Columns Retired Columns & Blogs |
John, what kind of load resistors do you use in testing? Obviously, they can take way more than 1kW per channel.
If I then didn't hear much of a difference, that was because the main source of noise turned out to be the rusted-out mess of a 35-kilovolt-amp transformer that fed our house and four others. While PUD No.1 promisedbless Kevin Street's hearta new and significantly more powerful 50kVA transformer, all they could say was "within the month."
As fate would have it, installation day arrived soon enough, after which the sound of my system was noticeably smoother and less zingy.
With so much less noise to contend with, I finally felt comfortable with Udo Besser's request to plug the Ovation MA8.2s directly into the wall rather than into my Nordost QB8 eight-outlet power distributor. (Because the Nordost QB8 is designed to be non-current limiting, I'd always plugged my reference Pass Labs XA200.8s into it to minimize noise.) At that point, given all the changes to my power setup, I no longer had any idea what the Passes sounded like, regardless of what they were plugged into.
Without a reference, I was lost at sea (not that anyone would want to be lost at sea chained to a 50kVA transformer). I had to start my listening from scratch, on a new, level playing field that included plugging the AVM Ovation MA 8.2s directly into the wall.
Listening
As I played CDs, SACDs, and high-resolution files, the first thing that struck me about the MA8.2s was how clean, clear, and neutral they sounded. Listening to "Bahia Com H" and "Insensatez," from Entre Amigos, by bossa nova singer Rosa Passos and double bassist Ron Carter (CD, Chesky JD247), left me marveling at the transparency of the sound, as well as the ability to hear the different acoustic envelopes around Passos's voice, Carter's bass, Lula Galvão's guitar, and Paulinho Braga's percussion. I felt I could hear the natural beauty of each musician's "voice," without added warmth or sweetness. The AMVs' control of the bass was exemplary.
I listened to soprano Eileen Farrell's recording of Amelia's "Come in quest' ora bruna" (How in this morning light), from Verdi's Simon Boccanegra, with Max Rudolf conducting the Columbia Symphony Orchestra, from Eileen Farrell Sings Verdi (CD, Columbia Masterworks 62358). I was surprised to hear that her voice seemed a bit cut-out and superimposed on the sound of the orchestra. I play this track often, and feel that my Pass amps do a better job of blending voice and orchestrawhich is not to deny that the AVM MA8.2s' presentation of such recordings may be ultimately more accurate. Some of the cello richness I usually hear was missing in action, and orchestral textures were less dense.
Nonetheless, when the orchestra emits a sudden chord of dread as Amelia sings, of her long-dead mother, "Memories of the dark and cruel night / When the dying woman exclaimed, 'May Heaven watch over you,'" the accompaniment sounded more focused, and had far more emotional impact than I'm used to. After umpteen listens, this was the first time I was actually startled by that chord, and by what it represents emotionally. I was also thrilled anew by the beauty of Farrell's voice. Such "like new" experiences count for a lot in my book.
While the voice of soprano Elly Ameling sounded extremely clear in several Schubert songs with piano accompaniment from her The Art of Elly Ameling (4 CDs, Philips 473 451-2), in "Die Sterne" (The Stars), the sound was, again, a bit more spare than I'm used to. This is one of those earlier stereo recordings for which the engineers divided the sounds of piano (left) and voice (right), the latter reverberating a lot in space. There was just a bit too much dead space between the two for the presentation to convince. But the beauty of Ameling's voice was to die for.
"What a gorgeous sense of space, with such beautiful tonalities," I wrote in my listening notes upon playing, through the AVM amps, John Atkinson's recording of the male vocal ensemble Cantus performing Eric Whitacre's Lux Aurumque, from the group's While You Are Alive (CD, Cantus CTS-1208). "These amps really capture how these voices sound in this acoustic." Dynamic swells were convincing, and all vocal ranges were perfectly balanced, the high tenors floating beautifully above the rest.
Antonio Bertali's (16051669) Ciaconna for Violin, Keyboard, and Chittarrone, from violinist Rachel Podger's Perla Barocca: Early Italian Masterpieces (SACD/CD, Channel Classics 36014), was equally captivating. As Podger and the other musicians went to town, her piquant playing was depicted with greater veracity and clarity than I'd ever heard on my system. A major wow experience.
I may think the music of Mason Bates, despite its hard-to-resist techno/dance beats, more silly than profound. But Chicago, 2012a movement from Michael Tilson Thomas and the San Francisco Symphony's recording of his Alternative Energy (SACD/CD, SFS Media) that includes the recorded sounds of particles in a Fermi accelerator zooming across an exceptionally deep, wide soundstageis loads of fun. While I wished for even stronger bass, and wanted the lower midrange and bass sounds to expand spatially, as they would in a live concert, there was no denying that the opening crash of glockenspiel, brass, and timpani was startling, and the subsequent deep rumblings of timpani and accelerator exciting. Percussive attacks were as tight as can be. As for the sense of depth and space, it was supreme.
Speaking of percussion, listening to musical snippets of Channel Classics SACD/CDs of recordings of Mahler's Symphonies 2 and 9 by Iván Fischer and the Budapest Festival Orchestra (23506 and 36115), and another disc from that label, Homenaje a Revueltas (SACD, Channel Classic CCS SA 21104), devoted to the music of Silvestre Revueltas, confirmed that while the bass could have been weightier, its control was excellent, with virtually no boom. The MA8.2s were very, very fast. For the first time, I could hear individual notes in fast timpani rolls cleanly articulatedsomething I can't hear with my Pass amps. I could also listen deep into the vast violin sections of the Mahler works and pick out contributions from individual players.
The biggest percussive ear-opener came when I played "Black on White Paper," from Zen Widow's Screaming in Daytime (Makes Men Forget) (CD, pfMentum PFMCD 069), which producer Joe Harley recorded live to two-track analog. The brutality of this take-no-prisoners music showcases Garth Powell's slamming percussion and Wadada Leo Smith's bright, eloquent trumpet, and will likely send your pet kitty flying in fright. The Ovation MA8.2s nailed it all, from Gianni Gebbia's breathy alto saxophone to the weird rhythms of Powell's precision-perfect attacks. Even the violence of Matthew Goodheart's piano attacks was replicated to perfection. The effect was sensational.
After finishing my formal listening evaluations, I re-experienced the MA8.2s' strengths when I reviewed, for Stereophile.com, Craig Hella Johnson conducting the choir Conspirare in Johnson's requiem, Considering Matthew Shepard (SACD/CD, Harmonia Mundi 807638). While my focus was on the music rather than on sound quality per se, I couldn't help noting that the loveliness of the women's voices, the expert contributions of several soloists, and the superb percussive and dynamic contrasts were touching me deeply. That I found the composition itself far too sentimental and saccharine was made possible, in part, by the AVM monoblocks, which reached into the music's emotional center and shared it with me without editorializing on it.
Conclusions
If your priorities in sound include precision, speed of attack, exciting dynamic contrasts, a truthful presentation, and tonal neutrality that allows a recording's inherent beauty to sing, you owe AVM's Ovation MA8.2 monoblocks a long listen. At $29,990/pair, cheap they ain't. But if you can find a way to let them sing in your system, you will, in many ways, feel rich indeed. Most highly recommended.
John, what kind of load resistors do you use in testing? Obviously, they can take way more than 1kW per channel.
John, what kind of load resistors do you use in testing?
For testing high-power amps I use an array of four non-inductively wound 8 ohm resistors, each with its own heatsink, mounted on an aluminum plate. They are connected in series-parallel to give a combined load of 8 ohms.
Obviously, they can take way more than 1kW per channel.
Only in the short term.
John Atkinson
Editor, Stereophile
Hi JA
In figure 8 there is an enharmonic peak at 180 hertz
Do you know what this is....power supply multiple ?