Replace panel or add subpanel?

The sub panel is a great idea for convenience’s sake. You can run a 60 Amp circuit with 1 cable, and then have short runs to the room, giving you a number of dedicated outlets. If your listening room is far from the main panel, this is going to be a great, flexible solution, and may be cheaper than attempting to run multiple lines. Also, all your grounds will end at the same single reference point int he subpanel.

It may also be a good idea to update your panel. :)

And, if you want to go totally nuts, you can even put balanced, isolated power before the subpanel. :)

Best,

E

Erik, thank you. I should have added: the existing panel is at the bottom of the stairs to the basement, which will open first to the listening room. I think the best place for the outlet to feed the system in the listening room would be only 20 feet from the existing panel. In that case, would there still be any benefits to a subpanel, leaving the existing panel unchanged? 
As for my mental status, I went off Into crazy land with my choices of gear some time ago... 🙄

I think your electrician is giving you the more economic solution with a sub panel vs. a complete replacement.

If you already want to replace the main panel anyway, say to clean up code violations and/or breakers being used for more than 1 run, then sure.

OTOH, if your listening room was 60' away, and you wanted to run 4 or more independent circuits then a sub panel would be a really good idea.

Also, never underestimate what you may discover and have to pay for with a complete replacement. :-)