I live in a small home where I cannot dedicate more than one room for A-V. I have removed a door and window in the speaker-half of the room and started improvements from there. Most recently, my wife decided we needed to go with higher sensitivity speakers and she remembered the way a friend's Bozak Concert Grands sounded. Found a pair of B-302A and decided to upgrade this classic system with current technology. Crossover is mounted on the read [mostly 4th order Bessel] and the satellites now house the mid and tweet. Another super tweet [Fc=12KHz] adds the crispness and ambience. Sensitivity is about 94dB/W/m and the MC2100 amp pushes them well. I tri-wire from the amp terminals to the speakers where each driver has its own network board. Most significant changes were PIO caps in the network and star-quad wire everywhere from the output autoformers to the driver terminals. Wires are star-quad all hand made from either OCC magnet wire or stranded-silver/Teflon or wire-wrap [silver-plated OFHC, Teflon]. Internal amplifier was completely rewired point-to-point with OCC+silver Litz. Of course everything is hand-matched from the T-pad attenuators on the drivers to the emitter resisters in the amp [all non-inductive] and the system is powered by sunlight [photovoltaics]. I could go on because there is much more in the way of upgrades and mods but you get the idea. Current electronic components are OPPO BDP-105 [streaming and video], Onkyo P-3000R preamp, Mcintosh MC-2100 power amp, Pioneer PL-L1000 turntable with Sumiko LMS cartridge, hand-made pre-preamp for the low-output MC. Wires are all hand-made as are interconnect cables. HDMI are the Pro versions from Tributaries. Power cords vary and the line conditioner is a modified APC S20BLK. Also a generous sprinkling of custom RF/EMI suppression here and there. There is one dedicated 20A line that runs from the 15KW 48V pure-sine inverter to the A-V system [read everything is on the same electrical phase]. Speakers are modified down-firing Bozak B-302A with two B-199A woofers per box [isobaric]. Solid granite 1.5" thick tops and tiptoes on legs. Satellites are Bozak B-209A mid, Mundorf AMT164UM2.3-R tweets, and Bespoke Aria super tweets. Passive network is mostly 4th order Bessel with 2nd order BW on woofer LPF and mid HPF. Network inductors are mostly ribbon [Toroid on the woof LPF] and capacitors mostly PIO and Teflon.