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Arcam Delta 170 CD Transport Into the Optic?

Sidebar 3: Into the Optic?

In a single week this past month, no fewer than six products with fiber-optic inputs or outputs have entered my listening room/test laboratory. This trend is a harbinger of the future as optical technology assumes an ever-increasing role in audio equipment. Since all three products reviewed here feature optical jacks, I thought this would be a good opportunity to provide a short primer on optical transmission of digital audio.

In a piece of copper wire transmitting digital audio, electrons carry the information in the form of pulses from one point to…

Audiostatic ES-100 loudspeaker

Thanks to Ben Peters, there's an electrostatic lifeline in Holland. Founded about 25 years ago, his company, Audiostatic, struggled through the 1980s, but with distribution by SOTA Industries, it's now on firm footing in the US. In fact, SOTA's Jack Shafton told me that all assembly and some manufacturing are now conducted in the US. My ES-100 samples came from the first US production run.

The speakers arrived on my doorstep via motor freight. Despite the crate they arrived in being made from wood, I discovered a narrow hole in its side—apparently the result of a forklift-blade attack.…

Audiostatic ES-100 loudspeaker Page 2

A multi-way dynamic speaker's radiation pattern is pretty messy—a number of lobes or sound streams trying to cohesively blend together. But for a full-range planar, the radiation pattern is characterized by two main lobes: one toward the front and another (180° out of phase) toward the back, with little radiation to the sides. This is the classic figure-8 pattern typical of dipole speakers, but with the Audiostatic the figure-8 is more of a three-dimensional entity running the panel's full length. If the panel is narrow and tall (which is the case here), it acts as a line source, minimizing…

Audiostatic ES-100 loudspeaker Page 3

While the ES-100s didn't have the MG-20s' tonal balance veracity through the lower octaves, the pair still managed to project some of that same kind of imaging magic into the soundstage. Instrumental outlines bloomed to realistic size, yet retained an exceptional sense of focus and individual identity. It was easy to resolve individual voices within the fabric of a chorus because outlines didn't blend or smear, as they often do with lesser speakers.

Timbre
In general, the Audiostatic's accuracy of timbre was right-on for instruments spanning the soprano register. In fact, the range…

Audiostatic ES-100 loudspeaker Measurements

Sidebar 1: Measurements

The Audiostatic's impedance magnitude (fig.1) only drops below 10 ohms in the mid-treble and above, reaching a minimum value of 5.7 ohms at 14kHz. It lies above 20 ohms in the midrange and bass—note the expanded scale on this graph—implying that the speaker is a very easy amplifier load, even considering the high capacitive phase angle below 100Hz. Its sensitivity, however, as DO suspected, is very low. Its B-weighted output on noise lies some 2.5dB below that of the already chronically low LS3/5a, implying a sensitivity of 80dB/W/m (footnote 1). Small amplifiers…

Audiostatic ES-100 loudspeaker Specifications

Sidebar 2: Specifications

Description: Full-range electrostatic loudspeaker. Frequency response: 35Hz–20kHz, ±5dB. Impedance: 6.5 ohms minimum. Sensitivity: 86dB/W/m. Recommended amplifier power: 50–250W.
Dimensions: 74" (1880mm) H by 13.8" (350mm) W by 1.4" (35mm) D. Weight: 51 lbs (23kg).
Serial numbers of samples tested: 9305100123 & 124.
Price: $3200/pair (standard finish), $3400/pair (wood finish) (1994); no longer available in the US (2011). Approximate number of dealers: 50.
Manufacturer: Audiostatic Holland, Klembergerweg 2, 7214 BL Epse, The Netherlands. Tel…

Keith Freund: <i>Constant Comments</i>

While listening to Keith Freund’s lovely Constant Comments, it’s often difficult to discern whether the sounds are coming from inside or outside the listening room. Voices, birdsong, honking horns, barking dogs, the opening and closing of doors, ocean waves and rainfall mingle, freely and happily, with crystalline and gently strummed electric guitars, synthesizer sounds, electronic burps and gurgles, tape hiss, and more.

The result is a comforting and thought-provoking ramble. Listening to Constant Comments is like walking down 3rd Street, between Coles and Monmouth, late at night,…

Reference Recordings Returns to LPs

In response to demand from its international customer base, Reference Recordings will release its first two LPs in 200-gram deluxe pressings on September 2. With disc mastering done at half-speed to insure cleaner reproduction and extended high frequency response, RR begins its new vinyl series with two highly prized analogue recordings from its extensive catalog. Dick Hyman From the Age of Swing arrives as a two-LP, 45rpm set, and Stravinsky: The Firebird Suite coupled with The Song of the Nightingale as a single 331/3rpm LP. The Stravinsky, performed by Eiji Oue and the Minnesota Orchestra…

Gradient Helsinki 1.5 loudspeaker John Atkinson, November 2010

John Atkinson reviewed the Gradient Helsinki 1.5 in November 2010 (Vol.33 No.11)

Art Dudley reviewed the Gradient Helsinki 1.5 in August 2010 (Vol.33 No.8). This unusual floorstanding loudspeaker combines a metal-dome tweeter and a 5" paper-cone midrange, each mounted in its own subenclosure, with a side-firing 12" paper-cone woofer. There is no enclosure for the woofer, giving it a dipole radiating pattern. "The Gradient Helsinki 1.5 is a remarkable product whose execution seems to lag only slightly behind its conception—and its conception is both original and, in its way, ingenious,"…

Third Annual Emofest

A look inside the impressive Emotiva ERC-2 CD player.

Audiophiles have been buzzing about Emotiva for a few years now. The attraction is no mystery: Emotiva’s products are solidly built and modestly priced, and the company takes pride in its strong relationships with customers. Yet, other than in the usual show report, Emotiva’s products have been absent from Stereophile’s pages.

But that will soon change: Our November issue will include Kal Rubinson’s thoughts on the Emotiva XPA-5 five-channel power amplifier, and, unless something crazy happens (always possible), I’ll discuss…