Just a curiosity but maybe some people could be interested.
For some time now we make some attempts with Lord Vader, to force full synchronisation of TurboSound (2 x AY) and GeneralSound (4 channel digi music in 8-bit quality).

General Sound's bus is only the Nemo-bus anyway, so we by default try to make it for spectrums with int rate of 48.8 Hz (Pentagon, ZX Eva and so on).

This is not any real song, it's only the first short result of the work -

We have now a full synchro for Spectrum trackers' speed "6". On Amiga it would be tempo command "F7A".

Considering that two AYs give 6 channels, with General Sound it give us 10 channels in total.

Will it be useful? It's hard to say yet, but there is such a possibility.

Anyway, it would be rather for chiptune/lo-fi musicians because there would be no point to use it in demos/games, as all ZX machines have different level of AY/GS mixing (sadly).