search

Transient Mk.II Asynchronous USB Converter: Digital outputs: S/PDIF via 75 ohm BNC (galvanic isolated), I2S via mini-DIN (Audio Alchemy, Perpetual Technology, Camelot), Differential I2S via HDMI (PS Audio, Wyred4Sound). Sample rates supported: 44.1, 48, 88.2, 96, 176.4, 192kHz, up to 24 bits. Master-clock jitter: <1.0ps. Analog output level: 2V RMS maximum (single-ended RCA). Frequency response: 20Hz–96kHz. THD+noise: –89dB at –1dBFS.
Serial number of unit reviewed: TR3010.
Price: $699.

VDC•5 Mk.II High Current Power Supply: AC Input Voltage:…

Digital Sources: Apple MacBook Pro computer (2.66GHz Intel Core 2 Duo, 4GB RAM, 320GB HDD) running OS 10.6.7, iTunes 11.1.3, Sonic Studios Amarra 2.5, Songbird 1.9.3, or XLD; Western Digital NAS Device (2TB); Oppo BDP-103 universal Blu-ray player; Meridian Digital Media System (formerly Sooloos) (one Control 15, three TwinStores); Apple iPad Air, Mini; Apple iPod Touch 1G; Apple iPhone 4S; Benchmark DAC2 HGC, AudioQuest DragonFly 1.2 USB DACs.
Preamplifier: Marantz AV7005 in Pure Direct Mode.
Power Amplifier: Classé CAM 350 monoblocks (2).
…

I used Stereophile's loan sample of the top-of-the-line Audio Precision SYS2722 system (see www.ap.com and the January 2008 "As We See It") to examine the Channel Islands Audio Transient Mk.II's measured behavior. I used my 2012 Apple MacBook Pro running on battery power to examine the processor's performance via its USB port. For all tests, the Transient was powered from its VDC•5 Mk.II supply.

Apple's USB prober utility identified the Transient as the "CIAudio USB Audio 2.0" and confirmed that it operated in the optimal isochronous asynchronous mode with…

Editor: First, I'd like to thank the gang at Stereophile for reviewing our unique product.

As mentioned in Jon Iverson's review, we wanted this product to be completely portable, and to provide the industry-standard 2V analog output while running from USB power. There are only a small number of DAC integrated circuits with this capability that have the digital filtering and output stage built in. Being that there isn't much surrounding circuitry to work our "magic," we chose the IC that we felt offered the best musicality (not specs). In the end, I feel we…

Description: Upsampling, stereo D/A processor/headphone amplifier with independent volume controls for line-level and headphone outputs. Digital inputs: 1 S/PDIF (coax), 1 S/PDIF (TosLink), 1 USB 2.0 (type B). Analog outputs: 1 pair balanced (XLR), 1 pair unbalanced (RCA), 1 headphone output on ¼" (6.3mm) stereo phono jack. Compatible sample rates: 44.1–192kHz, all inputs. Frequency response: 10Hz–48kHz, –3dB, with 192kHz data. Channel separation: not specified. Signal/noise: 120dB ref. 0dBFS, A-weighted. THD+noise: >0.000316% (–110dB) at 0dBFS. Maximum…

Analog Source: Linn Sondek LP12 turntable with Lingo power supply, Linn Ekos tonearm, Linn Arkiv B phono cartridge.
Digital Sources: Marantz Reference NA-11S1 media player; Ayre Acoustics C-5xeMP universal player; Apple 2.7GHz i7 Mac mini laptop running OS10.7, iTunes 10, Pure Music 1.89, Audirvana Plus 1.5.10, JRiver Media Center 19 for Mac; NAD M51, Channel Islands Transient Mk.II, Auralic Vega D/A converters; Ayre Acoustics QA-9 USB A/D converter.
Preamplification: Channel D Seta L phono preamplifier, Pass Labs XP-30 line preamplifier.
Power…

I used Stereophile's loan sample of the top-of-the-line Audio Precision SYS2722 system (see www.ap.com and the January 2008 "As We See It") to examine the ASUS Xonar Essence One Muses Edition's measured behavior. I used my 2012-vintage Apple MacBook Pro running on battery power to examine the processor's performance via its USB port. Apple's USB Prober utility confirmed that the USB port operated in isochronous asynchronous mode and reported the processor's product string as "ASUS Xonar Essence One\000" from "ASUSTek Computer Inc." Peculiarly, the Mac's AudioMIDI…

Publisher's note: We anticipated a far stronger response to Bob Carver's duplication of the sound of our chosen reference amplifier (Vol.8 No.6), but the two comments below were the only official replies we received. On the other hand, many people in the industry spoke to us off the record, some in admiration, some in envy, some with a kind of disgust. I'm sure other amplifiers will come along that seem to defy duplication; perhaps Bob will be up to another challenge in a year or so.—Larry Archibald

From…