For years, I’ve bought into the conventional wisdom about Magnepans: mating low powered tubes and planars is like trying to unite oil and water. But thanks to Nagra and Verity Audio’s distributor John Quick I had the chance to demo a pair of Nagra VPA amplifiers based on the legendary 845 tube, a worthy, perhaps the only true, rival of the 300B. Quick had sent me the Nagra VPA to use on Verity’s flagship Lohengrin loudspeaker, which I discuss at length in an upcoming issue of the Absolute Sound. On the Lohengrin, the VPA had the effect of making the loudspeaker disappear into the ether—in the best sense of the word. Instruments simply hovered in space, whizzed in and out, leaving me transfixed with admiration. But I suppose that’s not entirely unexpected given that the Verity runs at a commendably efficient 95dB.
The Magnepan 20.1 does not. Just look at the size of it in the accompanying pictures. It’s a behemoth. Plus those Gothams down low. So with high power, you can really peel it out with the Magnepans. But it’s hardly the only way to run the 20.1. As I quickly discovered, the Magnepans simply sound glorious when run with the diminutive, 50-watt Nagra. The tonal colors, low level noise floor, resolution of fine level detail, and purity of sound are stunning. Let me be clear: I did not use the VPA to run the bass panel of the Magnepan, a task that it could hardly perform. Instead, I used it to drive the midrange and tweeter in a biamped configuration using a four-chassis, custom tubed crossover designed by Tom Tutay of Transition Audio in Fort Walton Beach, Florida. This relieved the Nagra of having to reproduce any frequencies below 300Hz. The Magnepan also offers an essentially benign 4 ohm resistive load, but its efficiency is estimated at a lowly 86dB.
No, I’m not able to play the Nagra at ear-splitting levels on the Magnepan (I can already hear my colleague Jonathan Valin, who has a commendable distaste excessive sound pressure levels, crying out “Why would you want to!”). Well, I have to admit sometimes I like to crank it up. But overall, the sense of information conveyed by the Nagra means that you don’t really have much of a temptation to turn up the levels. On the contrary, it’s fascinating to hear how much detail appears when you listen softly. The VPA has that crepuscular feel, where reproduced music shades into the most delicate, blissful sound possible—a kind of twilight saga, if you will. As for potent dynamics: the blunt fact is that even when turned up, most music—at least the stuff I listen to—doesn’t seem to demand more than, at most, 30 watts, according to the snazzy needle on the VPA’s faceplate.
Suffice it to say that I’m beguiled, smitten by the Nagra VPA. It’s been around for a decade or so, and was radically upgraded years ago, but to my ears it sounds darned good, even if it’s not the newest kid on the block. And it’s forcing me to take another look at the issue of amplifier power and sonic prowess as well as reexamine some preconceptions about Magnepan loudspeakers. What more can you say than that?