I am confused about 15A and 20A current.

Your Refrigerator could possibly be on a 20 amp circuit. Try plugging the whole mess into that outlet. If that circuit breaks, then that tells you something.

Refrigerator, plus kitchen counter tops, washing machine, plus typically one in the dining room since at least the 1975 NEC.

Unless someone has removed the amp's fuseholder and wirenut'ed the leads together, the amp fuse will blow *much sooner than the branch circuit C.B. (Time-current curves...)

You cannot just swap out a 15A breaker for a 20A. You must have at least 12/2 romex running from panel through the walls to accommodate the 20A breaker. When you just swap out breakers as above, you will over heat the romex wire, being that the 15A existing circuit is wired with 14/2 romex. If there is room in panel, then add a new 20A dedicated circuit for the hifi, which entails running new 12/2 romex from panel to new receptacle, which by the way must also be 20A. Yes, a bit of work indeed, but safe and solves the issue. Lastly, most prior answers suggest 12/3 romex which is not correct for the application. All you need is 12/2 (black/white/bare copper ground). The 12/3 contains a third conductor, red, and is typically used when installing a three way switch.

17 year old post