Robert Harley

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Robert Harley Posted: Aug 26, 2011 Published: Oct 01, 1989 0 comments
The Arcam Delta 170 is one of the first examples of an entirely new product category: CD transports. The concept of different CD transports having different sonic qualities is vexing. It is a simple matter to prove that the bit stream contains identical data from virtually any CD transport (see "Industry Update," Vol.12 No.8). According to Arcam, development of the Delta 170 was spurred by audible differences among transports heard by dealers, customers, and Arcam staff. The possibility that CD transports have their own sonic signatures is intriguing.
Robert Harley Posted: Aug 08, 2011 Published: Jun 01, 1991 2 comments
The past 12 months have seen some remarkable developments in digital playback. Standards of digital musicality are far higher than they were a year ago, both on an absolute performance basis and in terms of what you get at various price levels. No other component category has seen such tremendous gains in value for money or number of new products introduced. It seems hard to believe that since Vol.13 No.6 (12 issues ago), we've reviewed such noteworthy digital processors as the Meridian 203, Proceed PDP 2, Stax DAC-X1t, Theta DSPro Basic, Wadia X-32, Esoteric D-2, PS Audio SuperLink, and VTL D/A. Each of these converters brought a new level of performance to its price point—or, in the case of the Stax and VTL, established a new benchmark of ultimate digital performance.

Just as these units provided stiff competition for previous products, so too will they come under the assault of improving technology. The art of digital processor design is so young that we can continue to expect further improvements coupled with lower prices as designers move up the learning curve.

Robert Harley Posted: Jul 05, 2011 Published: Oct 15, 1989 0 comments
The rapidly evolving world of the late 20th century is the source of much stress. Changes in the status quo, whether wrought by social, political, or technological forces, are often accompanied by anxiety brought on by the struggle to assimilate new patterns of thought. New ideas necessitate abandoning or modifying one's old ideas, thus creating conflict (footnote 1). However, these periods of rapid change can also be exciting, allowing one to chart a course of discovery and growth.
Robert Harley Posted: May 31, 2011 Published: Jan 01, 1990 0 comments
The VTL 225W DeLuxe monoblocks are very similar to the 300W monoblocks that received such an enthusiastic reception from J. Gordon Holt a year or so ago (in Vol.11 No.10) and, ultimately, most of the audiophile community. Technically, they differ only in output tubes and transformer: the 225W uses EL34s, the 300W uses 6550s. The 225Ws, at $4200/pair, cost $700 less than their more powerful brothers. The question may be raised: Why have two models so close in price and performance? According to David Manley, the 225Ws were built on special order for audiophiles who preferred the sound of EL34s to the 300Ws' 6550s. Demand was so great for the EL34 version that he decided to add it to the line. They look almost identical, the only difference being the smaller output transformer on the 225W and an additional filter capacitor on the 300W's top chassis.
Robert Harley Posted: May 03, 2011 Published: Jan 01, 1990 0 comments
The name Muse Electronics is probably unfamiliar to most audiophiles, requiring some background on the company. Muse is the hi-fi offshoot of a company called Sound Code Systems, a manufacturer of professional sound-reinforcement speaker cabinets and power amplifiers. Founded in 1980, SCS enjoyed some success with its line of MOSFET professional power amplifiers. In 1988, SCS's Michael Goddard and Kevin Halverson, both audiophiles and tube aficionados, redesigned their amplifier for the high-end hi-fi market.

The results are the Model One Hundred (a 100Wpc stereo power amplifier) and the Model One Hundred Fifty ($1900/pair), the 125W monoblock reviewed here. According to Michael Goddard, the primary design goal was to achieve a tube sound with the reliability and ruggedness of transistors. MartinLogan CLS speakers were used extensively during the design/listen/design cycle. As a result of their listening auditions and redesign, many of the changes have now been incorporated into their professional products.

John Atkinson Robert Harley Posted: Mar 31, 2011 Published: Feb 01, 1989 0 comments
As explained by Ken Kessler elsewhere in this issue, the English A&R Cambridge company made their name by producing one of the UK's most successful integrated amplifiers, the 40Wpc A60. This neatly styled model was in production for a decade or so and was the basis for a large number of good-sounding but inexpensive audio systems. These days, the company, whose products in the US sell under the Arcam banner, is a major British hi-fi manufacturer, with a product line that includes integrated amplifiers, tuners, loudspeakers, cartridges, and even a CD player. A&R was, I believe, the first UK manufacturer to obtain a player-manufacturing license from Philips, and with the product under review here, has broken new territory for a supposedly "audiophile" company in having a custom LSI chip manufactured to their own requirements.
Robert Harley Posted: Feb 08, 2011 Published: Apr 01, 1991 0 comments
The Snell Type C/IV's design has been highly influenced by both the testing methods and philosophy of Canada's National Research Council in Ottawa. Other well-known loudspeakers to have benefited from the NRC's testing facilities include the Mirage M-1 and M-3, PSB Stratus Gold, the Waveform, and Camber 3.5. The NRC provides a variety of services to loudspeaker designers, notably use of their testing facilities which include a full-sized anechoic chamber. In addition, the NRC is heavily involved in carefully controlled blind listening comparisons between loudspeakers, used to aid the loudspeaker designer while the product is under development. The NRC doesn't provide design services, but rather the means of testing and evaluating work in progress and finished products.

Despite not offering design aid, many loudspeakers created with the NRC's testing and listening laboratories share some common philosophies. Chief among these is the belief that flat amplitude response is far and away the most significant factor in listener preferences and thus should be the paramount design goal. Many NRC-influenced loudspeakers share steep crossover slopes, wide dispersion, smooth off-axis response, and pay considerable attention to the way the loudspeaker interacts with the listening room.

Robert Harley Posted: Feb 08, 2011 Published: Apr 01, 1991 3 comments
Last July I reviewed the $4850/pair Hales System Two Signature loudspeakers and enthusiastically recommended them. In fact, they displaced the B&W 801 Matrix 2 as my reference loudspeaker, and have become a fixture in my listening room. Over the past seven months, my impressions of the Signatures have been largely confirmed: transparent and uncolored midrange, resolution of fine detail, precise imaging, superb transient abilities, and, most importantly, an ability to thoroughly involve the listener in the music. These qualities earned the Signature a Class A recommendation in Stereophile's "Recommended Components." I've greatly enjoyed the many hours spent with the Signatures.

Hales Audio makes another loudspeaker—the System Two reviewed here—that is very similar to the Signature, but much less expensive (footnote 1). Because the System Two is such a close relation to the Signature—it uses identical drivers, a nearly identical crossover, and similar cabinet construction—and costs nearly 2 kilobucks less, I was eager to hear what the smaller system had to offer. Because the Signature was recommendable at $4850, the System Two just might be a bargain at $3000 if it even came close to the Signature's musicality.

Robert Harley Posted: Jan 02, 2011 Published: Oct 02, 1990 2 comments
Cyrus is the name given to the higher-priced line of loudspeakers made by England's Mission Electronics. The entire Mission loudspeaker line includes six products under the Mission label and three under Cyrus. Mission also manufactures a wide range of electronics and CD players. The company has a long history of audio innovations, both in loudspeaker and electronic design. Among Mission's claimed "firsts" are the first polypropylene-cone drive-unit used in a product (1978), first widespread use of MDF loudspeaker enclosures (1981), and first CD player from a specialist manufacturer. Interestingly, Mission also makes IBM-compatible personal computers.

The $900/pair Cyrus 782 is a two-way design employing dual 7" (175mm) polypropylene-cone woofers and a single ¾" (19mm) fabric-dome tweeter. The drivers are arranged in a D'Appolito configuration to simulate point-source radiation characteristics. Both woofer and tweeter were designed from scratch by Mission. The polypropylene woofer cones include a "mineral loading" that reportedly increases cone rigidity, thus decreasing cone breakup. Additional woofer design features include a shaped pole piece to increase linearity during high cone excursions, rigid steel chassis to reduce driver resonances, and a tight tolerance between the voice-coil and magnet to increase sensitivity.

Robert Harley Posted: Dec 04, 2010 Published: Mar 15, 1994 0 comments

It seems to me that it should be possible to make a perfectly jitter-free CD transport without resorting to elaborate, expensive mechanical structures. This idealized transport would ignore all mechanical considerations of disc playback—vibration damping and isolation, for example—and simply put a jitter-free electrical driver at the transport output. If such a circuit could be made, it wouldn't care about how bad the signal recovered from the disc was (provided the recovered data were error-free). The circuit would just output a perfect, jitter-free S/PDIF signal. The result would be the sound quality of the $8500 Mark Levinson No.31 Reference CD transport in $200 machines. Such a scheme would provide an electrical solution to what has been considered largely a mechanical problem.

But back in the real world there's no doubt that attention to mechanical aspects of transport design affects sound quality. Examples abound: listening to Nakamichi's 1000 CD transport with its Acoustic Isolation door open and closed; playing the Mark Levinson No.31 with the top open; and putting any transport on isolation platforms or feet are only a few of the dozens of experiences I have had that suggest that mechanical design is of utmost importance.

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