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Nec
A-11
(1983 - 1985)
After
a first series of mid-end separates ("Authentic") in the
late 1970s, Nec went all out with the new decade and new format
: the CD-803
was among the top CD
players in 1982/83. Then, the original A-10 amp was engineered to
cope with said new format's dynamic range - its many subsequent
versions were biased toward that : POWER !
It
wasn't high-end audio, though, and Nec never went there, except
with its three top CD players (CD-803 ('82), CD-903
('86) and CD-10 ('89)) and a couple of discretely distributed
amplifiers just before vanishing from the consumer audio landscape
in the mid 1990s.
But the A-11 sure was built like few mid-end amplifiers were in
those early digital days : all steel, all metal, three mutha toroidal
trafos and a special audio engineering slant which was kept until
the last version of the series in the very early 1990s : A-10
Type V.
The
two main transformers are dedicated to the left and right channels
with separate windings for their respective section ; the third
transformer (the one that embodies the "Reserve" tag)
comes in whenever more current is necessary. While in a regular
power supply, tension coming out of a transformer is rectified then
filtered, in the Reserve II scheme, a second double-winding transformer
kicks in after the rectifying and before the filtering, to smooth
out the two rectifying phases.
Power filtering is done by eight 8200µF/50V caps ; preamp
filtering is done by six 2200µF/56V caps. HifT power transistors,
pure complementary DC circuits, low-noise componentry.
Like
a few other amps at that time, the A-11 can be separated in two,
used as an amp or as an integrated amp/preamp. If separated, only
one input is accessible and the two volume pots act as volume &
balance. Said system thus circumvents everything but the two pots
and the power amp section ; the power amp's swift rise time is however
slightly hampered when using the CD Direct path as a LPF filter
was added to that input... Square wave response remains truly excellent
throughout the audible bandwidth which the A-11 extends to 300kHz
btw - very harman/kardon
like.
The ad image above shows a pre-production sample which hadn't yet
written "CD" next to the operation switch ; the images
to the right show it as finally produced.
Although
Nec constantly upgraded its A-10 sibling, the A-11
remained as it was produced in '83/84 and is very rare.
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