SPDIF or AES/Ebu interface

[Rob]

I could see an adjustable tube gain stage AFTER the dac, but...

I don't see what gains you would get from having a tube dac.

Rob
----- Original Message -----
From: Magnus Danielson <cfmd at swipnet.se>
To: <buchi at takeonetech.de>
Cc: <synth-diy at node12b53.a2000.nl>
Sent: Saturday, September 02, 2000 5:53 AM
Subject: Re: SPDIF or AES/Ebu interface


> From: buchi at takeonetech.de (Michael Buchstaller)
> Subject: SPDIF or AES/Ebu interface
> Date: Thu, 31 Aug 2000 15:38:33 GMT
>
> > Hello Group,
>
> Hallo Michael,
>
> > i am in the process of building a tube-based DAC. First experiments with
> > a 8-bit-version vonnected to a PC´s parallel ports look promising.
> >
> > But i want to have a digital input via SPDIF (or the like), so i could
connect a
> > CD player or other gear directly.
> > Having looked at various data sheets of SPDIF decoder IC´s, i am very
> > confused. Is there anything out which would allow me to simply convert
the
> > serial data stream into a parallel one ? It seems that all the IC´s are
designed
> > to be interfaced to a MPU or at least to a DAC IC with serial input.
>
> Yes, but then add a few chips to do the serial to parallell conversion.
Since
> quite some time has the audio/hi-fi industry been using serial devices
since
> it gives supperiour pin-count/function ratio. You can find very nice
stereo
> DACs in a 8-pin capsule for instance.
>
> However, what I am woundering is really what the point is here... are you
> really using tubes as the fundament switches of the D/A ladder?
>
> I'm not a tube-head, but how well can one calibrate them as stable
switchable
> voltage or current sources? As you go for more bits this will become more
and
> more important since it causes distorsion, and not the kind of distorsion
that
> you are looking for.
>
> Anyway, if this is what you are intending to do it certainly sounds like a
> odd-ball project. It would be interesting to see how it turns out.
Personally
> I would stick with a commercial linear DAC.
>
> > I would really want to avoid a provessor to do this task; any hardware
solution
> > would be preferred.
> > Does anybody out there have experience in this field ? Specially,which
decoders
> > are working fine, and which ones are better avoided ?
>
> Well, I would be looking at the Crystal Semiconductor ones to start with.
>
> Cheers,
> Magnus
>