[quote="albee" I presume at that price the 2024 boards are stock with no mods, right?[/quote]
Oh no. Plenty of mods, that's what makes the amp sing. Stock it's a little flat.
The input circuit has been redone with a Nobel pot, Panasonic ploypro caps (off board, they're large), better resistors, larger Panasonic FM cap on the PS rail, toroidal inductors on the output, good quality output caps, RF management, rerouted onboard signal and power. To mention a few.
Also comes with a big regulated PSU, no batteries needed.
I did not like the sound of the stock Sonic Impact unit, couldn't understand what all the fuss was about. Modified, it's a wonderful amp. Amazing, really.