Several days after those initial impressions, the Exposure did sound slightly better with its speaker leads reversed: Loudon Wainwright III's voice on the live "Mr. Guilty," from Unrequited (CD,…
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Usually, when I hear something like that, I try reversing the amp's absolute polarity by swapping the loudspeaker connections at both channels. More often that not, the source of the problem is that the design just happens to reverse polarity—no big deal. But when I did that with the Exposure 3010S, I couldn't hear much of a difference: Leading-edge transients were a bit blunted, no matter what.
Sidebar 1: Specifications
Description: Solid-state integrated amplifier with remote control. Line inputs: 6 (one adaptable for phono use with optional phono stage) plus tape output. Line input impedance: 17k ohms. Optional phono input impedance: 47k ohms (moving-magnet board; moving-coil board is adjustable from 100 ohms to 1500 ohms). Frequency response: 20Hz–20kHz, ±0.5dB. Total harmonic distortion: <0.03 % at rated output, 1kHz. Channel separation: >60dB, 20Hz–20kHz. Output power: 110Wpc into 8 ohms, 1kHz.
Dimensions: 17.2" (440mm) W by 4.5" (115mm) H by 11.7" (300mm) D.…
Sidebar 2: Associated Equipment
Analog Sources: Linn LP12 (with Linn Basik power supply), Thorens TD 124 Mk.II turntables; Naim Aro, EMT 997 tonearms; Miyabi 47, EMT OFD 25, Ortofon SPU Synergy A cartridges.
Digital Source: Sony SCD-777ES SACD/CD player.
Preamplification: Auditorium 23 Standard, K&K Audio, EAR MC4 step-up transformers; Shindo Masseto preamplifier.
Power Amplifiers: Shindo Cortese, Quad II.
Loudspeakers: Audio Note AN-E/SPe HE, Quad ESL.
Cables: Interconnect: Audio Note AN-Vx, Shindo silver. Speaker: Auditorium 23, DNM. AC: JPS Labs The Digital AC (SACD…
Sidebar 3: Measurements
I measured the Exposure 3010S using Audio Precision's top-model SYS2722 system (see www.ap.com) for most of the tests, with some use made of the older AP System One. As usual, I preconditioned the amplifier by running both channels at one-third power into 8 ohms, which maximally stresses an amplifier with a class-B or -AB output stage. The normal preconditioning period is one hour, but the Exposure turned itself off after just 20 minutes. While the chassis was warm, the area of the top cover above the internal heatsink was almost too hot to keep my hand on.…
After using Bel Canto's e.One DAC3 with the McIntosh Laboratory MS750 music server, I was so impressed that I wanted to hear Bel Canto's CD transports as well. But willing as Bel Canto president and CEO John Stronczer was to supply me with a CD-2, he suggested I audition the S300iu ($2195, footnote 1).
"The S300i is a 150Wpc integrated amplifier, and the 'u' suffix means it's been outfitted with a USB-input-only DAC (a $200 option)," Stronczer explained. "We're pretty excited about it, and we think it's a logical first step for someone who has never seen the point of high-end…
The S300iu is completely straight-ahead in terms of setup. It doesn't produce much in the way of heat, so placement isn't a problem—and the remote means you can even put it where it's hard to reach. Bel Canto suggests that its "performance starts to stabilize after about 100 hours of continuous power up." Perhaps it did, but the difference wasn't as drastic as some I've heard—primarily in components with Teflon capacitors.
The nest
I installed the S300iu in my smaller dedicated listening room, driving the Usher Be-718 speakers (reviewed in the May issue), using my Apple G4 iBook as…
Sidebar 1: Specifications
Description: Integrated amplifier with optional USB DAC or phono stage. Preamplifier section: Frequency range: DC–200kHz. Signal/noise (A-weighted, ref. 2V RMS): >95dB, Input overload: 10V. Input impedance: 10k ohms. Output impedance: 500 ohms. Maximum gain: 20dB. Maximum output level: 9.5V. Amplifier section: Maximum output power: 150Wpc into 8 ohms (21.75dBW), 300Wpc into 4 ohms (21.75dBW). Minimum rated load impedance: 4 ohms. Frequency response: 20Hz–20kHz, ±0.5dB. Voltage gain: 27dB. Damping factor: >1000. Output impedance: <8 milliohms. THD+noise…
Sidebar 2: Associated Equipment
Digital Source: Apple G4 iBook computer, McIntosh Laboratory MS750 music server, Bel Canto e.One DAC3 D/A converter.
Integrated Amplifier: Ayre AX-7e.
Loudspeakers: KEF Reference 201/2, Usher Be-718.
Cables: Interconnect: Shunyata Research Aries & Antares. Speaker: Shunyata Research Lyra.
Accessories: Ayre L-5xe line filter; Furutech eTP-609 distribution box; APC S15 AC line conditioner; Furutech RDP panels, RealTraps Mini & Mondo Traps.—Wes Phillips
Sidebar 3: Measurements
As I usually do with amplifiers, I preconditioned the Bel Canto e.One S300iu by running both channels at one-third the maximum power into 8 ohms for one hour. Thermally, this maximally stresses an amplifier with a class-B or -AB output stage. But with its class-D output stage, the Bel Canto hardly got warm.
I measured the S300iu using Audio Precision's top-model SYS2722 system (see www.ap.com) for most of the tests, with the obsolete AP System One bringing up the rear. The S300iu's maximum gain into 8 ohms was 46.5dB, which is a little higher than usual for…
Reality check number one. Tired of reading about the latest and greatest $65,000 loudspeakers? Or even the current hot ticket at $2500? Such loudspeakers promise to bring you the audio truth, or the golly-gee-whiz, honest-to-gosh, absolutely positively real sound. And some of them do seem to come awfully close, though truth be told, we're still a long way from replicating reality—and will never do it with just two channels.
The truth may be "out there," but we're in here. And the truth has always included the fact that, beyond a certain point, doubling the price buys an increasingly…