By chance I was able to participate in a group buy of these nice modules on the German diy-hifi-forum. Based on these modules I built two mono d-amp’s to play with. There is the technical data from the manufacturer site:
- Monoblock Amplifier 300W
- Residual noise <50uVrms unweighted
- 20Hz – 35kHz +/- 0.5dB ( -3dB @ 65kHz )
- THD+N <0,05% up to 300Wrms/4ohm @ 6,67kHz.
- +/- supply outputs for front end /crossover
- <1W stand by mode when delivering 150mW to signal sensing circuitry
- Over current protection
- Over temperature protection
- Over voltage protection
- 115/230VAC – jumper selectable
- Meets CISPR22 on conducted and radiated emissions
After some searching, I finally choose a case of Modushop, Italy: The Galaxy Maggio Rato GX287 230×170 mm (1NGXA287N). The boards are installed isolated on 15mm plastic spacers . The PE of the power cord is applied to the chassis only.
The switch at the front has a red 12V LED (I did not find one with green LED). The LED can be connected to the amp PCB without a resistor – but for my personal favor I’ll add one because it think it is too bright).
The holes I made with drill bits. Important is to cover surfaces with adhesive tape to prevent the anodizing to take damage from the clamping or chips while drilling.
The rubber foot under the housing Adam Hall PA enclosure feet 38×15 mm. Unbeatable for the price. Powercon plugs are used for the mains. They are really great: Super stable; and snap locked. A 3Gx1CY Ölflex cable fits fine. No comparison to an IEC connector. A round hole can also be drilled easier.
Finally, no hum or noise – just clean tight sound. They remain completely cold if driven at domestic levels.
Next step to come soon, is to switch from my current 2 way Acourate solution to “fully active”. I’m very curious. I can now say already, that the integration of room correction with Acourate is so far the largest step forward I made in my system for a long time. Just after I switched off the convolver/correction for the first time for comparison with the “previous” sound, it became quickly clear, that there is no way back: Imaging, tactile response and tonal balance is just so much better now. Acourate in my eyes is petty much the best invest one can to to the system, if you are willing to carry the transition to a PC based listening system.
Here are some pics of it: