[LAU] master levels

[Fons Adriaensen]

On Mon, Feb 02, 2015 at 02:41:44PM +0000, Harry van Haaren wrote:
 
> In short: mix with enough headroom in Ardour, ensure that the
> master-output level in Ardour is happy - ideally somewhere between -20
> and -6dB. When that signal arrives at the DAC, it will not
> significantly impact on SNR. Then use an analog volume fader to change
> the speaker-volume.

Right.

Signal to quantisation noise ratios are not a concern in
most cases even with 16 bits - other factors will dominate
the result. Some numbers to think about:

16 bits gives you a dynamic range of more than 97 dB, that
is unweighted and without dithering. Assume your average
RMS level is 15 dB below maximum, and that the listener
will adjust her volume to 95 dB SPL (that is quite loud).
Quantisation noise will be at 12 dB SPL. That is below
the ambient noise level in most places. With dithering
on the final 16-bit result it will even be better.

Second example: You're recording an artist who produces
80 dB(A) SPL, and the self-noise of your mic is 12 dB(A),
a typical value for a good quality studio condenser mic.
Then the S/N ratio of the recording can't be better than
68 dB, the equivalent of around 11 bits.

Ciao,

-- 
FA

A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)