In an extended Skype conversation with Voss and Sebastian Ruhland, a…
search
Accustic Arts of Lauffen, Germany, was founded in 1997 by Fritz Schunk, who sold the company to Hans-Joachim "Jochen" Voss in 2016. Voss's professional background had more to do with sweet spreads than sweet sounds—he spent 20 years doing sales and marketing, including with the Ferrero Group, which produces Nutella—but he happened to own some Accustic Arts components, and as a music-loving consumer with a special fondness for rock, had been in touch with Schunk for many years before the company went up for sale.
It was when I turned to reference files, streams, and CDs that I was able to pinpoint what makes the Accustic Arts Mono II's sound unique. With thanks to friend Peter Schwartzman for leading me to it, I cued up "John Taylor's Month Away" from King Creosote and Jon Hopkins's Diamond Mine (16/44.1 FLAC, Deep Six/Tidal/Qobuz) on Roon. Silences between notes were pristine, as though King Creosote was captured singing softly in the middle of a forest where the wind had ceased and birds had migrated elsewhere. There was something uniquely beautiful and warm about the midrange core of the guitar…
Sidebar 1: Specifications
Description: Solid-state fully balanced class-AB monoblock power amplifier Inputs: 1 unbalanced (RCA), 1 balanced (XLR). Outputs: 2 pairs speaker binding posts. Power output: 300W into 8 ohms (24.8dBW), 500W into 4 ohms (24.0dBW), and 700W into 2 ohms (22.4dBW). Frequency response: 2.6Hz–105kHz, –3dB. Voltage gain: 31dB. Intermodulation distortion: 0.007% at 10W into 4 ohms. Signal/noise: 104dB A-weighted (ref. 6.325V). Damping factor: >300 at 1kHz and 4 ohms. Input impedance: Balanced (XLR): 2 x 20k ohm, Unbalanced (RCA): 100k ohms. Output impedance: <10…
Sidebar 2: Associated Equipment
Digital Sources: dCS Rossini Transport SACD/CD transport & Rossini DAC & Rossini Clock; Intel NUC7i7BNH with 8GB RAM, 128GB SSD, running Roon; Linksys routers with two sets TP-Link gigabit Ethernet media converters plus multimode duplex fiber optic cables; Small Green Computer linear power supply (2) & Small Green Computer 200W Linear Power Supply; external hard drives, SSD USB sticks, iPad Pro.
Power Amplifiers: Dan D'Agostino Master Systems Progression Monos.
Loudspeakers: Wilson Audio Specialties Alexia 2.
Cables: Digital:…
Sidebar 3: Measurements
I performed a full set of measurements on one of the Accustic Arts Mono IIs, S/N M2-1JB1258, using my Audio Precision SYS2722 system (see the January 2008 "As We See It"). I repeated some of the tests on S/N 1259, the sample that Jason Victor Serinus found had developed a hum toward the end of his auditioning. Before doing any testing, I preconditioned the first sample of the Mono II by running it at one-third power into 8 ohms for an hour. At the end of that time the side-mounted heatsinks were hot, at 120.6°F (49.3°C). The top panel was also hot, at 104.1°F (40.…
Manufacturer's Comment
Editor: The lack of performance of the Accustic Arts Mono II power amplifiers was caused by the fact that we unfortunately installed wrong transformers. Instead of using transformers that deliver a voltage of 2 × 54V and 2 × 58V on the secondary side, we installed transformers that deliver a voltage of only 2 × 48V and 2 × 54V on the secondary side. Our final measurement report, which is created for each device that leaves our manufactory, is in agreement with John Atkinson's results. With the right transformers, the Mono II power amplifiers do achieve the values…
Godzilla and I are precisely the same age: We were both born in 1954, Godzilla as an expression of the postwar fears of a nation uniquely aware of the horrors of nuclear armaments, I as an expression of the postwar comfort felt by an American veteran fresh from foreign wars. We both dislike being awakened from our slumber, and we're both unusually handsome.
Like so many Americans of my generation, I love Godzilla—along with Mothra, Rodan, Tobor the 8th Man, Speed Racer, and the Panasonic transistor radio my dad gave me in 1965. During more or less the same stretch of time, Japanese baby…
In time, I got it all sorted. And the good thing about the Uchida/Komura replacement wires is that they're longer than stock—long enough, in fact, that I was able to leave the crossovers outside of the Flamenco enclosures. (Normally, Altec fastened their crossover networks to the speakers' rear panels via the threaded shafts of the treble-level controls that protrude from them—but who has that kind of time?) Happily, the Altec N-1019listenal.-A has (screw type) input terminals installed on its case-work, rather than input leads that need to be soldered to connectors of some sort; I was…
The Vivaldi—the four-box flagship product from digital audio specialists dCS—is, in my opinion, misnamed. Vivaldi the composer was an asthmatic priest who worked in an orphanage for 30 years and died in poverty. The Vivaldi stack dedicates four separate products to converting into music digital code stored on silver discs (although you can play music—very well I am sure—on just one box, the Vivaldi DAC, footnote 1). Together, those boxes weigh about 148lb and cost some $115,000. The most expensive is the CD/SACD transport; leave that off and you can save 51lb and $42,000.
So why not…
I differ from some of my colleagues, though, in believing that straight-up A/B comparisons can be useful. All but the most subtle changes in the character of sound, I've found, can be discerned in level-matched A/B switching—and this approach can expose common reviewing errors, like mistaking a small difference in volume for a difference in quality. Playing the same passage over and over, switching between (or among) different source components, is an effective way to hear even subtle differences in spatial performance, reverberation tails, and other manifestations of low-level resolution…