My two dedicated 20 amp lines, with FIM-880 outlets, did improve the bass. My friend the electrician, not an audiophile, even noticed it.
However, I don't think electrical is your problem. I recently had a similar condition, i.e., lean sound with a lack of bass, that was caused by the two 12ax7 Mullard gain tubes in my phono preamp subtly degrading over time (one year) until it became so pronounced I inquired about it.
I never would have guessed it was the tubes. I had two Electro-Harmonix 12ax7's on hand and swapped them into the phono preamp. Musical nirvana! I had no idea how far the sound had degraded until then. Everything came back, the meat and body of the music, the soundstage even improved.
I also found another audiophile who routinely changes the tubes in his preamp for the same problem. Perhaps the Mullards both went bad in a subtle manner and the EH tubes won't. I know I'll be aware of this, and swap out tubes just to check them in about a year.
However, I don't think electrical is your problem. I recently had a similar condition, i.e., lean sound with a lack of bass, that was caused by the two 12ax7 Mullard gain tubes in my phono preamp subtly degrading over time (one year) until it became so pronounced I inquired about it.
I never would have guessed it was the tubes. I had two Electro-Harmonix 12ax7's on hand and swapped them into the phono preamp. Musical nirvana! I had no idea how far the sound had degraded until then. Everything came back, the meat and body of the music, the soundstage even improved.
I also found another audiophile who routinely changes the tubes in his preamp for the same problem. Perhaps the Mullards both went bad in a subtle manner and the EH tubes won't. I know I'll be aware of this, and swap out tubes just to check them in about a year.