Who said this? John Atkinson? Art Dudley? Dr. Dre? These are the thoughts of Roy Gandy, innovator, venerable designer, and founder of Rega Research, quoted from his company's recent biography, A Vibration Measuring Machine, a hefty, 311-page, large-format hardcover co-written by Gandy, Bill Philpot, and Stereophile's Paul Messenger.
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"lt's kind of Roy's philosophy," Bateman explained. "The Brio is the amplifier equivalent of a Planar 3 turntable, which is no-frills. Digital would get in the way. It's like the old amplifiers of 40 years ago: the Creek CAS4040, Arcam A60, or the Sugden…
Description: Solid-state, class-AB integrated amplifier. Analog inputs (RCA): 4 unbalanced line, 1 unbalanced MM phono. Outputs: 1 pair speaker terminals, 1 pair unbalanced (RCA) "Record," 1 headphone ¼" jack. Output power (both channels driven): 50Wpc into 8 ohms (17dBW), 73Wpc into 4 ohms (15.9dBW). Headphone output: 32 ohms = 1.8V, 54 ohms = 2.6V, 300 ohms = 5.9V. Source impedance: 109 ohms. Frequency response: 12Hz–43kHz (line); 15Hz–40kHz, –3dB (phono); 27Hz–20.5kHz, –1dB (phono). Distortion: typically 0.03%, 1dB below clip, 22Hz–22kHz. Signal/noise ratio (…
Analog Sources: Kuzma Stabi S turntable & Stogi S tonearm; Music Hall MMF-7.3 turntable; Denon DL-103, Goldring Elite MC, Ortofon 2M Bronze cartridges.
Digital Sources: Apple MacBook computer running Audirvana Plus; Ayre Acoustics QB-9DSD DAC; LG BD-550 BD player; Western Digital T2 Mirror Drives (2).
Preamplification: Auditorium 23 A23 moving-coil step-up transformer, Heed Audio Quasar phono stage, Shindo Laboratory Allegro preamplifier.
Power Amplifier: Shindo Laboratory Haut-Brion.
Integrated Amplifier: Heed Audio Elixir.
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I performed a full set of measurements on the Rega Brio, using my Audio Precision SYS2722 system (see the January 2008 "As We See It"). Via its line inputs, the Brio's maximum voltage gain into 8 ohms was typical for an integrated amplifier, at 39.55dB. The amplifier inverted absolute polarity for line input signals at both the speaker terminals and headphone jack, and its input impedance at 20Hz and 1kHz was, at 41k ohms, fairly close to the specified 47k ohms. Though the line input impedance dropped to 36k ohms at 20kHz, this will be inconsequential.
The…
Sound Quality
After experimenting with positioning the Reference 5s in my room, Jack Oclee-Brown eventually decided on using the long port for the two top woofers and the short port for the two bottom…
Description: Three-way, reflex-loaded, floorstanding loudspeaker. Drive-units: Uni-Q driver array with 1" (25mm) vented aluminum-dome tweeter, 5" (125mm) aluminum-cone midrange unit, four 6.5" (165mm) aluminum-cone woofers. Crossover frequencies: 350Hz, 2.8kHz. Frequency response: 40Hz–35kHz, ±3dB. Frequency range: typical in-room bass response, 25Hz, –6dB; free field, short port, 35Hz–45kHz, –6dB; free field, long port, 32Hz–45kHz, –6dB. Sensitivity: 90dB/2.83V/m. Nominal impedance: 8 ohms. Minimum impedance: 3.2 ohms. Harmonic distortion (2nd & 3rd…
Analog Source: Linn Sondek LP12 turntable with Lingo power supply, Linn Ekos tonearm, Linn Arkiv B cartridge.
Digital Sources: Aurender N10 music server; Ayre Acoustics C-5xeMP universal player; Ayre Acoustics QX-5 Twenty & QB-9DSD, PS Audio PerfectWave DirectStream D/A converters; AudioQuest JitterBug, UpTone Audio ReGen USB cleaner-uppers; Mac mini running Vinyl Studio, Pure Music 3, Audirvana 1.5, Roon 1.3; Ayre Acoustics QA-9 USB A/D converter.
Phono Preamplifier: Channel D Seta L.
Preamplifier: Ayre Acoustics KX-5 Twenty.
Power…
I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the KEF Reference 5's frequency response in the farfield, and an Earthworks QTC-40 for the nearfield and in-room responses. The Reference 5's specified sensitivity is 90dB/2.83V/m; my estimate was slightly lower, at 89.1dB(B)/2.83V/m. Its impedance is specified as 8 ohms with a minimum magnitude of 3.2 ohms. Fig.1 shows how the impedance and electrical phase vary with frequency. While the impedance lies above 8 ohms in the low treble, it remains between 4 and 5 ohms throughout the…