The on-board amplifier is secured to the steel back plate. The bi-amp design delivers power separately to the woofer and tweeter with 65 watts peak power to the former and 25 watts to the latter. According to the print on the amp board the M-505v2 studio monitor shares the same board but with slightly lower power output.

An aluminum heatsink is used to cool down two power transistors. This heatsink is attached to the back plate to transfer the heat outside of the speaker box. After a couple of hours of use the back plate feels very warm. I would not leave active speakers on all day as the heat will certainly shorten the life of the amplifier. Class AB amplifiers, by design, waste power by converting it in the form of heat even when there is no input.

I was concerned about having an amp inside a poorly ventilated enclosure. This is where out-board amplifiers have an advantage. I wish the entire back plate had aluminum fins on the outside for better heat dissipation.

Here is a shot of the two main filter capacitors. The other smaller electrolytic capacitors are mtdcon brand. Not brands popular with the audio community for sure. They are rated at 105° C, which is good considering the heat build up inside the speaker box.

I believe these are opamps. There are six of them. Interestingly, I do not see a single inductor coil of any kind for the crossover. I believe this amp employs an electronic crossover instead.



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