Luxman B-12

Part of the beautiful and renowned series of ultra-slimline components taking things where the Laboratory Reference Series left off :
C-12, M-12, B-12, T-12.

Several other siblings were also around for those who couldn't spend 500,000¥ for a complete "12" set : L-10 integrated, T-10 tuner and the (completely different and not slimline at all) L-11.


The B-12 is a compact 150W monoblock with bigga toroidal transformer, bigga 15,000µF caps (two) and triple push-pull based on the Lux Realtime-Processed DC circuit.
Regulated driver stage is in Class A, output in sliding bias Class AB but I don't know which output transistors were used.

Realtime-Processed DC relies on a proprietary IC, the DML-01 which holds the first stage differential amplifying circuit, the cascode circuit to assist it, and the constant current circuit all in one (little) box.
Those ICs are alas NLA and have proven not completely reliable...

The back has an input attenuator, 6A fuse, one RCA input and a switch selecting either DC mode or input coupling for electrostatic speakers.

Luxman sold many B-12 monoblocks and stereo M-12 : they sound good, very good, and they look very good.
The design puts the transistors at the front of the enclosure, encased in between their respective heatsinks, partly hidden under a meshed grill.
Striking. Even if full-black in color was a bit... dark.


Being from the 1977-1978 era, B-12s all have an LCJ T-Tag with #G9101xxx, #L7100xxx or #G8100xxx serial numbers.
They were "customed" by LCJ, customed meaning here that the 12s were limited edition - small numbers.



Still awaiting more from Japan but the Luxman single-component japanese catalogs are almost always quite disappointing.
But I know I have at least two THD graphs coming :)

A pair of B-12 at hifi-do's and a bias current thread here.