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There is always a conflict between the needs of reviewers and the realities of the marketplace. Once a reviewer has invested his time and energy in a review, he would like that product to remain in production for all time, which would allow it to be used as a reliable recommendation forever. But whatever the product and whatever the category, sales of a product almost always follow the same triangular curve: a sharp rise at the product's introduction, a maximum reached sometime thereafter, and then a steady decline to a sustained but low plateau. Marketing-minded manufacturers therefore…
The speaker output is taken from a pair of brass binding posts; a third binding post allows for independent grounding of the chassis, if necessary. Very usefully, in light of the M1.2's weight of 68.5 lbs, there is a pair of handles on the rear panel as well as on the front. When the amplifier is turned on, the output is muted and the red front-panel LED flashes while the tube warms up and the circuitry stabilizes. When the M1.2 Reference is ready to handle some music, a relay clicks and this LED glows steadily.
Sonics
I began my auditioning with the BBC LS3/5a's, which are…
Sidebar 1: Specifications
Description: Hybrid monoblock power amplifier with solid-state input stage, tubed driver stage, MOSFET output stage, comprehensive short-circuit protection, and high- and low-impedance bias settings. Tube complement: one 6922. Inputs: balanced on XLR with pin 2 wired hot; 2 single-ended on RCA connectors in parallel with pins 2 and 3 of XLR; 12V trigger. Outputs: 2 sets brass, gold-plated binding posts. Rated output power, high-impedance setting (minimum continuous sinewave power, 20Hz–20kHz): 110W into 8 ohms (20.4dBW) at <0.3% THD, 220W into 4 ohms (20.4dBW…
Sidebar 2: Associated Equipment
Digital Sources: Ayre Acoustics C-5xeMP & DX-5 universal players; Apple G4 Mac mini running OS10.5.8, iTunes 10, Pure Music 1.85; Shuttle PC with Lynx AES16 soundcard & dual-core AMD Athlon processor running Windows 7, Foobar 2000, Adobe Audition 3.0; dCS Debussy, Logitech Transporter, Mark Levinson No.30.6 D/A converters; Halide S/PDIF Bridge, Empirical Audio Off-Ramp4 USB-S/PDIF converters.
Preamplifier: Ayre Acoustics K-5xeMP.
Power Amplifiers: Classé CT-M600, MBL Reference 9007 (both monoblocks).
Loudspeakers: BBC LS3/5a, Sonus…
Sidebar 3: Measurements
To perform measurements on the Lamm M1.2 Reference, 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"). Before testing one of the monoblocks, I ran it at 1/3 its rated power into 8 ohms for 60 minutes, which thermally is the worst case for an amplifier with a class-A/B output stage. The output-stage bias switch was set to "1–6 ohms," which was how I had found the amplifier to sound best. At the end of that period the chassis was hot, with a temperature of 109.6°F (43.1°C), and…
Take a casual look at the Mk.II edition of MBL's Reference 101E Radialstrahler loudspeaker, and you won't immediately see what's new compared with the original version, which I reviewed in October 2004. But the Mk.II has a shorter, sleeker bass cabinet, designed to, among other things, slightly lower the stack of omnidirectional drivers it supports. While the many other major revisions to this familiar and fascinating loudspeaker can't be seen, it's fair to say that, from the ground up, the Reference 101E Mk.II is a new loudspeaker in design, if not in concept.
Since reviewing the…
All of which is to say that, tonally at least, and other than the bottom octaves, the 101E Mk.II is a blank slate on which, with your choices of associated gear (including cables), you can impose whatever sonic modifications you wish.
Cables
Anyone who's spent a lot of money assembling a system but who gets casual about cabling is missing the point. At the level of performance of the MBLs and my system, cables will spell the difference between supreme satisfaction and disappointment. MBL internally wires the 101E Mk.II with Wireworld cable. Jeremy Bryan had supplied me with a…
Sidebar 1: Specifications
Description: Four-way floorstanding loudspeaker. Three omnidirectional bending-mode drive-units: 24-segment carbon-fiber tweeter, 12-segment carbon-fiber upper-midrange unit, 12-segment aluminum lower-midrange unit; plus, in separate enclosure, bandpass-loaded 12", aluminum-cone woofer. Crossover frequencies: 105Hz, 600Hz, 3.5kHz (Linkwitz-Riley, fourth-order). Acoustic center: 45" (1140mm) from floor. Frequency range: 24Hz–40kHz. Sensitivity: 81dB/2.83V/m. Nominal impedance: 4 ohms. Power handling: 320–500W continuous, 2.2kW peak.
Dimensions: 67" (1720mm) H…
Sidebar 2: Associated Equipment
Analog Sources: Continuum Audio Labs Caliburn turntable & Cobra tonearm & Castellon stand; Graham Phantom II tonearm; Miyajima Labs Premium BE (mono), Ortofon A90, Soundsmith Sussurro cartridges.
Digital Sources: Simaudio Moon Evolution 650D DAC & CD transport, BPT-modified Alesis Masterlink hard-disk recorder, Meridian Sooloos music server, Pure Music software.
Preamplification: Ypsilon VPS-100 phono preamplifier; darTZeel NHB-18ns, MBL 6010D, Ypsilon PST-100 Mk.II preamplifiers.
Power Amplifiers: MBL Reference 9011 monoblocks,…
Sidebar 3: Measurements
I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the MBL Radialstrahler 101E Mk.II's frequency response in the farfield, and an Earthworks QTC-40 for the nearfield and spatially averaged room responses. Because of its bulk, I measured the speaker (serial no.233831) in Michael Fremer's driveway; though we raised it as far as practicable, the inevitable reflection of the speaker's sound from the ground affects the resolution of the measured response in the midrange. The axis chosen for the farfield measurements was level with the center…