[sdiy] Re: Inexpensive 16 bit DAC?

[harrybissell]

If they do a multiply operation they meed more than 16 bits.

Changing the 'gain range' of a DAC is an easy way to add bits...
as long as you only want to add a small number of them.  If you want to
go from 16 bit to 17 bit... there is only one breakpoint you need to
trim, and
it could be easy to do (maybe not stable forever, but easy.

DeltaLab did something called "Adaptive Delta Modulation" which imho
kicked the sh!t out of the parallel units at the time.  Don't even ASK
about
the BBD of the time.

(that said... the BBD had the advantage of a very wide clock sweep
range...so
for chorus / flanger apps it would be the winner against ADM)

H^) harry

Mete BALCI wrote:

> 20-bit DAC in D-50, I dont know that. What is that for
> ? Do you think it is really needed or just for
> marketing purpose ?
>
> As I know D-50 is an hybrid (analog filters) with
> 16-bit samples, does it use its DAC immediately after
> the pcm wave generation ? If so, why is there a need
> for 20-bit DAC for 16-bit samples ? Does its internal
> processing is greater than 16-bit ?
>
> Mete
>
> --- Jaroslaw Ziembicki <aon.912230836 at aon.at> wrote:
> >
> > Around 1985, I would say. The 16 bit Burr-Brown chip
> > PCM54
> > (parallel inputs) was widely used.
> > In the Roland D-50 synthesizer there was a PCM54
> > plus an
> > additional resistor network to get a 20 bit
> > resolution.
> >
> > Regards, Jarek