Update on Nov 12, 2009:
FFT measurement:
So you can see the noise floor is not great at about -110dbV.
Last update on Sep 11, 2008:
This is a professional DAC made by Yamaha back in 1988. It was made for the DMP7D digital mixer in the same period using PCM56P-K x 2 and IC op-amps JRC 2068 and NE5532. Yamaha use a custom IC YM3023 to switch the 16bit DAC into 18bit. The digital receiver chip is Yamaha YM3623B. The power supply is a linear regulator.
