Moscode 401HR Tube Hybrid Stereo Amplifier

An audio classic, revised and updated.

Consistent with my initial reservations about the amps’ power, I ran two of them in biamp mode on the Magnepan 1.6s. Upon inserting them, I rather nonchalantly turned back toward the listening chair, but halfway there I almost suffered whiplash as I turned around, mouth agape, at the gale-force sheets of sound emanating from the speakers. I had always enjoyed the highly touted Parasound JC-1s on the 1.6s, but this was sound of a different order. Cymbal rim-shots exploded with ferocity, while the saxophones took on a breathy and palpable character they simply hadn’t had before. The Moscodes revealed much more clearly the propulsive dynamic character of the Convergent Audio Technology preamplifier, making the JC-1s by contrast sound somewhat veiled and demure in character, which was far from what I had expected.

Did timbral accuracy suffer a little bit? Certainly. But the Moscodes lowered the noise floor and peered further into the recesses of the soundstage than the JC-1s. There was simply a feeling of drive and dynamism, an emotional connection that I had never experienced with the 1.6s. The same characteristics were even more amply displayed in running the Moscodes full-range on the big 20.1s, whose far more complex three-way crossover presents higher current demands than the 1.6s. On Wynton Marsalis’ new album Live At the House of Tribes [Blue Note] his trumpet leapt out of the speaker and every microtone, as Marsalis half-keys his trumpet to moan, slur, and soar through glissandos, was captured with remarkable fidelity and presence. The imaging of the amps was quite good, but not stellar. Once again, while the amp doesn’t commit the sin of blurring images, it focuses more on presenting a larger picture rather than spotlighting performers.

The power supply has clearly been carefully regulated. This shows up not only in the unconditional stability of the amp, which never loses its composure no matter how demanding the music, but also in the low noise floor that is as apparent on the 20.1s as it is on the 1.6s. Indeed, the weight of the hall almost comes through physically with the Moscode; on one disc what I think must have been the air-conditioning system running came through loud and clear, too, desired or not. And no matter how hard I tried to drive the amp into overload, it only became warm, not hot, to the touch. It’s hard to believe that it couldn’t handle the most punishing speaker load.

Despite its raw power, however, the amplifier did display one weakness: deep bass control. Ironically, since Kaye features a picture of himself playing the bass on the first page of the manual and touts the amplifier’s supposed grip on low frequencies, the Moscode’s performance here is not as iron-fisted as it might be. It is, in fact, overripe, tubby, and not, dare it be said, the last word in extension, either. On the Kharma Midi-Exquisites, which are a mite polite in the bass, the Moscode’s overly voluptuous low end was not detectable and, if anything, fleshed out the speaker. But on the Thiel 1.6s and both sets of Magnepans, the bass did not match the standard set by the midrange and treble. The Parasound JC-1s and the Classé Omega monoblocks both displayed better tautness and resolution down in the nether regions, which is what one would expect from solid-state.

Did the Moscode amp surpass the Classé Omega and Omicron monoblocks, which cost at least four times as much? No, it did not. The Moscode is not as pure and detailed. But what it conveys, and what no purely solid-state amplifier will perhaps ever fully achieve, is the visceral excitement and palpability of a high-powered hybrid or fully tubed unit. Maybe it was the translucent blue light emanating from the glass windows on the front of the amp, but I found this diminutive amp rather bewitching. If you’re considering an amp around $5000 or even double that, you would be remiss not to consider the Moscode. You can spend a lot more for a lot less than the Moscode. It will be awfully hard to break the spell it casts. &