NEC A-11

After a first series of mid-end separates ("Authentic") in the late 1970s, NEC went all out with the new decade and for the upcoming new format : 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 !

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 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 8x 8200µF / 50V caps ; preamp filtering is done by 6x 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.

Although NEC constantly upgraded its A-10 sibling, the A-11 remained as it was produced in '83/84 and is very rare.

All japanese catalogs finally in my hands for the entire series - stay tuned !