I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the Joseph Audio Pulsar's frequency response in the farfield, and an Earthworks QTC-40 for the nearfield and spatially averaged room responses. As Michael Fremer conjectured, the Pulsar is relatively insensitive, my estimate of its voltage sensitivity coming in at 83.5dB(B)/2.83V/m. However, as indicated by its plot of impedance magnitude and electrical phase against frequency (fig.1), the Pulsar is an easy load for the partnering amplifier to drive. Not only is the phase angle relatively…
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Even at its humblest, a 300B is a fine thing. And at its best, this classic triode output tube can deliver some of the most intoxicating music playback imaginable. If tubes are liquor, the 300B is clearly absinthe. (The 2A3 is Cognac, the 45 is Armagnac, the F2a is Tequila, and the EL34 is vodka—which is to say, you can make almost anything out of an EL34, from the repulsive to the sublime.)
In the 20 years since the 300B reappeared on the home audio stage, the tube has appeared in a few thoroughly original designs; of those few, the ones I've heard have sounded magnificent. The 300B has…
Subjectively, the Allnics provided virtually the same generous amount of gain as my Shindo amplifiers (an early Haut-Brion stereo amp and a pair of Corton-Charlemagne monoblocks). The Shindos are equipped with level controls, which prevent me from having to use all of that gain all of the time. At first I took the two Allnic monoblocks to slightly differ in gain from each other, yet as the days and weeks wore on, I realized that that wasn't the case: Rather, the Allnics' high gain had led me to keep the volume potentiometer of my Shindo Masseto preamp turned to the low end of its range,…
Sidebar 1: Specifications
Description: Single-ended tubed monophonic power amplifier. Tube complement: one each CV1673, 3A/110B, 300B, 5U4G. Output power: 10Wpc into 8 ohms at 1kHz (10dBW). Input sensitivity: ca 0.6V for rated power. Input impedance: 100k ohms. Output impedance: 8 or 16 ohms (selectable). Damping factor: 4.7 at 1kHz into 8 ohms. Voltage gain: 24dB. Distortion: 0.5% at 1kHz into 8 ohms, 2.83V output. Frequency range: 20–20kHz, flat.
Dimensions: 17" (435mm) W by 9.5" (245mm) H by 12.5" (320mm) D. Weight: 44 lbs (20kg).
Serial numbers of units reviewed: 24035, 24036…
Sidebar 2: Associated Equipment
Analog Sources: Garrard 301, Thorens TD 124 turntables; EMT 997, Schick tonearms; Ortofon SPU, EMT TSD 15 70th Anniversary & OFD 25 pickup heads, Miyajima Premium Mono BE cartridge (in Yamamoto headshell).
Digital Sources: Wavelength Proton USB D/A converter; Apple iMac G5 computer running Apple iTunes v.10.2.2, Decibel v.1.0.2 playback software; Sony SCD-777ES SACD/CD player.
Preamplification: Auditorium 23 Standard (SPU version), Robyatt Mono, Silvercore One-to-Ten step-up transformers; Shindo Masseto preamplifier.
Power Amplifiers:…
Sidebar 3: Measurements
The measurements of the Allnic A-5000 DHT (serial no.24036) were performed with Stereophile's loan sample of the top-of-the-line Audio Precision SYS2722 system (see the January 2008 "As We See It," and www.ap.com). The needle of the front-panel bias switch rested on the C of the Allnic logo, which is within the limits for output-tube bias current. I didn't need to adjust it, therefore.
The voltage gain into 8 ohms for single-ended sources was both on the low side for a power amplifier, and slightly lower than specified, at 23.7dB from the 16 ohm output-…
In March 2006 I wrote a very favorable review of Monitor Audio's Silver RS6 loudspeaker. At the time, I felt this $999/pair, small-footprint floorstander produced the greatest sound quality per dollar of any speaker I'd heard. Despite the proliferation of affordable speakers of increasing quality I've heard since then, I remained particularly impressed by the Silver RS6's clarity and lack of coloration and the speed of its midbass, all of which continued to exceed the performance of any other affordable speaker I've heard.
At one point, after the review was published, I invited my…
The RX6's high-frequency purity nicely dovetailed with its perfect rendition of crisp, clean, fast transients on recordings with percussive content. The bell-like knocks and shimmies of Philipp Vandré's instrument on Cage's The Piano Works 2 (CD, Mode 50) were extended and detailed, with just the right amount of decay. Similarly, Egberto Gismonti's guitar playing is quite percussive in his duets with percussionist Nana Vasconcelos on their Duas Vozes (CD, ECM 1279); the Monitors created a lifelike sense of churning rhythm. With busy and angular jazz fusion, the speaker had a sense of…
Sidebar 1: Specifications
Description: Two-and-a-half-way, ported floorstanding loudspeaker. Drive-units: 1" (25mm) C-CAM gold dome tweeter, 6" RST mid/woofer, 6" RST woofer. Crossover frequencies: 700Hz LF, 2.7kHz MF/HF. Frequency range: 38Hz–35kHz. Sensitivity: 90dB/W/m. Nominal impedance: 6 ohms. Maximum SPL: 114.8dBA. Power handling: 125W RMS. Recommended amplification: 40–125W RMS.
Dimensions: 35 5/8" (905mm) H by 1013/16" (275mm) W by 123/16" (310mm) D (includes plinth and feet). Weight: 36.13 lbs (16.4kg).
Finishes: Black Oak, Natural Oak, Walnut, Rosenut (all real wood);…
Sidebar 2: Associated Equipment
Analog Sources: VPI TNT IV, Rega Planar 3 turntables; Immedia, Syrinx PU-3 tonearms; Koetsu Urushi, Clearaudio Virtuoso Wood cartridges.
Digital Sources: Lector CDP-7T, Creek Destiny CD players.
Preamplification: Vendetta Research SCP-2D, Creek Destiny phono stages; Audio Valve Eclipse line stage.
Integrated Amplifier: Creek Destiny.
Power Amplifier: Audio Research Reference 110.
Loudspeakers: Epos M5i, Dynaudio Excite X12, Monitor Audio Silver RS6.
Cables: Interconnect (all MIT): Magnum M3, MI-350 CVTwin Terminator, MI-330SG…