Reviews

Ming Da is company based in China that exports tube preamplifiers, power amplifiers, and integrated amplifiers in various price ranges, including some very high end models. They sell direct, through Pacific Valve, rather than through dealers, so you really get a good bang for the buck. In this review, my first of a Pacific Valve product, is on the MD-75, which is a stereo integrated amplifier. It has a detached power supply for low noise and interference, a remote for the motorized volume control, and you can switch between triode mode (40 watts/channel output) and ultra-linear mode (75 watts/channel output). You can "tube roll" if you wish, and the review unit came with optional Black Treasure CV-181 driver tubes and Black Treasure KT88 output tubes.

One very nice feature of this product is that, when you turn it on, the volume control rotates to the lowest volume setting, so you don't accidentally start playing music at a volume that might startle you.

This second part of the HK 990 review examines the signal flows in the HK 990 dual-domain integrated amplifier. This analysis is relevant to all units, including modem AVRs, with a DSP signal processing unit in the main signal path. The signal flow is more transparent in this stereo unit than a 7.1 multichannel unit; so, if you are interested in AVR, please stay tuned in to Part II.

The HK 990 is a truly unique stereo component. It is a dual domain device capable of accepting analog or digital inputs, converting domains as required, and sending the results to the speaker.