In article , Arny
Krueger
wrote:

"Chris Morriss" wrote in message
...


I would be wary of the SNR at the outputs though. My hearing is not
at all good any more, but the noise level when using one of these at
low output levels is not really adequate. The solution is to follow
the unit with a multi-channel analogue gain control (rather than
using the internal digital gain control), so that the crossover is
working at a high internal signal level.


Inside the box, the digital data path is 24 bits wide, and you have
misset levels by a mile to have noise there.

At the output of the box, the transition into the digital domain is
designed, per pro standards, for FS = approximately 10 volts RMS (+22
dBu)

That was my understanding of the specs in the manual. Although it also
mentions +12dBu, but I wasn't clear if that meant both input sensitivity
and output level for 0dBFS could be set to that as an alternative.

Most power amps have input sensitivities below 2 volts for full output,
so approximately 16 dB worth of available dynamic range are lost. The
unit has approximately 110 dB dynamic range, so losing 16 dB puts you
down at 94 dB which still isn't all that bad if you actually set levels
that way. Many people miss that goal.

I would need to test the unit to really know, but my inclination would be
to always keep well below -6dBFS anyway since otherwise some internal
processes might overflow. All depends on the details of the internal
processing. With genuine professional gear I'd assume this isn't a problem.
But with 'prosumer' or 'amateur' - or 'audiophile' - I'd be more wary
initially.

FWIW It seems to me to make more sense in a domestic audio situation to use
something like the DEQ with digital in and out. Cuts down the number of
conversions, and also lets you use a consumer DAC which outputs the more
familiar (for home use) Phono/RCA with circa 2V for 0dBFS.

That said, I've still personally come to no conclusions about the need in
my case. I may well end up deciding that the Quads with my modified Quad 34
are still fine for me. May try a sub or something like the DEQ out of sheer
curiosity. :-) More likely I'll just be 'distracted' by listening to
music, though! Recent Proms have been great, and I've been ordering and
getting some more Jazz CDs. Perhaps I should start another thread about
that...

Slainte,

Jim

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