Analog sources: Garrard 301 turntable in a Box Furniture Co. plinth; Thomas Schick 12" tonearm; Hana Umami Red, Ortofon SPU Classic G, and Zu/Denon DL-103 cartridges.
Digital sources: Sonnet Morpheus DAC; Sonore opticalRendu; Roon Nucleus+; Small Green Computer sonicTransporter i5 server running Roon Core.
Preamplification: Shindo Aurieges preamplifier; Parasound Halo JC 3+ phono preamplifier.
Power amplifiers: Shindo Montille; Line Magnetic LM-845IA; SET amplifier with triode-wired 307A output tubes, built by Oliver Sayes.
Loudspeakers:…
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Sidebar 2: Associated Equipment
Sidebar 3: Measurements
I used my Audio Precision SYS2722 to examine the Jadis JS1 MkV's performance. To minimize the possibility of the analog circuitry picking up noise from the power supply, I placed the supply on the floor, as far away from the processor chassis as the two umbilical cables would allow. The heatsinks on the back of the supply became very hot during testing, their temperature stabilizing at 135.3°F (57.4°C).
The processor's AES3 and optical and coaxial S/PDIF inputs locked to data sampled up to 192kHz. Apple's AudioMIDI utility revealed that the USB inputs…
At noon on a cloudless, ridiculously bright 97° day, John Atkinson and I auditioned Audeze's new-but-not-yet-released CRBN electrostatic headphones. The audition took place at a sneak preview hosted by Audeze's principal, Sankar Thiagasamudram, in a sleeping room at New York's hipster-chic Ace Hotel on 29th Street and Broadway. Décor in this unusual sleeping room included a bathtub with feet, an antique wood ironing board, a vintage Gibson guitar, and a working stereo system with a Music Hall turntable and an assortment of vintage LPs.
On my way there, I was remembering some of my…
One of the best records I have for making this energy-in/energy-out comparison is Roscoe Holcomb/The High Lonesome Sound (Folkways LP FA 2368). On my preferred, simple LP-based sound systems, Roscoe's otherworldly voice and close-miked banjo come out sounding a lot like I imagine they did while the recording was being made. Western Electric engineers called this phenomenon "Mirrophonic": "A True Reproduction of the Original."
Speaking of Western Electric: I recently heard that High Lonesome disc on a 10'-tall, five-way horn-speaker system with a $350k record player. That…
The $50,000, 176lb Accustic Arts AMP V (pronounced Amp Five) is the heaviest, tallest, most powerful, most expensive stereo amplifier to enter my audio system. With rated power of 900Wpc into 8 ohms, 1360Wpc into 4 ohms, and 1500Wpc into 2 ohms, the AMP V, which stands proud at the top of the Accustic Arts amplifier line, surpasses my reference D'Agostino Progression M550's rated power into 4 ohms by 260Wpc (footnote 1).
What, if anything, might those extra 260Wpc—and those extra pounds of transformer and heat-dissipating metal—mean sonically in my moderately sized listening room? I was…
While I usually place equipment supports under components, I decided to skip them in this case to avoid damaging a hand as I struggled to lift a corner of the amp while not tipping over the amp stand. After connecting XLR and speaker cables, I ran two Nordost Odin 2 15-amp power cables from the AMP V to the same AudioQuest Niagara 7000 power conditioner I use with the D'Agostinos and began my journey.
Color and richness to the fore
On Igor Levit's On DSCH (24/96 MQA, Sony 714315), which I reviewed for our December issue, the AMP V's ability to convey the emotion behind the…
Sidebar 1: Specifications
Description: Solid state, dual-mono stereo power amplifier. Inputs: 1 balanced (XLR), 1 pair single-ended (RCA). Outputs: 2 pair WBT binding posts. Input impedance: balanced, 16k ohms; single-ended, 15k ohms. Minimum loudspeaker impedance: 2 ohms. Voltage gain: 30dB. Frequency response: 10Hz–50kHz (+0/–0.5dB) at 10W into 4 ohms. Rated power output at 1% THD+N: 900Wpc into 8 ohms (29.5dBW), 1360Wpc into 4 ohms (28.3dBW), 1500Wpc into 2 ohms (25.8dBW). Zero signal current setting: 300mA. Power supply capacitance: approx. 220,000µF. S/N ratio: 96dBA (ref. 6.325V).…
Sidebar 2: Associated Equipment
Digital sources: dCS Rossini SACD/CD transport, Rossini DAC, and Rossini Clock; Roon Nucleus+ server; Uptone Audio etherRegen with AfterDark Giesemann Emperor Double Crown Master Clock; Small Green Computer Sonore opticalModules (2) and Deluxe opticalModule; Linksys routers (2) and Arris modem, all powered by HDPlex 300 four-component (3) and HDPlex 200 linear power supplies. Apple 2017 iPad Pro and 2017 MacBook Pro with 2.8 GHz Intel i7, SSD, 16GB RAM.
Preamplifier: Dan D'Agostino Momentum HD.
Power amplifiers: Dan D'Agostino Progression M550…
Sidebar 3: Measurements
Usually, when I measure an amplification or digital product, I carry the box down the stairs to my basement, where I have my listening room and test lab. However, the Accustic Arts AMP V was too heavy for me to do this. Instead, I rolled it in its wheeled flightcase into the vestibule outside the listening room, removed the flightcase cover, and left the amplifier sitting in the flightcase (footnote 1) at the top of the small flight of stairs. I then set up my Audio Precision SYS2722 system (see the January 2008 As We See It) with its dedicated PC, my analog and…
Manufacturer's Comments #1
Yesterday, we once again determined the maximum power output of another AMP V at a test setup in our factory. Basic conditions: constant mains voltage of 232V; 1kHz sinewave continuous output: THD+N=1%.
With this, we achieved the following results, with tests carried out in this order:
1: 8 ohms for 20 minutes—max. output: 912W 2: 4 ohms for 15 minutes—max. output: 1408W 3: 1.5 ohms for 5 minutes—max. output 1530W 4: 2 ohms for 5 minutes—max. output 1509W
After this treatment, the AMP V was hot, and it took around 120 minutes for…