Original owner with original tubes never re-tubed, but needs to be otherwise excellent condition. These are the pure MB450's. The MB450 ll and the $ 20,000 lll only difference is you need to bias yourself andwithout all the extra circuitry, and well the word on the street is the new auto bias circuitry actually harms the sound. Both units have been inspected by a VTL authorized service technician and invoice available. Read the reviews. Simply the best for the money. Will run 6550 or KT-88 tubes. You can choose what you would like run, original VTL tubes, something more basic or exotic from the tube store for about $600. Giving you that $20,000 sound for a fraction of the cost. At this price you could even get a extra pair of KT-88 and decide which you like better and then sell the others here on Audiogon. These have the face plate so you can watch your tubes glow. Best of both worlds, lush tube sound with hard hitting 450 powerful bass. This review is about the pure MB450. In tandem with the VTL TL-5.5 tube line-stage preamplifier—review to appear next month—the MB450 monoblock evinced larger-than-life levels of midrange liquidity and dynamic drive, massive bass control, captivating high-frequency purity, and out-of-this-world, holographic layering and depth. I've never had anything in my system that delivered more goosebumps per square inch than this combo.
Read more at http://www.stereophile.com/content/vtl-mb300-mb450-signature-monoblock-amplifiers-chip-stern-2002#5lGgS52QFxxEflrZ.99