Important differences/improvements I forgot to mention…
the 976 is 4K ready - it’s far more than a 975 w/ balanced outputs.
Comes w/two sub outs both XLR & SE though they really just save the user from having to buy/use a splitter
More HDMI inputs, TWO HDMI outputs, and for a few $s more Bluetooth connectivity.
Finally the most important diff - better sound quality!
tony