All of our electronics run on DC, rectified from AC mains. So you can use the DC from solar charged batteries to directly power the electronics, bypassing the AC rectification. In some components, especially low current devices like source, you can use the existing DC regulators. High current devices like power amps are often not regulated, so you'd need to supply correct DC voltage, or use high power regulator. The only one I know of suitable for "high end audio"
is the Belleson 100VDC @10A.
Example, my chip amps use +/-28VDC power supply to make 60wpc. They will run fine on 24-26VDC. A charged battery is about 13V, so I can run 4 batteries in series, picking up the ground in the middle and getting -24V from the negative end and +24VDC from the positive end of the series batteries. Charging solar panels are connected to each battery's own two terminals. Good batteries like Optima Red have low impedance and low noise, so they make good audio PS.
A music server PC, TT, and DAC will run on 12VDC input, or rectified lower as needed, but tubes need high voltage DC so you'd have to regenerate that. Very little current is needed for line level tubes, so you could generate it with the above 60W amplifier playing 60Hz sine wave through a step up transformer to make the high voltage DC for the tubes. I think running tube power amps on solar wouldn't be worth the effort. Fire up the generator for that.