Denon POA-A1HDCI - Manual (Page 9)

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The POA-A1HDCI amplifier damping
factor is about what I expected based
on the measured output impedance. It is
uniformly good across the entire audio
frequency range at around the 100 mark (50
is a minimum we like to see in all amplifiers
of uncompromising design) when driving an
8-ohm loads. Into 4-ohm loads the Damping
factor is exactly as expected, ½ the 8-ohm
value and buttressing the argument that
the POA-A1HDCI is happy to drive low
impedance loads at full power.
Crosstalk
Running a full range frequency sweep
through the POA-A1HDCI amplifier at
full rated power (150wpc @ 8-ohms), I
measured channel to channel crosstalk on
two adjacent channels where one channel
was the disturber and the other was the
Device Under Test (DUT). The Audio
Precision plotted crosstalk of both channels
over frequency by varying the Distruber/
DUT channels. You can see the POA-
A1HDCI produced very good crosstalk
measurements (>81dB at 1kHz) with only
a gradual rise with increasing frequency
because of capacitive coupling. Anything
greater than 60dB is deemed acceptable so
this is quite good for a multi-channel amp
that isn’t a true mono block design.
As expected, channel separation got
better as you moved the Disturber/DUT
channels further apart. It is interesting
to note that varying the Distruber/DUT
of the two-channels I tested produced a
crosstalk measurement difference of over
20dB. While both measurements were very
good, I couldn’t help to wonder how much
better it would have be if a bit more careful
layout was done to optimize trace routing
and minimize their coupling paths on the
circuit boards.
For two-channel audiophiles wanting the
absolute best performance this amplifier
has to offer, I’d suggest bridging the two
amplifier pairs on the opposite ends of the
amp labeled “FL” and “FR”, respectively. This
provides the maximum amount of separation
between them which is critical especially
during high power applications to minimize
magnetic coupling. As you can see in this
measurement, the POA-A1HDCI produced
Denon POA-A1HDCI Amplifier Damping Factor – Bridged Mode
Denon POA-A1HDCI Crosstalk Measurement Adjacent Channels
Denon POA-A1HDCI Crosstalk Measurement 4 Channels Apart
Denon POA-A1HDCI Crosstalk Measurement Bridged