Grumpy_Mike:
Well I would filter before the high current driver. This is because the capacitor is much smaller and so the circuit is more reliable and has a longer life. It is easer to deal with the heat generated by a linear buffer than the life time of a large capacitor switching gob loads of current.
It's certainly a trade off. I own a vintage late 70s Pioneer SX-1980 stereo receiver. Rated at 270 WPC RMS @ 8 ohms, it weights in at 78 pounds. No fans but hugh heatsinks. A modern equievlent would probably weight 10 lbs and sell for $200.
" Its retail price in 1978 was $1295.00. According to the average historical price of gold, it would have listed for an equivalent of $8199.42 in 2010"
Lefty