Musical Fidelity 750K Supercharger monoblock power amplifier Page 2

Looking back at what I've written, I seem to have concentrated on the 750K's abilities to play loudly and cleanly—which they indeed did. But for all their ability to kick loudspeaker butt, the Musical Fidelity could still do delicacy with aplomb. Robert Plant and Alison Krauss's Raising Sand (CD, Rounder 11661-9075-2) has been in heavy rotation chez Atkinson since I picked it up while killing time at a Starbucks a year ago. The double bass on this disc can be problematic with some amplifier-loudspeaker combinations, as its considerable midbass energy demands an amplifier capable of retaining control of the woofers if the sound is not to degenerate into mud, while at the same time allowing this recording's wealth of midrange detail to emerge unscathed. The bass in Gene Clark's "Polly Come Home" had the appropriate combination of weight and definition, without obscuring Plant and Krauss's mysterious-sounding harmonies as they soared over Marc Ribot's contemplative guitar figurings, all against a richly ambient backdrop.

Again looking back, I see I have avoided mentioning how the Musical Fidelitys coped with complex classical music. They did very well with naturally miked recordings. They allowed, for example, the sense of space Tony Faulkner had captured with Antony Michaelson's performance of the Mozart Clarinet Concerto, with conductor Robert Bailey and the Michaelangelo Chamber Orchestra (SACD, Musical Fidelity MFSACD017), to emerge from the speakers unscathed. And with a hi-rez, 24-bit/96kHz FLAC download of Britten's Simple Symphony, performed by the Trondheimsolistene (originally released on the SACD Divertimenti, 2L 2L50SABD), the joyous sound of the violins never became steely or hard, or too soft or mellow, while the double bass and cellos neither boomed nor sounded too lean.

Only once did the amplifiers' cooling fans turn on. I was playing organist Michael Murray's thunderous performance of Bach's Prelude and Fugue in D (Telarc CD-80088) and reveling in the Revel Salon2s' apparently limitless dynamic range when driven by the Musical Fidelitys. At the end of the track, after the blower noise from the organ on the disc had faded away, I could just hear the much quieter sound of the 750Ks' fans. They never came on at normal listening levels.

While it shared many of the merits of Musical Fidelity's own 750K at half the price, the 550K Supercharger sounded lean in direct comparison with the 750K. Whereas the 750K worked well with every speaker I hooked it up to, the 550K needs to be matched with speakers balanced a little on the fuller-figured side. Significantly, after Cantus producer Erick Lichte had turned in his Follow-Up on the 550K, we spent a weekend together working on the mixes for the next Cantus CD, using the 750Ks to drive Revel Salon2s. "That," he said, pointing to a 750K, "is a very different amplifier from the 550K." Yes it is!

Against my long-term reference amplifier, the Mark Levinson No.33H (150W, $19,900/pair when last available), the Musical Fidelity surprised me by having better-defined, more extended low frequencies. The Levinson sounded somewhat "puddingy" in direct comparison—not at all what I had expected. The Levinson had slightly sweeter mids and highs, but it was a close-run thing. Next up was the Parasound Halo JC 1 (450W, $7000/pair), a long-term favorite of this magazine's review team and of mine. The Parasound had low-frequency slam and definition to match the Musical Fidelity's but was cooler-balanced overall, sounding similar to the 550K, though its highs were smoother.

My auditioning of the Musical Fidelity 750K was interrupted by two weeks spent with the Ayre KX-R preamplifier, reviewed last month by Wes Phillips, along with the Ayre MX-R monoblocks (300Wpc, $18,500/pair) he had used to prepare the review. In direct comparison, the Ayre matched the 750K's slam, bass definition, and soundstaging depth, and offered a slightly sweeter high end. I mean no disrespect to the 750K when I say that the MX-R could be my ultimate amplifier. But the price difference is significant, and I could happily live with the Musical Fidelitys.

Summing Up
Sounding significantly less lean than both the kW and the 550K, the 750K Supercharger is, without a doubt, the best-sounding amplifier I have heard from Musical Fidelity. While I still prefer the Mark Levinson No.33H for ultimate midrange sweetness, the Levinson is outclassed by the 750K in bass solidity, control, and overall dynamics. At $10,000/pair, it is undoubtedly expensive, but its immediate competition is more expensive or less powerful, or both (eg, Ayre's MX-R). Forget the Supercharger nomenclature—this is a power amplifier that can stand on its own feet.

Musical Fidelity Ltd.
US distributor: KEF America
10 Timber Lane
Marlboro, NJ 07746
(732) 683-2356

Btylutki's picture

....for Jamicon Electrolytic Polarized input capacitors! For $10K! Really?