Audio Research's "Magnepan" Amplifier

My last stop of the day, and of the show, was the Audio Research room. Dave Gordon showed me their new DS-650 (I'm not sure that the designator was DS) stereo amp and laughed that it was their "Magnepan amp." Yup, I agree. As I discovered when I paired a pair of MG-3.6s with Classé CAM-350s, while any competent 20Wpc amp will drive a pair of MG-3.6s adequately...any top-notch 300–400W amp will actually drive them well. Then Dave casually noted that the 650 was a class-D amp and told me to put my hand on its top. Sure enough, it was cool as a cucumber in spite of having been on and making music for several days. "The entire amp is ours, from the bottom up," Dave noted, "there's nothing standard or off the shelf in there."

The only way they were able to get the sound they wanted, or rather, needed for an Audio Research product, they had to start from scratch. The usual disclaimers about show conditions apply, but if the 650 sounds as good at home as it did in Las Vegas, this is an amp to be reckoned with. I believe that Dave said the new amp would go for $7995.

The system also had an up-to-date version of the classic Well Tempered turntable and arm, the epitome of clever engineering. This version had the arm attached to what appeared to be an actual golf ball, which was partially submerged in damping fluid, instead of the expected paddle assembly. I wonder if Surlyn covers sound different than balata, and what effect different dimple patterns might make. I've seen Well Tempered systems described as crude, or "Rube Goldberg" designs. I prefer the term "brilliant" although, I'll confess, the golf ball is a bit much.

The WT fed ARC's two newest front end components, the Reference 2 phono stage and Reference 5 line stage. On the digital side of the rack, the system had ARC's workhorse CDS disc player-transport, which sounded quite good in its own right. I contemplated the system for a few minutes and being an analog guy, the inescapable conclusion was that I need both the Ref Phono 2 and Ref Line 5. Plus, after three days of the show, $12k for each sounded pretty reasonable. I'm sure that Trish wouldn't mind...or is it possible that I've been in Vegas a little too long?

cod's picture

I am 99% certain this amp id the DS-450 (not 650) and the DS stands for Dynamic Series which so far consists of the DSi200 (integrated) and DS-450 (pwr amp). Yes they are Class-D, but as Dave Gordon comments, they are all arc design & built circuits, using arc parts (not off the shelf modules) and are ANALOG, not digital, controlled switching... I've had a DSi200 for 3 weeks now and it is just settling in. I venture to say it will more than hold its own against other $6 ~ $7k integrateds. It is resolving, musical and dynamic.

Stephen Scharf's picture

The golf ball is a way for the original inventor of the Well-Tempered to make this TT and get around IP owned by Stanalog.

Bill's picture

The two questions that come to mind are how this amp will do with low impedence speakers that typically play with class D amps (like sub-3 ohm Apogees) and whether ARC will (sadly) resort to fan cooling as they do on several of their other amps.I am truly curious to see if ARC has captured any of the magic from their tubed products…

Mike Pranka/TOFFCO's picture

Mr. Scharf is mistaken. William Firebaugh, inventor of the WTL turntables, owns the trademark and designs. The use of a golfball as a tone arm pivot in the current design is an ingenious solution to the requirement for an easily obtainable small sphere and nothing else. Stanalog, such as it is, owns nothing with respect to WTL designs or trademarks. It was determined by WTL that under the circumstances, litigation would be a distraction and serve no useful purpose.