Our house was built in the '60s also, and some of the wiring was somewhat upgraded and some was the original 2 blade outlets and it had the glass screw-in fuse box. One of the best (and actually relatively affordable) upgrades I ever did was to buy a circuit breaker panel at either Lowes or Home Depot (this was about 25 years ago, so some of the detail is a tad foggy) and then I installed some new outlets for my system and then I ran ROMEX down the walls and through my attic to where it could come down and meet the new panel and then I hired an electrician to install the box and hook my new circuits up.
I have read a ton of ongoing & recent threads on this forum and the amps/preamps forum since October, and by scrolling down to October in both forums, I am sure you would come across them. Everyone seems to agree that a good circuit is a cost effective upgrade; there disagreement on the best way to run the circuit(s).