Power Amplifier Reviews

Naturally, the folks at Anthem were less than pleased and more than a bit confused about what was going on. They insisted that two of their field reps be allowed to visit and listen for themselves. I happily complied. They arrived a couple of days later, reference CDs in hand. Down to my two-channel room we went.

Guess what? They heard what I heard, not what they were expecting to hear. I swapped out their pair of the Statement M1s for some very expensive Class A/B amps I had under review, and the three of us joyfully listened to their CDs and my vinyl for a couple of hours. But they were mystified about why the M1s didn’t sound as they thought they should and asked if I’d be willing to listen to a different pair they’d been auditioning with great success at dealers around the country.

A few days later, said pair arrived in a flight case, and guess what? They sounded much better. Bass was no longer an indistinct blob, completely lacking in transient definition. Midbass and lower midrange were far better integrated and coherent. The midrange was no longer opaque.

The sound cohered tonally and rhythmically. The amps made musical sense.

Compared to the first five M1s, the casework on the second samples looked different, and I wondered if these were from a different production run. I also wondered whether or not some parts swapping had occurred between runs that might account for the sonic differences.

While these two Class D amps were not what I’d want to live with in my two-channel room (nor were a pair of very expensive Class Ds from another brand I subsequently reviewed for Stereophile), at least I understood why they were put into production and what positive qualities they offered. I stayed up late into the night enjoying what they did very well, which included production of three-dimensional space the first pair didn’t at all manage.

Let’s Call the Whole Thing On
A few months later, I agreed to start over again with another five M1s, brought over by one of the reps who told me, to my surprise, that Anthem had discovered nothing wrong with the first five. These new amps, he told me, like the other pair I’d most recently heard, were just very well broken in. While the engineers didn’t believe in break-in, he did.

Now, was that covering up for a damning discovery of a parts swap at the factory? I don’t know, but if you’d been here and had heard all of this instead of reading about it—assuming the only difference really was break-in time—you’d become a break-in believer if you previously weren’t.

Like the other five, this quintet was poppingly powerful and super-dynamic. Unless you live in a stadium, you’re not likely to ever tax these amps, which, because of their power, exude an effortlessness that only virtually unlimited power seems to produce.

The bottom end of the first five M1s was powerful but lacking in textural subtlety, nuance, and transient clarity, and exuded an undefined rubbery quality. But the second five produced a far superior foundation with the kind of tight, deep, super-controlled bass thrust for which Class D amps are best known. You’ll absolutely love the bottom end these amps produce.

Also, unlike the first five M1s, which were watery and indistinct in the midbass and lower midrange—producing some of the most objectionable recorded piano sound I’ve ever experienced—the second five integrated the bottom and midbass well.

This became obvious when I re-listened to Analogue Productions’ SACD reissue of The Nat King Cole Story, a superb recording with a warm and spacious sound produced in 1960 at Capitol’s justly famous Hollywood Studio. With my original M1 samples, it sounded positively awful, but now it was completely enjoyable and in line with my expectations.

Here’s why: Since the SACD consists of then modern rerecordings of Nat’s greatest tunes (some originally dating from the shellac era) the producers chose not to jar listeners familiar with the originals. So they begin with much improved but slightly old-fashioned-sounding recordings and only by around track seven do they break out in full-dynamic- and frequency-response high fidelity.

The openers, including “Straighten Up and Fly Right,” “Sweet Lorraine,” and “It’s Only a Paper Moon,” are a bit warm and old-fashioned-sounding, with a slightly soft double bass, a mellow hollow-bodied electric guitar, and a slight roll-off to the top end of Cole’s piano, behind which is a bit of Capitol’s famous echo cham-ber. Above it all is the oh-so-mellow Cole.

All of this musical activity takes place in the region where the first five amps sounded absolutely flummoxed. So what should have been distinct, well-separated instruments (behind which tracks the reverb) was a musically indistinct mélange of sonic mud. You could barely distinguish among the instruments. Struggling to stand out from within that thick, rubbery foundation was Cole’s voice, which had little of its round, liquid, mellow tonality or its physical form.

The second five amplifiers easily passed the test on these very familiar tracks. The instruments were distinct and well separated above the reverb, and Cole’s voice was physically distinct, properly sized, and tonally round and mellow. This time the music and the recording made sense. The bottom-end foundation of the second set of amps was as sensational as one would expect from powerful, well-designed Class D amplifiers, and the overall top-to-bottom sound was tonally coherent and spatially well organized.

However, like the first five amps, the second five’s top end, while attractively smooth, was less than fully expressed and somewhat reticent, which is how every Class D amp I’ve ever heard has sounded—perhaps not surprising given the heavy filtering necessary to remove the square wave carrier.

High-frequency transients—cymbals, bells, vocal sibilants, the piano’s top registers—lacked the glistening sharp attack and shimmer heard live. The expected air and bloom heard on familiar recordings were in short supply.

Combine those qualities with the M1’s suppressed sustain and seriously diminished decay, and you’re left with a dramatic, cushiony clarity that can be enticing—especially if you’re mostly used to middling, somewhat sizzly sounding Class A/B amps that retain the qualities of superior sustain and adequate decay. Once you take away the sizzle artifacts and the record’s natural shimmer and decay, you get a kind of listening ease and impressive image solidity. There’s a sense of hearing with unforced ease into heretofore covered detail.

When I re-watched Scorsese’s Shine a Light Rolling Stones documentary on Blu-ray, it was as if I was hearing it for the first time. The amps smoothly and dramatically redefined Mick Jagger’s vocals and beautifully organized and laid bare Ronnie Wood and Keith Richards’ rhythm guitar lines—textures, harmonics, and swagger. But the sense of the hall had gone missing, and Charlie Watts’ cymbals were suppressed to the point of being barely audible.

Handclaps, especially those mixed to the surround channels, were ultra-clear but might as well have been recorded in a small, dry room, not in a concert hall. The sense of the Beacon Theater’s acoustic bubble that five speakers can produce was seriously compromised.

This all raises an interesting question: Are air and bloom and that familiar cymbal sizzle really just artifacts of Class A/B amplification? You decide, but I don’t think so. Proceed with caution before you mistake detail laid bare by omission with genuine revelation of detail.

Listening to Beck’s superbly recorded Sea Change, via either the surround sound SACD or Mobile Fidelity gold CD, was almost disorienting. This airy, all-analog production lost most of its shimmering atmosphere and transient and timbral delicacy. With those in short supply, all of the individual elements used to create the atmosphere were effortlessly revealed, but at what cost? What’s really the point?

Conclusion
Anthem’s Statement M1 amp is a technological tour de force that outputs an enormous amount of power from what seems to be an impossibly small and lightweight package. It appears to be beautifully built, and $3,500 for 1,000/2,000 watts is a bargain in the world of high-performance audio. If you’ve got a big home theater space to fill and speakers that require a great deal of power, the Anthem M1s are certainly worth considering (though the cost of five of these adds up quickly).

In my listening experience, Class D amplification produces sonics that are fundamentally different than what Class A or Class A/B amplification delivers. So before you buy, listen very carefully, especially to the top octaves and the atmospheric cues on familiar music and movies. Pay particular attention beyond your immediate reaction to instrumental attack, and focus instead on the flow of the sustain and the quality and length of the decay. If you still love what you hear, don’t pay any attention to me.