[sdiy] DACs on-board 12 vs external 16 vs 24 bit

[Tom Wiltshire]

On 6 Nov 2013, at 11:03, cheater00 . <cheater00 at gmail.com> wrote:

> On Wed, Nov 6, 2013 at 11:44 AM, Tom Wiltshire <tom at electricdruid.net> wrote:
>> The average human isn't going to hear much, if any, difference between 12, 16 and 24 bit DACs if the sample rate is reasonably high.
> 
> I would only be happy to make such a statement in the case of an
> oscillator signal, which due to its very correlated power is going to
> do funny things to our auditory system.

That's the situation we're talking about, and the situation I made the statement about!

Justin's case was specifically an oscillator, and he didn't even mention wanting level control done digitally, so I assumed we'd be using the full bit depth/SN ratio and outputting signals at full volume. Similarly, I assumed that we've got one DAC outputting one signal - this is a long way from sending a full mix of many instruments through one DAC. I wasn't recommending using a 12-bit DAC for mastering your DAW or anything like it!

> On Wed, Nov 6, 2013 at 11:59 AM, Richie Burnett
> <rburnett at richieburnett.co.uk> wrote:
>> save 24-bit for something like a synth that has to output 32 voices, each made of 4 oscillators all mixed together, with envelopes etc. The extra quantization levels are really useful here!
> 
> I seriously doubt 24-bit D-A is within the reach of any synth
> designer. Or even 22-bit. Not even Yamaha would bother.

The DAC chips to do it are easily and cheaply available. Whether the analog side lives up to the promises made by that incredible S/N is a different story. But Richie is right - at least if you've got that much resolution, you can add a load of waveforms together without having to lose bits off the bottom, even if some of that might get lost in the noise floor.

T.