Way OT, but a few of you are still involved in electronic design. Wondering what is hot and new in audio amplifier design- I've built many, but now I want to eliminate the main power transformer if I can by using rectified ac to start with. The option still exists from a single phase supply to create the plus and minus voltages from a bridge rectifier, so for an amplifier I'd have the split supply as usual, but at the higher voltage of +- 160vdc.
Isolating the input wouldn't be that much of a problem, so the problems that do exist are the danger from the output wires being direct connected to ac power, and the requirement for higher voltage transistors for the outputs. Matching the speaker impedance is another issue, but one which can be resolved by making series connections instead of parallel to what would have to be multiple speakers per cabinet.
What I have in mind is to have the amp inside the speaker cabinet, or in other words, powered speakers. I have no problem to ground all the baskets, but there isn't a lot of space between the voice coil and the magnetic structure. The potential for arcing is considerable.
I'm not sure that I'm willing to rely on an optocoupler to pass the input signal and isolate any potential for an accidental connection from the input to a live wire.
I also know that by using a high frequency transformer I can get both the isolation and suitable power supply voltages to run an amp of whatever wattage I design for. Then I wonder why not set this up to deliver a voltage that tracks the output voltage and stays say 10 volts above the requirement at all times. I think this is a derivative of class G, or is it H- don't recall.
Any thoughts on this from anyone?