Halcro dm88 Reference monoblock power amplifier Page 2
Unplug the dm58s, plug in the dm88s
The system I surrounded the Halcro dm58s and dm88 References with consisted of my VPI HR-X turntable with Lyra Titan cartridge, the EMM SACD stack for digital, Wilson Audio Specialties Sophia loudspeakers, and Halcro's own dm10 full-function preamplifier or Sutherland's PhD phono stage with VTL's TL-7.5 line stage. The cabling varied a bit, but most of the time was Shunyata Research, starting with the wall outlets and ending at the speaker terminals. I supplied the front end and each amplifier with its own power circuit, as suggested by Halcro's rep Philip O'Hanlon, but drew the line at converting my listening room to 240V power.
The dm88s behaved perfectly during their time in my system. They were easy to move around, simple to connect, bulletproof in use, and, wonder of wonders, ran cool to the touch. Just like the dm58s. The dm88, however, has a fourth operational mode and set of input jacks. In addition to the standard balanced and unbalanced Voltage Mode and Current Mode inputs, the dm88 has a Minimal Path input that bypasses a chunk of the amp's circuitry and, Halcro claims, results in a bit less gain but a purer sound. "Purer sound" sounded intriguing, but, slacker that I am, I did the bulk of my listening using the balanced Voltage Mode inputs.
Same as it ever was? The dm88 and dm58
To establish a baseline without having to repeat several pages' worth of superlatives, I refer the reader to Paul Bolin's listening impressions of the dm58 in the October 2002 issue: "The dynamics, purity, and total transparency were beyond anything in my prior experience." Check. "Transcendentally neutral." Check. "I was hearing...the unalloyed sound of the music as recorded." Check. Silence, reproduction of the tiniest detail, superb soundstaging, "dynamics that mere mortal amps cannot manage"—all were there with the dm88 Reference, as they'd been with the dm58. In fact, with regards to these aspects of their performance—in my system and room—the two amps were all but indistinguishable.
At times I thought the dm88 was a touch more dynamic than the dm58, its transients swinging slightly further toward both ends of the scale of pppp to ffff, but it wasn't a difference I could really get hold of. The sheer scale of their transient performance made it hard to match their levels to those of other amplifiers and then compare them. So establishing a common reference was out. Measuring levels at 1kHz made the Halcros' dynamics too large to comprehend, and balancing things by ear resulted in the Halcro—either Halcro— playing at an average level several dB below the other.
The one area PB didn't really delve into was what I'll call the dm58's tonal richness or tonal density—how well it reproduced the harmonic complexity of a violin or cello, for example, and how this complex mix of tones and characteristics evolved with time. Paul noted that individual instruments sounded lifelike and alive, and that their images were realistically constructed, but such words as rich, sweet, and luscious, and expressions such as woody and resinous, don't appear in his review. He mentioned more than once his feeling that the dm58 sounded bright or forward—then backed up to note the amp's overall neutrality and attribute the impression to the source material.
In my Follow-Up to Paul's review in the February 2006 issue (Vol.29 No.2), I, too, wrestled a bit with my feeling that the dm58 wasn't as tonally rich as the real thing, trying to reconcile it with my sense of the amp's obvious and overwhelming neutrality and purity. When Wilson Audio's John Giolas asked if I preferred the dm58s or VTL's S-400, I chose the latter, though I was hard-pressed to say exactly why. Looking back now at what I wrote, a few phrases jump off the page: the VTL sounded "richer and woodier," its "textures...felt slightly more real," and "there always seemed to be a bit more 'there' there." Tubes vs solid-state, truth vs euphony—I didn't know then, and I still don't.
The reason this question of tonal richness seems important now, and didn't when PB and I were listening to the dm58, is because back then we didn't know any better. Now, thanks to the dm88, I do. I hope that John Atkinson's measurements will shed some light on what the dm88 is doing right that the dm58 didn't, because it was definitely doing something, and that something was most definitely right. Instruments and voices were notably sweet and rich, and luscious without being at all overblown or colored. Each instrument, each note, was an incandescent, ever-changing mix of textures and tones. The dm58 was Kansas, the dm88 Oz.
Whenever I switched from the dm58 to the dm88, just about the time I'd finish writing something like "No, they sound the same after all," I'd start to smile and shake my head. From that point on, my notes would say things like, "Wow, wow, wow! What a great record—no, what a great show! I can hear, see, and feel the performers. I can hear the notes' characteristics evolve and change as they echo around the hall. Just incredible!" An audiophile 45rpm disc? Nope, "Heroin," from Lou Reed's live Rock'n'Roll Animal (LP, RCA AYL1-3664). The realism, and the way the system melded my listening room to the performance and space, were eerie.
I pulled Mitch Ryder's Breakout...!!! (LP, New Voice 2002-S), which I'd listened to through the Simaudio Moon Rocks, the VTL S-400, and the dm58, all in similar systems. It sounded warm and fat through the Moon Rocks, and I noted at the time that the simpler miking techniques of 1966 really did result in "more involving" recordings. With the VTL S-400, the soundstage opened up, most of the warmth went away, and I upgraded my opinion to believing that those few mikes produced a "more honest" recording. The dm58s moved things into the ultraneutral world of HalcroLand, but pointed out that this recording, simple miking technique or not, sounded a bit thin, and that the Simaudio and VTL were adding a bit of harmonic sweetness.
After scribbling down a page of notes about precision, detail in background vocals, fast leading edges, notes stopping and starting precisely, and super-sharp placement of images, I switched to the dm88s and cued up Breakout...!!!'s first track, "Walking the Dog." This time, I didn't even get halfway through writing "No, it sounds the same after all" before I started smiling and tapping my foot. Then it hit me— This must be how it was supposed to sound. This must have been how it sounded when it was recorded.
I tried to find a way to describe this rightness as I worked my way through several listening sessions and stacks of LPs and CDs that I know inside and out. With Rickie Lee Jones' Girl at Her Volcano (LP, Warner Bros. 23805-1B), I tried working with the body and depth her voice had through the dm88s. I searched for ways to explain the more complex layering of tones and the sweet snarl of bent strings in Keith Richards' guitar on Johnnie Johnson's Johnnie B. Bad (CD, Elektra/Nonesuch 61149-2). The brassy blare or soft, subtle breathiness of Miles Davis' trumpet, Mandy Mesplé's vocals filling the hall in Delibes' Lakmé (LP, Seraphim SIC-6082), even the simple warmth and resonance of a solo cello—as in Franz Helmerson's performance of Bach's Suite 2 in D Minor (LP, BIS LP-65)—all were similarly mesmerizing. In each case, I tried to describe the dm88's tonal and textural correctness and the difference it made. In each case, I kept coming back to an overriding sense that This was the way it was really meant to sound.
Just another Halcro?
In 2002, the Halcro dm58 established a level of performance so far beyond its contemporaries that the standards and criteria of the day didn't apply. It was perfect. Only now, four years later, are competitors emerging that can truly be considered alongside the dm58. Between the dm58 and the S-400 specifically, it was essentially a toss-up; though I couldn't pinpoint the difference(s) between them, I ended up preferring the VTL. This suggests that, once other designs begin to approach the dm58's performance in the more obvious ways, the competition moves to the realm of more subtle effects.
The same is true when comparing the dm88 to the dm58. Using old terms of reference, the dm88 is merely an updated dm58/68. I'm told that, in larger rooms or with more demanding loads, the dm88 has better bass definition, or cleaner dynamics, or perhaps even slightly better clarity and precision. In my room and system, however, these aren't apparent—the dm88 simply retains all of the dm58's strengths or perhaps exceeds them slightly. There's a bit more power and a fourth input mode, but in terms of the gross distortions that the dm58 obliterated, there's not much difference between them.
But on the new playing field, where neutrality, precision, speed, clarity, etc., are all givens, the dm88 Reference is as revolutionary as the dm58 was in 2002. It is the best audio component I've heard, and as far beyond its competition, including the dm58, as the latter was beyond its contemporaries. As Paul Bolin said of the dm58, "Whatever its flaws may be, their discovery may have to wait until someone, somewhere, has developed an even better amplifier." If the past is any indication, that someone may, once again, be Bruce Candy.