Denon POA-A1HDCI - Manual (Page 5)

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stable performance with low impedance
(4-ohms) speaker loads, even in bridged
mode. In fact this is the industry's first
4-ohm UL rated amplifier I’ve come
across. This is quite an engineering feat
for a multi-channel amp which requires
a helluva lot of heat sink area and high
current devices to double down its
power with halving load impedance while
meeting the stringent heat dissipation
requirements of UL. To do 150wpc into
8-ohms like this amp is rated, you need at
least 55V rails so the 80V caps have more
than enough design margin to ensure this
amp can deliver more than rated power
and not get wigged out during high line
voltage conditions when plugged into
a power conditioner that does voltage
regulation. The POA-A1HDCI appears to
be a very conservatively rated 150wpc
x 10 amplifier with good headroom to
help prevent clipping during high power
demands.
Listening Test
CD:
Dianne Reeves
Never Too Far
This is the first
CD I turn to when
initially calibrating
a system as many
of the tracks in
this CD are an
awesome test for a system's bass response
and accuracy. The bass track in Track #2
“Never Too Far” will sound muddy or weak
on an improperly set up or inadequate
system. I initially ran just my front main
speakers bridged to the POA-A1HDCI to
determine how cleanly they would play
once I started pumping the volume up. The
presentation was free from audible strain or
graininess and the system's bass response
was tight and articulate - just as it should be
when driven by quality electronics. The tonal
balance seemed slightly more forward than
what I recalled when the amps in my Denon
AVR-5805 were powering my speakers but
it also seemed more grandiose. I found the
POA-A1HDCI displayed excellent stereo
separation portraying Dianne’s powerful
vocals dead center. The drums had a nice
pop to them while the saxophones exhibited
a nice bite giving you that “live” feeling. The
soundstage was very expansive making me
feel the “never too far…" chants from the
backing vocals where emanating from my
side channels despite the fact that I was
only listening in stereo. The POA-A1HDCI
maintained a very clean composure even
when driven to LOUDER than comfortable
listening levels in my nearly 6,000 ft^3
Auralex acoustically treated listening room
sitting 16ft away from my speakers. Switching
over to PLIIx Music mode was like being
thrown right into a high power nightclub.
Now I had all the speakers powered off the
POA-A1HDCI and instead of running out
of gas, it seemed to want to play louder so I
continued increasing the volume hypnotically
watching the needles on the power meters
pump away flirting into the red +4dB levels
during bass transients in track #3 “Come
In”. The floor in my theater room shook as
if it was alive and the transients in the sax
sent chills down my spine. Although this was
insanely loud, it didn’t at all seem strained
and I had to remind myself as my SPL meter
hit 110dB transients that I was listening at
unsafe levels.
SACD:
Patricia Barber
– Night Moves
Track #1 “Bye
Bye Blackbird”
revealed that the
POA-A1HDCI can
handle
delicate
musical passages
with authenticity. Piano music is very hard
to accurately reproduce as the harmonic
overtones are quite complex. The POA-
A1HDCI’s low noise floor revealed all of
the nuances with plenty of depth at airiness.
I heard all of the presence in the cymbals
of Track #2 “Invitation” with plenty of
body in the music. Bass was abundant and
well extended in track #3 “Yesterdays”.
I switched the processor to pure direct
and just sat back listening to pristine two-
channel audio that would make even the
most critical of audiophiles drool over. The
Denon gear was driving my speaker system
with ease and adding no sonic nasties
that would distract my enjoyment of the
listening session no matter what power
level I was running at.
CD:
Pat Metheny –
Off Ramp
No serious
reviewer forgets to
throw in a little Pat
Metheny in their
product reviews,
especially when
testing out top echelon gear like this. I
pulled out an oldie but goodie and took
it for a spin using PLIIx Music Mode. I was
“The Denon POA-A1HDCI
is a no holds barred, no
compromise multi-channel
THX Ultra2 certified
amplifier design that
represents some of the best
engineering I’ve seen…”
Gene DellaSala
Once an amp runs out of headroom
it enters a mode commonly referred
to as “clipping”. When an amplifier
clips it essentially sends a square wave
response or DC voltage to the speaker
which after only a few short cycles
can fry a tweeter's voice coil or burn
out series inductors in the crossover
sections.
Editorial Note
on Amplifier Clipping