After many years of effort, I have arrived at a system based on high value components. I recently upgraded the speakers, power amp, AC power filter, power cords, and speaker cables and I am very happy with the results.
My backup pieces can be seen on on shelf on the right behind the system: a Nakamichi 610 preamp and an Adcom GFA 5200 amp.
The room is a combination office and sound room:
It is a ground-level (1/2 basement) room with a concrete floor, and concrete and wood walls
The room has a dead-end / live-end acoustic
The AC outlet feeding the system is on a dedicated 15 amp line
The last upgrades I have planned are a new phono cartridge and acoustic diffusors for the ceiling.