[linux-audio-user] Linux music editor, greater than 32-bit ?

[Tim Orford]

On Thu, Feb 22, 2007 at 04:04:34PM -0500, Paul Davis wrote:
> On Thu, 2007-02-22 at 15:53 -0500, Rick Wright wrote:
> 
> > This is true, but as Folderol wrote, 32 bits should be *plenty* of 
> > dynamic range for audio.  In fact, it has been argued that ~22bits is 
> > sufficient as beyond this you get into the h/w noise floor, hearing 
> > limits, etc.
> 
> 32 bits of resolution gets you close to the *thermal* noise floor. i.e.
> your recording contains noise contained by brownian motion. not very
> useful.

Unfortunately digital processing has completely different set of
problems than analogue.

32 bit seems to be plenty for us mere mortals with more practical 
problems, but I wouldnt dismiss the esoteric benefits of increased 
resolution for complicated processing tasks so easily when quality 
is the prime concern. The maths is very tricky.

Some nice products do use 64 bits (or other high resolution integer 
formats), and I'm not so convinced that their nice sound is
completely unrelated to the sample size.

As an interesting, though slightly obsure example, this article claims 
that 32bit float is not enough to make a dithered 24bit integer signal:
http://www.cadenzarecording.com/floatingdither.html

This old article also points out some mathematical problems:
http://www.jamminpower.com/PDF/48-bit%20Audio.htm

Perhaps someone more versed in dsp maths can point out the flaws
in these articles, and other hi-end audio misconceptions?

The primary use for 64 bit is the critical mastering stage, where it 
arguably doesnt make sense not to make use of available processing power.

--
Tim Orford