The HFX® mini class.d is fully controlled by the connected HTPC. It is connected with analogue line-in. Volume and on/off as well as software equalizer, sound effects and Dolby Digital modes are controlled by the HTPC.

Class.d high-grade audiophile amplifier modules from HYPEX ensure highest sound quality at maximal sound pressures.

Enormous passive cooling capacities reveal the whole potential of the amplifier modules. The product design interacts with the HFX® mini series for Home Theater Computers (HTPC) and Storage box.

The HFX® mini class.d amplifier is completely produced in Austria in a limited quantity production.

Features
>> 5x180W class.d amplifier modules "HG" audiophile from Hypex
>> 3 high end transformers inside
>> Remote soft on and off with PC
>> Connection to PC with analogue line-in
>> Passive cooling with heatpipes

Connectivity
>> 5 SPEAKERS (front left, front right, centre, rear left, rear right)
>> line-out for subwoofer
>> AUDIO IN Stereo RCA
>> REMOTE ON/OFF IN and OUT*
>> 240V AC with Fuse (110V AC on request)
* if the HFX® mini class.d will be connected with a laptop, then a 12V PSU is needed to simulate the remote on/off. This 12V PSU is part of the package contents.

Specification Amplifier
>> 5x 180W RMS (4 Ohm)
>> overcurrent and overvoltage protection
>> soft clipping
>> THD: 1%/0.1%/0.008% at 180W/90W/1W at 4 Ohm
>> Frequency: 10Hz-50kHz
>> Efficiency: 92% at full power
>> Idle loss: 4W
>> Standby current: 0mA
>> Current limit: 10A per channel
>> Net weight 16kg
>> Dimensions: 43x40x10cm

Package contents
HFX® mini class.d amplifier, 12V external PSU for remote on/off, slot sheet for remote on/off, remote on/off connection cable,

Reviews:
http://www.hardwareanalysis.com/content/article/1822.5/
these amplifiers convince by their excellent sound quality, ability to drive difficult loudspeakers and offer a true and lifelike reproduction of the signal offered at the input, without adding something to or subtracting from it. So in summary we can conclude that these amplifier modules offer an excellent price versus performance ratio and come highly recommended.
http://www.tnt-audio.com/ampli/udc180_e.html
As a matter of fact the presentation of sound is quite similar to a good class A amplifier or a single ended triode unit. Something - so to say - very different from the T-Amp, that I'll use as a reference, just because it is another widely known example of new Class-D technology amplifier. The sound is clear, rather transparent, precise, detailed, with that specific "lucid" presentation typical of triode units.
Low frequencies are well present and controlled, even though perhaps not as much as you would expect from an amplifer with a damping factor of 400. The entire bass range is definitely round and full, pleasant and effective, exactly as it happens with many tubed amp systems.
Mid range is clean and smooth, not especially in evidence, but enough to give voices the correct body and appearance.
High frequencies are open, clear, lucid, really tubey. Given these qualities, the unit does not forgive sources with a "digital" flavour in the sound! In such a case the sound becomes rather "viscid", unnatural and as such unpleasant. Otherwise, it is limpid and smooth.
The soundstage is very wide and precise. No artificial depth seems to have been added, but all the natural depth of the recording is correctly presented. Despite the precision in the instruments portraits and in their positioning, the music, again as in tube units, tends to appear more as a whole than decomposed and dissected in its components as with T-Amp, for example. So the soundstage is very natural, very realistic, and very involving.
The black areas among instruments and players are therefore vibrating with music, instead of being empty like it sometimes happens with the T-Amp. However, a lot of details and ambience informations are transferred to the listener while that strange (T-Ampesque) feeling of shortened sound queues is completely missing.
Anyway, while the sound character is in some way similar to the SET's one, the energy delivered to the loudspeakers is a completely different thing: even with my speakers, which in spite of a relatively high sensitivity of 90-91dB are well known to be a difficult load, the power is definitely there, and even though I still have not found the amp that makes them really fly (in facts no one of the amps I tested through the years have been able to fully achieve these result...), I have never heard them getting any closer to the take-off.

Manual
http://www.hifiatx.com/ftp/manuals/manual_classd.pdf

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