The Reference 600 is ARC founder William Zane Johnson's masterpiece, described by The Absolute Sound as one of the 10 "most significant amplifiers" ever, a "lifetime achievement product" offering "breathtaking thermionic power that has no peer." These amplifiers are the last word in power, resolution and fidelity, musicality, and (did I mention?) power.
Boasting 16 (!) 6550 power tubes per channel and all-tube input and regulation, these things are behemoths--what Robert Harley, writing in Absolute Sound, called "a serious amplifier in every sense of the word." He continued: "But High End audio in its purest expression has never been about sacrificing sound quality to convenience or cost. The [Ref. 600] Mk. II is first about music; other considerations are secondary." The result? "A more natural sense of air and bloom than any amplifier I've heard.... It is as though the amplifier gets completely out of the way so that the instrument's dynamic range can be fully realized.... [A] benchmark level of performance."
The Reference 600 design remains the basis for ARC's current Reference 750 SE. And these amplifiers can power basically any speaker on the market--even (especially!) hard-to-drive speakers like Magnepans. Not many tube amps can match that claim.
The specs speak for themselves: 500 watts continuous output at 16 ohms from 20Hz to 20kHz with less than 1% total harmonic distortion (typically less than .05% at 1 watt). 600 watts peak. Per amplifier tube compliment: 8 matched pairs of 6550C power output, 4 6550C regulators, 3 6922 regulators, 8 6922 drivers; 2 6922 inputs. Musical output: pure bliss.
This pair comes with all-new Tung-Sol 6550 output tubes from Upscale Audio, with about 150 hours on them. The chassis have a few scratches, but no dents or major blemishes. They have been regularly serviced. I am the second owner and am reluctantly parting with them after moving to smaller quarters.
The amplifiers will be shipped in their original cartons, via freight, at buyer's expense. Or arrange your own pickup, if you prefer.
Find more information on this model, and pictures, at ARCDB: http://www.arcdb.ws/REF600/REF600.html