A life time of buying and selling to upgrade. I started 40 years ago. My 20x12x8 room is the biggest limiting factor. Two dedicated lines help power the system with one wired with 10 gauge instead of 12 gauge code. A definite sonic upgrade is my DIY speaker bases. I have wood floors and these tighten up and lower the bass quite a bit. Its not a subtle difference either. Here is how to make them.
1. Start 4 aluminum cones. I used my old Mod Squad Tip Toes but any ones will do.
2. 16x16 slab of granite.
3. 1/4 inch cork.
4. 1/2 inch neoprene rubber. The extra 1/4 inch made a small difference.
5. 1/4 inch cork.
6. Top it off with another 16x16 slab of granite.
7. Finally a wood cradle to hide the mechanism.
It's based on well known industry isolation/damping standards and a wealth of information fellow Audiogon members have shared.