1. ARC GS150 driven by McIntosh 275: Not enough grunt;
2. Luxman M900u solid state driven by Luxman 900 control preamp: Too slickly musical for my tastes, I missed the tube grain;
3. ARC 250SE tube monoblocks driven by Luxman CL1000 preamp: Great sound, speakers controlled well - great bass, midrange and treble;
4. ARC 160M tube monoblocks driven by Luxman CL1000 preamp: My dream system, especially after Sasha DAWs arrive next week.
I should add that I do not stream or play vinyl - I use an Esoteric 01-XD SACD player as source with an external 10MHz master clock. All cables top quality. AC power is pure, direct from the transformer. Dedicated, well engineered speaker room in basement of a large house in rural Michigan. The sound now is lovely!