OK I guess will jump in. The best I have ever heard is what I am listing to right now. I am running a set of Altec Valencias with an upgrade to the 908-8 horn driver. The signal comes from a Nakamichi CD2 player run through a set of Heathkit XO-1 tube crossovers. The crossover frequency is 1200hz. The split signals are sent to a pair of Heathkit W-5s, fully restored and upgraded, Gold Lion KT66s. The W-5s handle the frequency abouve 1200hz. The low signal is sent to a pair of Heathkit W-6s amplifiers that were rebuilt to better than new condition by NOS in 2009. I am running Gold Lion KT88s in them. The reason it is the best is the output transformers. The peerless transformers are consider by many, with graphs to back it up, as one of the best audio transformers ever made. There were only 1000 pair of these amps made. The bi-amplification using tube equipment make my current set up the best I have ever had. I have owned hundres of audio componets and have been in the elctronics field for over 35 yrs. Audio isn't a hobby to me. It's my passion. BTW I have La Scala, Cornwalls, Heresys, and several other Altec horn systems. Every thing is run with tube audio. I have at this moment over 17 amplifier, a few preamp (tubes), and too many other things to mention. So, thats my story and I am sticking to it. The W-6s are capable of hitting 140 watts without distortion. The W-5s, after mods, are one hella set of amps. I am at the top of my journey.