Part of the Rotel MICHI series.
Michi means "direction" and the RHQ-10 was named Shih : poetry, as written on this image.
At first with only three components, the Michi series was later complemented in some markets by one variant, two sources and a less expensive sibling :
RHB-10 dual-mono power amplifier
RHC-10 passive controller
RHQ-10 phono equalizer
RHA-10 active preamplifier
RHT-10 FM tuner
RHCD-10 CD player (big)
RHB-05 power amplifier.
The PCB of the RHQ-10 is made of high-grade fiberglass with 0,1% and 0,01% tolerance metal film Vishay resistors in the signal paths, eq and NFB loop.
The first and head-amp stage is a triple parallel differential fully complementary push-pull ; the second stage is a passive pole low-pass filter ; the third is a low frequency boost and gain stage.
The output stage is a single-ended fully complementary push-pull circuit in Class A. Discrete components throughout.
One input is available, with two outputs : Fixed 1 is for connection to a passive controller or preamplifier which bypasses the volume control ; Variable is for going directly into a power amplifier ; Fixed 2 is for connection to a passive controller or preamplifier when using a moving coil cartridge of extremely low output.
The MM / MC gain & impedance selection however remains mysterious and rests on "an ingenious method to minimize any adverse effect upon sound quality often cause by mechanical switching" - anyone ?
The gain switch/attenuator is supposedly the same 4-gang as in the RHC-10 but they don't look equivalent (and that of the RHA-10 is, again, different as well).
Power-supply is done by a (sizeable) low-leakage toroidal transformer ; dual-mono regulations throughout, copper bus bars, liberal heatsinking, sealed output relays, non-magnetic aluminium chassis and Teflon-insulated WBT terminals.
Like the RC-5000 and RB-5000, the Michi series was mostly made for the export market and is just as exceedingly rare.