[vdr] Re: AC3 and Denon AVR

["Reinhard Walter Buchner" <rw.buchner@freenet.de>]

Hi Ulrich, Andre,
 
> > Erhm, not sure there. It could quite well be that your amp is
> > running on the *edge* with PCM. Running the extra AC3 packets 
> > could just push it over the edge.
 
> Either the input PLL can sync onto a 5V sp/dif or not.

Well that is pretty much my point. The input was NOT designed
for 5V. So feeding a 5V signal into an input designed for 0.5
to 1V may very well still work (depending on how good the
rejection is), but adding more complex information (AC3)
may well make locking impossible. That like asking a 800x600
72 Hz monitor to sync to an 85 Hz signal. It may still work
at 75Hz or even 78-80Hz, but at 85 it just won't display.

I'm not even sure if it just the PLL. It may well be the D/A,
too. That will depend on the true input circuitry of the amp.

If the signal coming from the DVB is a little bit noisy, you
may never reach the intended 0 Volts long enough to be seen
as such and a input which has it max sensitivity between 0-1V
will be more susceptable to noise than an input made for
0-5V, simply because the "dead zone" is greater on the 0-5V
input. Extending the complexity of the signal isn't going to
be beneficial, either.

Using  an optical connection will surely remove all stray
ground interferences from the audio signal.

I didn't say it *IS* this way, but surely it is possible. I will
not risk the life of my Denon or my loudspeakers by testing
it with 5V. This is also the reason why my extension board
has a buffer driven ferrit transformer to make the signal as
HiFi conform as possible.

Testing it with a resistor divider sure won't hurt. Its up to
Andre to try it (or go for an optical solution). I just can't
believe Denon would skimp out on the input circuitry, just
because its a cheaper (smaller) model. Of course the D/A,
etc may well be different.

Greetz,
Reinhard


---
Mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.443 / Virus Database: 248 - Release Date: 10.01.2003




-- 
Info:
To unsubscribe send a mail to listar@linuxtv.org with "unsubscribe vdr" as subject.