight - three additional bits.

So, it could be argued that when you do your final mix, that you are really using 15 bit audio, except that you will probably mix to stereo, bringng the total back to 14-bits. However, since most people record at -12 db (which only uses 14 bits, most of the time) you are actually loosing nothing, if you record at maximum volume, being very careful not to distort, you will be back to the equivalent of 16 bits.

Of course this is all theoretical, and may be totally useless when applied to the real world.

(Whew!)

Let us know how it works.

Travis
Travis Voice Services
www.Narrate.biz

--