linuxaudio.org

On Mon, 14 Mar 2005 20:49:03 +0200

Jussi Laako  wrote:
> Typical newsgroup FUD.
The paper referenced is this one:
   http://sjeng.org/ftp/SACD.pdf
by Lipshitz and Vanderkooy, two absolute *GIANTS* in the field of digital

audio theory and practice.
> First of all, most of current A/D and D/A converters are delta sigma

quoted text
> modulators. 

Yes, but from what I've heard, with modern delta-simga converters,

the minimum bit width is 4 bits, not one bit.
> If you record something at for example 24-bit 192 kHz (using

quoted text
> typical delta sigma converter),

The A/D converters now use a minimum of 4 bits.
> do some editing (in float format) 
Ie it gets convertered to PCM.
> and

quoted text
> then output the master as PWM for SACD.

They *may* be some advantage here in that you can pay for a very

expensive PCM -> SACD converter at the mastering stage and the

playback system becomes simpler.
However, Sony is pushing SACD as a complete solution for the whole

audio chain. Sony and others are working on SACD multi track recorders

and so on. It is this in particular that Lipshitz and Vanderkooy and

trying to address.
Erik

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  Erik de Castro Lopo  nospam@mega-nerd.com (Yes it's valid)

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