Analog Sources: Linn Sondek LP12 turntable with Lingo power supply & Ittok tonearm, Spectral MC cartridge; Day-Sequerra 25th Anniversary FM Reference FM tuner.
Digital Sources: Bryston BCD-1 CD player, BDP-3 media player with IAD soundboard & Glider MPD Control, BDA-3 DAC, Oppo digital BPD-103 universal BD player; Lenovo P50 ThinkPad computer running Windows 10 Pro (64-bit), Bryston Windows USB driver; JRiver Media Center 23; Roon Core v.1.4 (build 300) stable (64-bit).
Preamplification: Bryston TP-2 30 step-up transformer; Sutherland…
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Sidebar 2: Associated Equipment
Sidebar 3: Using the MartinLogan Dynamo 800X with an External Crossover
I used a JL Audio CR-1 external electronic crossover because its high-pass filter could be used to protect the electrostatic panels of my Quad ESL-989 speakers from deep-bass pulses. To do this, I connected the line-level output of my Bryston BP-173 preamplifier to the input of a JLA CR-1 with balanced interconnects. Additional balanced interconnects were run from the CR-1's high-pass outputs to the Mark Levinson No.534 power amplifier I used to drive the Quads.
The CR-1's high-pass filter was set to 70Hz/24dB…
Friday, February 1, 2–5pm, and Saturday, February 2, 1–5pm, Big Kids Toys AV (1413 Garland Drive, Greensboro, NC 27408) is holding listening sessions. Products being showcased will include Luxman's L-505uXii integrated amplifier and new PD-151 turntable, as well as loudspeakers from Triangle, including the Magellan Cello, and the Esprit Australe EZ and Esprit Titus EZ.
Special guests will include Jeff Sigmund of Luxman America, and Frank Gazzo, of Triangle Loudspeakers, as well as Parke Puterbaugh, former senior editor of Rolling Stone magazine, who will join the discussions and…
"The sound was to die for," I wrote shortly before my resurrection. I was taking notes about the sound of CH Precision's D1 SACD and CD Drive (now $38,000) and C1 D/A Controller (base price $32,000), in the demo room of Michael Woods's Elite Audio Systems, at the California Audio Show, just three months after the 2015 edition of the Munich High End show. CH Precision's L1 dual-mono, solid-state preamplifier (now $58,000), M1 dual-mono power amp ($104,000), and X1 external power supply ($17,000) had helped deliver "fantastic sound."
When I first encountered CH Precision gear, in Gideon…
Pasche told me that at audio shows in Hong Kong and Shanghai, where the I1 and A1.5 amplifiers were paired with Wilson Audio Alexia 2 speakers, exhibitors went with either 0% or 20% global feedback. In Nordost's room at RMAF 2018, in which YG Acoustics Sonja 2.2 speakers were biamped by driving the bass with the I1 and the mids and highs with CH's flagship M1 power amp, a combination of 0% global and 100% local feedback was used. After some experimentation, I found that, with my own Alexia 2s and Nordost Odin 2 speaker cables, 0% global and 100% local feedback delivered the fullest, most…
Although neither manual nor website offers instruction in how to operate the Control app, it's extremely easy to use once someone's shown you how. (Bless you, Ralph Sorrentino.) Whenever I wanted to reconfigure the I1 to connect an external clock, switch between the I1's internal DAC and my Rossini DAC, or activate volume bypass to let the Rossini control volume, change inputs, etc., I grabbed the Android tablet and succeeded, without pain.
Thankfully, the manual does tell you exactly what the buttons on the remote do. While I mainly used the remote to control volume, it also lets you…
At one point, after a short break, we forgot which DAC we'd last listened to. When we started playing music through the I1's DAC, I discovered that the all-important Ethernet link was still connected to the Rossini. How could music be playing without a connection? That's when I realized that the MacBook Pro was set to wireless operation. When Raphael Pasche and I had set everything up weeks before, neither of us had realized that the music was actually streaming wirelessly. Since wireless transmission potentially compromises sound quality, every digital listening test I'd conducted up to…
Sidebar 1: Specifications
Description: Solid-state, class-AB integrated amplifier with DAC. Digital inputs: AES/EBU, S/PDIF, & TosLink to 24-bit/192kHz & DSD64 via DoP; CH-Link to 32/768 & native DSD128; optional Ethernet via UPnP/DNLA compatible source & optional USB to 24/384 & DSD 128. Optional analog inputs: balanced (XLR); single-ended (RCA, BNC); phono MC, virtual ground input. Input impedance: balanced (XLR), 94k ohms or 600 ohms; single-ended (RCA, BNC), 47k ohms or 300 ohms; phono MC, <0.1 ohm. Analog outputs: balanced (XLR), 4V RMS; 1 pair speaker binding…
Sidebar 2: Associated Equipment
Digital Sources: dCS Rossini DAC & Scarlatti clock; Apple MacBook Pro computer with Intel i7, SSD, 8GB RAM; Intel NUC7i7BNH with 8GB RAM, 128GB SSD running Roon; Link-sys routers with two sets TP-Link Gigabit Ethernet media converters plus multimode duplex fiber-optic cables, Small Green Computer linear power supply; external hard drives, USB sticks, iPad Pro.
Power Amplifiers: Dan D'Agostino Master Systems Progression monoblocks.
Loudspeakers: Wilson Audio Specialties Alexia 2.
Cables: Digital: AudioQuest Diamond (Ethernet), Wireworld…
Sidebar 3: Measurements
I measured the CH Precision I1 Universal amplifier with my Audio Precision SYS2722 system (see the January 2008 "As We See It"). Before performing any testing, I connected the amplifier's Ethernet port to my network, then ran it at one-third power into 8 ohms. At the end of that period its top panel was warm, at 107.8°F (42.1°C), and the front-panel display indicated that the internal temperature was 63°C (145.4°F). (This panel is very useful—as well as temperature, it indicates volume, the input settings, and when the amplifier is clipping. It also allows the menu…