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Listening #88 / Tempo Electric Arthur Loesch 1.1 Control Preamplifier

I am not in the mood for whirling.—the Beatles, "Revolution 9"

The single-ended-triode movement of the 1990s may not have changed everyone's point of view, but its aftershocks endure. Low-power amps sell well. The market for high-efficiency loudspeakers is healthier than ever. Even vinyl's most recent renaissance can be linked, in part, to a rekindled interest in old tubes and technologies. Best of all: Some of the thinkers and designers who came for the Revolution decided to stay for the Great Leap Forward.

Though hardly a household name, Arthur Loesch is revered in SET…

Listening #88 / Tempo Electric Arthur Loesch 1.1 Control Preamplifier Page 2

The second phono gain stage uses an RCA 6GK5 tube. The 1.1's third and final phono gain stage incorporates half of a Tung-Sol 5687 dual triode—the second half of which is used to provide 18dB of line-stage gain. That tube, like the abovementioned 6GK5, is used in a fixed-bias arrangement originated by Dr. Loesch, wherein the DC for the tube's signal grid is supplied by a replaceable battery. (In a product such as this, with a comparatively low voltage rail—260VDC is the intended B+—the traditional advantages of an auto-bias circuit would be moot.) In exchange for the slight inconvenience of…

Listening #88 / Tempo Electric Arthur Loesch 1.1 Control Preamplifier Page 3

All of those changes coaxed the system further from egregious brightness toward simply sounding extended, wide-open . . . and detailed. With the Arthur Loesch 1.1, not only could I pinpoint the exact moment when organist Benmont Tench switched his Leslie rotating speaker from fast to slow toward the end of every chorus of "Echo," from the Tom Petty album of that title (CD, Warner Bros, 47294-2), I could clearly hear it decelerate. And the 1.1 was perfect for cataloging the differences between the well-known stereo mix of The Beatles (CD, 1987 remastering, Parlophone CDP 7 46443/4 2) and that…

Marantz PM-KI-Pearl integrated amplifier

To celebrate his 30 years with the company, Marantz threw designer Ken Ishiwata a birthday party in the form of an assignment: Design a new, limited-edition integrated amplifier and SACD/CD player bearing his initials. (Only 500 of each will be made worldwide.)

In a review of some Marantz separates a few years ago, I wrote that in Ishiwata, who works out of his offices in Eindhoven, The Netherlands (Marantz was once owned by Philips), the company has a unique "secret weapon." Ishiwata is a decidedly noncorporate soul who nonetheless thrives within that environment, and who…

Marantz PM-KI-Pearl integrated amplifier Page 2

The Pearl borrows much of its amplifier technology from Marantz's far more expensive line of separates and more powerful integrated products. Marantz's HDAM-SA3 ultra-high-speed amplifier modules are used throughout, including in the phono stage, which Ishiwata tuned with particular care. And because he's a vinyl fan, he used higher-grade capacitors in the phono stage.

Facilities
The PM-KI-Pearl is a full-featured, remote-controlled integrated amplifier that includes a special wide-bandwidth CD input, a phono input that can be switched between moving-magnet and moving-coil, two line…

Marantz PM-KI-Pearl integrated amplifier Page 3

If you buy a PM-KI-Pearl, be sure to plug your best digital source into the wider-band CD input—when I did, it made a surprisingly big difference. When I used the Sooloos to hear again the few dozen songs I'd just played, the sound took a major step toward a leaner, better-controlled, more focused bottom end; the midrange transparency was noticeably better, the low-level detail was sharper, transients were better defined. Rhythm and pacing improved. It was like going from the tubed to the solid-state output of a CD player equipped with both. Which you'll prefer will depend on your taste and…

Marantz PM-KI-Pearl integrated amplifier Specifications

Sidebar 1: Specifications

Description: Solid-state, remote-controlled, stereo integrated amplifier with 5 line inputs (2 associated with tape loops), 1 MM/MC phono input. Power output: 90Wpc into 8 ohms (19.5dBW), 140Wpc into 4 ohms (18.5dBW). Frequency response (CD, 1W, 8 ohm load): 5Hz–100kHz, ±3dB. Output bandwidth (8 ohm load, 0.05% THD+N): 5Hz–40kHz. Input sensitivity: CD/line, 240mV/20k ohms; phono (MC), 270µV/100 ohms; phono (MM), 2.7mV/47k ohms; P. Direct in: 1.7V/20k ohms. Pre-out output voltage/output impedance: 1.7V/220 ohms. Phono overload: MC, 15mV; MM, 150mV. THD: 0.05%,…

Marantz PM-KI-Pearl integrated amplifier Associated Equipment

Sidebar 2: Associated Equipment

Analog Sources: Continuum Audio Labs Caliburn, Cobra, & Castellon turntable, tonearm, and turntable stand, Ariston Q Deck turntable; Graham Engineering Phantom II tonearm; Lyra Titan i, Transfiguration Orpheus, Ortofon A90, Shure M97xE cartridges.
Digital Sources: BPT-modified Alesis Masterlink hard-disk recorder, Meridian-Sooloos music server; Camelot Technology Round Table used as D/A converter.
Preamplification: Manley Steelhead, Einstein Turntable's Choice, Boulder 1008 phono preamplifiers.
Power Amplifier: Musical Fidelity Titan.
…

Marantz PM-KI-Pearl integrated amplifier Measurements

Sidebar 3: Measurements

I measured the Marantz PM-KI-Pearl with Stereophile's loan sample of the Audio Precision SYS2722 system (see the January 2008 "As We See It" and www.ap.com); for some tests, I also used my vintage Audio Precision System One Dual Domain.

Before I test an amplifier, I run it for 60 minutes at one-third its specified power into 8 ohms. Thermally, this is the worst case for an amplifier with a class-B or -AB output stage. At the end of this period, the Marantz's case was warm to the touch, but the grilles above its internal heatsink weren't so hot that I…

Balanced Audio Technology VK-55SE power amplifier

I hate audio shows. All those manufacturers and retailers desperately demonstrating their products, knowing how impossible it is to do them justice in a hotel room. They might be saying, "It has gold-plated circuit boards and unobtainium binding posts," but all I hear is Please love it, please love it, oh puhleeze . . .

I love audio shows. Of all those people gathered together to commit hi-fi, a handful of them actually get it right and make it look effortless—Balanced Audio Technology's Geoff Poor, for example. You can count on the latest BAT products to sound better than the…