Integrated Amp Reviews

Jim White seems of like mind when he states, in the manual, "Although proprietary RFI (radio-frequency interference) filtering is built into the Mimas, in some situations an AC power-line filter may provide additional sonic benefits." My Niagara 5000 seemed a good choice since, when AQ's designer Garth Powell was developing the Niagara, he tested it with an Aesthetix Atlas power amp, among other equipment. I listened to the Mimas plugged directly into the wall, and then with AC conditioned by the Niagara 5000. Through the AudioQuest I heard a smoother top and tighter bass.

One of the reasons I invite local audiophiles to join me for listening sessions is that they invariably break me out of my classical ghetto with some very different music. A few weeks after I began listening to the Mimas, Port Townsend's Peter Schwartzman came over and proposed that we stream "John Taylor's Month Away" from King Creosote and Jon Hopkins's Diamond Mine (16/44.1 FLAC, Deep Six/Tidal/Qobuz). This lovely track is ideal for evaluating gear. It begins with an emotionally evocative man's voice, progressively backed by guitar and what sounds like a harmonium, a very deep bass rumble, and layered women's voices—then segues into a long, ambient, room-filling, New Age–ish postlude in which sounds of water and birds are layered with synthesizer and female voice.

I first listened to this track with the Mimas plugged into the AudioQuest Niagara 5000. When we switched to wall power, the recording lost some of its arresting ambience, the bass was less clear, and the sense of total immersion at the end was so diminished that the track basically lost its magic. After repeating this comparison with several other tracks, and noting how the Niagara 5000 helped bring out natural color contrasts and details, I stuck with the Niagara 5000—save when, later, I schlepped the Mimas to the house of my friend Gary Forbes, a musician and physician, to hear how it would fare in a system closer to the Mimas's price range (see below).

Opening the ears
Using the Mimas as an integrated amplifier to revisit Paul Lewis playing the first movement, Allegro ma non troppo, of Schubert's Piano Sonata in B, D.547 (24/96 WAV, Harmonia Mundi HMM 902324), I found the sound appealingly musical and involving with realistically round piano notes. As Schubert's music tugged at my heart, I noted the lovely liquid ringing of the piano's high notes and the beauty of the sound overall. But the music lacked transparency and the space between notes was less silent than I'm used to.

Next, I checked out the Mimas's ability to reproduce vibrant tonal colors by listening to two recordings of chamber music by the master colorist Debussy. The sound of his Cello Sonata, performed by cellist Edgar Moreau and pianist Bertrand Chamayou (24/96 WAV, Erato 565142) was not as deep and rich as I know it can be, with tonal colors that were muted. The period instruments of Jean-Guihen Queyras and Javier Perianes performing the same work (24/96 WAV, Harmonia Mundi HMM 902303) sounded extremely natural, with a lovely glow. But with both, I felt I was listening to a recording rather than the sound of real instruments vibrating in space. The difference lay in the slight gauze thrown over the soundstage. Even with the system fully settled in, I was never able to close my eyes and say, "Yes, I feel as though I'm listening to this music in the actual recording venue." It always felt one step removed.

Ten days later, when Peter visited, we began with my old standby: Iván Fischer and the Budapest Festival Orchestra's recording of Mahler's Symphony 3 (DSD128, Channel Classics CCSA 38817/NativeDSD). The beginning of the first movement has blaring horns, pounding percussion, tinkly triangles, and silken strings, all of which soon transition from militant cries of alarm to the sweet sounds of spring. We also listened to the first of Berg's Three Pieces for Orchestra, "Praeludium," in Michael Tilson Thomas and the San Francisco Symphony's highly detailed, low-range–rich, wallop-packing recording (24/192 WAV, SFS Media SFS0070). We then chose "Your Heart Is as Black as Night," from Melody Gardot's My One and Only Thrill (CD, Verve B0012563-02), and ended with "John Taylor's Month Away."

After that, I listened to the same tracks again to grok the sound of the Mimas functioning solely as a preamp, with the Progressions handling amplification, and then compared this with the sound of my reference system. With all four tracks, my impressions were consistent.

The first thing that stood out was the excellence of the Mimas's bass. I'd made a few changes in cables, equipment supports, and power conditioning since reviewing Verity Audio's Monsalvat Amp-60 stereo power amplifier ($58,000) for the May 2019 issue, but I'm 95% certain the Aesthetix Mimas did a better job of handling the Wilson Alexia 2s' impedance dip in the bass. Yes, the D'Agostino Progression monoblocks ($38,000/pair) produce even more bass, but for an integrated amplifier that costs less than a fifth the Progressions' price, the Mimas fared very well. The pounding bass drums in Mahler's Third shook my space and made a substantial mark in the Berg. There was nothing sluggish about the sound of this integrated amplifier.

When I switched from the Aesthetix as a full-functioning integrated to only using its tubed preamp section, highs grew a bit too bright, colors gained in vividness, transparency, detail, and three-dimensionality improved markedly. The lovely warmth and glow often associated with tubes intensified. So did the emotional impact of the music.

The track that proved most revealing was "John Taylor's Month Away." When Peter and I first heard it through the Mimas, I hadn't realized that one of its layered sound effects is created by women singing in harmony. Nor was Peter clear about the source of sounds that we later suspected were made with a harmonium. We were both still taken with the music, but some of the clarity we'd come to expect from my system was absent. As soon as I switched to the Mimas's preamp section, with the Progressions doing the amplifying, solo voice sounded lovely, and the guitar ideally mellow. More color and three-dimensionality emerged, especially in this track's final minutes. Most important, feelings of sadness and empathy captured in the singer's voice received a major boost.

The brightness I'd heard through the Mimas's preamp section vanished when I removed the integrated entirely from the signal chain and fed the Rossini DAC directly into the D'Agostino Progressions. The extra warmth I'd heard in the sound of King Creosote's guitar was replaced by a natural resonance to its body. At one point in the song's first half, when the accompaniment is minimal, the pristine silence that emerged lent the performance a hallowed feel. For the first time, I realized that the low, steady pulse in part of this track is intended to resemble a heartbeat.

In Gary's room
I packed up the Mimas, took it along with me to the living room of my friend Gary Forbes, and plugged it into his system: Immedia RPM-1 turntable with SME 309 tonearm and Lyra Delos cartridge, EAR 834P phono stage, Avalon Acoustics Arcus loudspeakers, nondescript wiring—save for the single power cord and pair of interconnects, all Nordost Odin 2s, I'd brought over to provide some sonic consistency with my own system (and which Gary asks to borrow whenever I'm not using them). The Mimas replaced Gary's older VTL TP2.1 preamplifier and ST-150 power amp.

After the session, Gary sent me a note. I'll quote a few of his comments in much the same way that advertisers often use comments from reviewers: "I...have never heard it artic- ulated so forcefully and tunefully." "I was able to hear deeper into the recording, with lifelike image size." "I heard more body than head. RT's searingly beautiful solo...floated well beyond the speaker's confines." "Listening . . . through the Mimas was like enjoying a vanilla-bean affogato on a summer afternoon—sweet, refreshing, and ready for another."

All of which leads me to say...
When I used the Aesthetix Audio Mimas as a full-functioning integrated amplifier, the strengths of its tubed preamp stage and FET power stage seemed to balance each other out, delivering gratifyingly neutral and flowing full-range sound whose beauty extended through its excellent bass, convincing pace and drive, and delightful touch of radiance. When I used the Mimas solely as a preamp, its sound was brighter and warmer, with increases in transparency, color saturation, three-dimensionality, and the glow often associated with tubed products. In both cases, musical flow, hard-hitting bass, and tonal beauty together drew the Mimas's bottom line.

Reviewing a piece of audio equipment in the context of a much more expensive system runs the risk of emphasizing its shortcomings; well-chosen, more expensive components that are synergistically matched certainly should sound better. Nonetheless, I was delighted by how fine the Mimas sounded in my reference system, and how well it fared in another system with more comparably priced equipment. While I may have wished for more clarity and silence between notes—whether it was Miles Davis or Debussy or Whistler's Mother who said, "Music exists in the space between the notes," it's a truth that has always spoken to me—the Mimas came across as an anything-but-lightweight baby that sang out strongly and packed a mean punch while glowing like a champion. There is something quite special about its sound that deserves a strong recommendation, and that will surely win the hearts of many discriminating audiophiles.