It's a nice DIY project and that's a main thing. You're obviously happy. Although, Class D today is not just a touch of fresh air. They are taking the lead in the "big, clean power" domain. This becomes painfully obvious when you try to construct a 470w AB amp, we won't even mention A.
I agree with you that at the moment, Class D is expensive. But it's not the parts, it's performance driven high price. It doesn't matter that they have no large chunk of toroidal. Passive coolers are not an ornament or a bragging feature, they served a purpose which became obsolete and that's also good.
I'm glad to hear your amp stands ground when it comes to Marantz. Not so much YBA and D'Agostino, I think those are boutiquy overprioced BS. But, more importantly, what sort of problems did you have with vibrations? Why would it affect your amp and what is the physical noise of plasma screens? I've never seen any sponges on toroidals in conventional amps.
Thank you. I know it could have been done prettier. But I'm all about sound quality at the moment - as long as it's also electrically safe
I had the Vincent SAV P200:
https://www.hifiengine.com/manual_library/vincent/sav-p200.shtml
But it simply "cried" when trying to produce lower frequencies. I could literally see how the subwoofer swung and showed off how the amplifier lost grip. When borrowing the HPA2K, I saw how the cone of the subwoofer settled and made the driver play deeper and louder. Such an experience to actually see the big difference in "grip" or control between two amplifiers with the same driver unit - is something I clearly remember - and the reason I bought Groundsound amplifiers to begin with
I look forward to maybe transition to a sleek but powerful cabinet in the future, that pulls and plays like the 10 channels of amplifiers( 2 x 3x200W and 2 x 2 x 1000W) I have in my current system. But I had to start somewhere. And back when I began building fully active speakers... class D was more trouble than good and AB amplifiers were cheap and fitted well with freedom to play and experiment.
To get the furthest with less money. I found 4 identical transformers at a former job, for almost nothing. They are good quality, but a little old, and therefore they seem to hum a bit more. It's a droning noise, that seem to follow in the steps of the power usage from my plasma tv. So even though I changed a few caps in the power supply in my tv - and the noise did drop a little. I'm simply thinking of getting an extra outlet for the tv and computer, than the one for my amplifiers, to see if I can reduce DC interference.
It produces no problems in the sound - only my 6 transformers hum physically. So my trick/experiment was to suspend them in a foam cushion, to simply remove the physical contact between the amplifier casing and the transformer. Apparently the baseplate of the amplifier cabinet, acts as a sound transducer, and the foam simply dampens this to a very low level. A long bolt and locking not with pig shim, ensure that the transformers still stays put on it's soft "pillow".
My old Panasonic P50VT20E(bought used for 250$ 5 years ago) is known for it's noisy fans and buzzing power supply that change in pitch and magnitude, according to the amount of light scenes on the screen - but damn - always a great picture from this oldish technology.
Former owner got the fans fixed.... almost inaudible now. But I think the many little power supplies around the tv, simply start to show their age, which is just a natural thing I guess. now that I think of it... I actually think that the panel itself... is the one buzzing. Maybe I'll jump on a used OLED.... and then maybe I can hear new weird buzzing or humming from somewhere... as the disturbance goes away - haha
For now. I simply turn the tv off... when listening seriously.... the calmness that spread in the room, when only the music is present... is still a special experience.