Friday, May 2, 2008

Silverline Audio Technology Prelude loudspeaker

Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
Silverline Audio Technology Prelude loudspeaker 
HI-FI, Sterio, Home Theater, Audiophile, Amplifier, Speaker

It must be difficult for makers of audio equipment to decide how to best exhibit their products at events such as the annual Consumer Electronics Show. If you're doing a demo, you want it to impress audio journalists and potential dealers, and sometimes just playing music is not enough: you need something extra. A few years ago, Joseph Audio put on a demo, supposedly of their top-of-the-line floorstanding speaker, during which Jeff Joseph removed a cloth that had been draped over what was assumed to be hotel-room furniture. Under that cloth were the speakers that were actually playing: Joseph's new in-wall model, mounted on flat baffles. Wilson Audio Specialties demonstrated their speakers with purportedly ultra-high-end electronics and digital source, then revealed that they were actually using a modestly priced preamp and power amp, and that the source was an Apple iPod.

Such demos can be effective in convincing listeners that the speakers are better than their price would suggest, or that expensive speakers don't necessarily require correspondingly expensive electronics to make them sound good. However, they can also backfire: people, especially reviewers, don't like to be fooled, and their wrath is likely to be directed at the manufacturer. (I, of course, could instantly tell that there was something amiss.)

At the 2006 CES, Silverline Audio Technology demonstrated their diminutive, floorstanding Prelude loudspeaker in a manner designed to prove that their performance is well above what their size and price would indicate, but this demo involved no deception. The Preludes were set up in a system that used 600Wpc Pass amplifiers, and the demo featured a recording of a percussion ensemble played at a blow-the-man-down level. I expected to see the mid/woofer cones fly across the room. Instead, I heard clean, dynamic music. Impressed, I requested a pair for review.

Which Prelude?
My auditioning of the Silverline Prelude proceeded in a routine way, with no problems such as drivers being wired out of phase or binding posts breaking when tightened. I set up the speakers in positions that I thought would work for them, listened, tweaked the setup, listened again, experimented with various associated components, listened some more, then wrote up the review and submitted it to John Atkinson. I was done with the Preludes.

Or so I thought. A few weeks later, before the review manuscript had gone through the normal editing process, I received an e-mail from Silverline's Alan Yun, designer of the Prelude. He informed me that some changes had been made in the speaker. The cabinet walls were now thicker; the two small rear ports had been replaced with a single larger one; the crossover was now mounted directly on the binding-post board, resulting in a shorter signal path; the plinth was made bigger to improve stability; and there were new, heavier-duty floor spikes. Such changes can have a substantial effect on a speaker's sound—it was clear that I'd have to listen to the revised model.

As it turned out, the Prelude had undergone other changes potentially even more important. These included a new tweeter (bigger magnet motor and coil, more refined protection grille), a new woofer (with double magnets, for greater sensitivity and power handling), and a redesign of the crossover to accommodate the driver and port changes. Now, you might think that so many changes would easily justify naming the revised model the "Mk.II" or "Series 2" or "Special Edition." Not so. (Apparently, very few pairs of the original Prelude were sold.) In this and the "Listening, Take 2" sections I refer to the first and second sets of review samples as "Original" and "Revised," respectively. "Listening, Take 1" is, nearly verbatim, the review's original "Listening" section.

One thing the Original and Revised Preludes have in common is that they're small. If you place a paperback book atop one, borders of the speaker's top surface of only about ½" wide (Original) or ¾" wide (Revised) would still be visible. Although the Revised has thicker walls, the Original's interior dimensions have been retained (though for some reason the Revised is about ¾" shorter). The Original had brass binding posts, the Revised the familiar plastic ones; I first thought this was to comply with European safety rules, but an e-mail from Alan Yun informed me that the plastic posts were used only for the review samples; the production Reviseds will have brass posts. The wooden plinth (8¼" by 9" on the Original, 8¾" by 11½" on the Revised) attaches to the body of the speaker with heavy-duty bolts. Screw-in spikes are provided (the Revised's are thicker), but the user is warned not to install these until he or she is sure that the speaker positions are optimal. The Revised's cabinet has a "wraparound" construction, and while neither version will challenge the appearance of a Sonus Faber loudspeaker, the Revised gives a more upscale impression.

According to Alan Yun, design of the Prelude began in 2003, the aim being to produce a full-range, mini-floorstanding speaker that would satisfy "the most demanding audiophiles and music lovers where budget and space are of the most concern." The key to this was the design of a midrange/woofer with a lightweight but extremely rigid cone of aluminum-magnesium alloy. Two of these drive-units are used, with a 1" tweeter mounted in a woofer-tweeter-woofer arrangement. This type of design is often referred to as a D'Appolito array, but, unlike the classic D'Appolito design, which uses third-order crossovers, the Prelude uses a second-order crossover with the tweeter wired in inverted phase.

As noted earlier, the Revised's mid/woofer has a double magnet; examining the two versions side by side revealed that this driver's diameter is also a bit greater—about 3¾" vs 3½"—and that its mounting is more flared. The drivers, made in Taiwan to Silverline's specifications, are magnetically shielded. (Given the growing popularity of flat-panel displays, which, unlike CRTs, are immune to magnetic interference, I wonder if speaker manufacturers will phase out the magnetic shielding of drivers.) The Original's cabinet had two 1 3/8"-wide rear ports: these are replaced in the Revised with a single 1¾" port. The cabinet is constructed of high-density fiberboard: the side and rear panels are ½" thick in the Original, ¾" in the Revised; the baffle ¾" thick in the Original, 1" in the Revised. The cabinet is braced at critical points, and covered with Dacron over 50% of its internal surfaces. The internal wiring is pure-copper Silverline Audio Conductor, designed by Alan Yun. In a bow to "perceived value," biwire terminals are provided, though Yun says he prefers single wiring for its coherence. I used single wiring for all my listening.

Although Silverline tests its prototypes in an anechoic chamber, Yun's approach to loudspeaker design is based on listening rather than on measurements. "Anechoic chamber measurement tells you how the equipment measures in that environment, but it cannot tell you how sweet the sound is, how smooth, and how deep and wide the soundstage."

One advantage of having a speaker as small and light as the Prelude is that it's easy to move around—quite different from the likes of the Dunlavy SC-IVs and Avantgarde Unos that I'm used to. In the end, however, the Preludes sounded best when placed in pretty much the positions I've found to be optimal with other speakers: forming an approximately equilateral triangle with my listening seat, the speakers set up along the longer dimension of my 14' by 16' room, with dissimilar distances between the speakers and the front and sidewalls. The Preludes were toed-in, though not so much as to point directly at me. After I was satisfied with their positions, I installed the supplied screw-in spikes.

The Prelude comes equipped with a grille, and the best thing I can say about it is that it's easily removed. The grille frame is made of ½"-thick MDF, with cutouts for the drivers, and the hard surface of the cutout right next to the tweeter looks like a recipe for producing diffraction. Indeed, with their grilles installed, the Preludes sounded much less open, almost muffled on top. I left the grilles off for all of my listening.

Selecting suitable electronics for a $1200 pair of speakers presents a bit of a dilemma. You want to use something that people likely to buy this speaker are likely to be able to afford, but you don't want the speaker to be handicapped by limitations in associated equipment. As it happened, I'd recently finished reviewing the PrimaLuna ProLogue Three preamplifier and ProLogue Seven amplifiers (December 2006), which are superb performers at a relatively affordable price (about $4000 for the preamp and pair of monoblock amplifiers). With the Prelude's claimed 91dB sensitivity, the ProLogue Seven's 70Wpc should have enough power to drive the speakers. I did use the Nordost Valhalla speaker cables, which cost more than the electronics and speakers combined, but I didn't want to introduce yet another variable by using something other than my reference speaker cables.

Listening, Take 1
This review is unusual in that it's really of two different speakers: the Original Prelude and the Revised Prelude. Stereophile's editorial policy is that if there's a change in the design of a product during the review period and new review samples are provided, the reviewer will discuss the performance of both the old and new review samples. That's what I do here. In this section I talk about the sound of the Original Prelude. In "Listening, Take 2" I describe how the sound of the Revised differed from that of the Original.

The Preludes' single most impressive attribute was their ability to present a sound that was BIG, dynamically and spatially. While I still had the Avantgarde Unos in my listening room, and before I began my "serious" review listening, I set the Preludes down next to the Unos, toward the center of the room, and switched the speaker cables over to them. Playing some familiar CDs at fairly high levels, I was astonished by how much the sound of these diminutive towers resembled what I was used to getting from the horns. Of course, the Preludes couldn't match the Unos in dynamic ease, and the bass didn't go nearly as low (each Uno has an active subwoofer), but there was nothing reticent or small-scale about the sound. I dare say that if I'd tried Joseph Audio's "fool the listener" trick, I might just have succeeded in getting people to believe that they were listening to the big Unos.

This impression of the Preludes producing a sound completely out of scale to their size was confirmed and enhanced when I had the speakers properly set up, with no other speakers in the room. Playing Reference Recordings' new piano recital by Joel Fan (CD, RR-106 HDCD), I was surprised by the extent to which the sound was a realistic facsimile of the scale of the sound of a live concert grand piano, and how well the Preludes were able to convey this gifted pianist's subtle touch and assured sense of rhythm. Similarly, the Preludes gave full measure to the rhythm and pace of the East Village Opera Company's rock arrangement of the overture to Mozart's The Marriage of Figaro (CD, Decca B-000518102).

The Prelude had several attributes that I think contributed to its ability to sound lifelike. The first was dynamics. Small speakers are not normally thought of as being particularly dynamic—but then, the Prelude is no ordinary small speaker. Perhaps it's those 3.5" mid/woofers, able to move quickly but having enough available cone excursion that they can produce a lot of sound without sounding distorted. I've heard plenty of small speakers that sound fine up to a moderate volume level, but if you push them just a bit further, the sound—and sometimes the speaker—falls apart. I was careful not to play the Preludes loud enough to cause damage to them or to my ears, but I did play them louder than what I would normally find comfortable, with no audible evidence of speaker distress. Keep in mind, however, that my listening room is only 14' by 16', and that Alan Yun has not managed to rewrite the laws of physics; a larger room will require more output from the speakers to reach the same sound-pressure level.

The Preludes' second major strength was their soundstaging, and the related ability of the speakers not to be the obvious sources of the sound. The Preludes were able to throw a huge soundstage, one big enough that at times I felt it was larger than the actual recording venue—a kind of "enhanced depth" effect. In fact, I think the Preludes did lean in the direction of depth enhancement. This occasionally sounded a bit "phasey," but for most recordings, especially those recorded in a sterile studio environment, it can be considered an asset.

To check the Preludes' (and, of course, the rest of the system's) rendition of depth, I played the soundstage depth test (tracks 34–42) on Best of Chesky Jazz and More Audiophile Tests, Vol.2 (Chesky JD68), which has an acoustic clicker recorded at distances of up to 80' from the microphone, with a voice announcing the distances. At recorded distances up to 60', I could discern each increase in clicker-to-mike distance, the clicker being clearly defined in space. But, as with most speakers with which I've used this test, I couldn't distinguish 70' and 80' from 60'—all three seemed to be just generally far off in the distance. Although the Prelude's cabinet is not particularly inert (with my hand on the top of a Prelude, I could feel vibration when the speaker played music at a moderately high level), this did not seem to impair the speakers' ability to project sound in such a way that it was difficult to tell that the music was coming from the speakers themselves. The Prelude was not entirely free of box colorations, but they were audible mostly at high levels.

The Prelude's tonal balance was generally neutral, but I suspect that measurements will show a frequency response less than ruler-flat (which is not to imply that a flat frequency response is a guarantee of good sound, or that a deviation from flat frequency response necessarily indicates bad sound). Bass was satisfyingly full, with even bass drums having close to the proper weight. One audiophile visitor asked where I was hiding the subwoofer! There was some emphasis in the 50–60Hz range, but not so much as to produce the dreaded "one-note bass." In my room, the bass held out pretty well down to 40Hz, as tested with the warble tones on Test CD 3 (Stereophile STPH006-2), and there was something even at 32Hz.

Voices—whose reproduction I consider to be the hallmark of midrange accuracy—had good presence, and maintained their distinctive characteristics. The treble was extended, by no means soft or rolled-off; in fact, I was at times aware of a degree of mid-treble emphasis—an extra crispness evident mostly at high levels. Overly clinical-sounding solid-state electronics would not be a good match with this speaker; however, a brief trial with the PS Audio GCC-100 (reviewed in the January 2006 issue) produced excellent results, making me think that this is an unusually synergistic combination.

Listening, Take 2
I set up the Revised Preludes in positions as close as possible to where I'd placed the Originals; the sound was similar, but with significant differences.

The Revised shared the Original's ability to produce a big sound with a dynamic ease that was hard to credit to a speaker of its size. Similarly, the Revised's bass was unusually powerful and extended for a minitower, and a bit tighter than the Original's. Like the Originals, the Revised Preludes were able to throw a big soundstage with great depth, but what I describe in "Listening, Take 1" as an "enhanced depth" effect that sounded "phasey" with some recordings was much less in evidence, with better differentiation of instrument positions within the soundstage. On the Chesky clicker depth tests, there was at least a hint of differentiation between the clicks at depths of 60', 70', and 80'.

I heard some box colorations from the Original; the Revised has thicker cabinet walls, so it would be expected to have less of a box sound, and that was generally true. Putting my hand on the cabinet when the Revised was playing loud, I could still feel some vibration, but it seemed less prominent than with the Original. (This was not what I'd call a controlled test!)

The sounds of the Revised and Original differed in two important ways. First, the new version acted as a more transparent window on the source—there was less of a "speaker sound" getting in the way. I don't know whether this was due to the new drivers, crossover, changes in cabinet construction, or some combination thereof, but the result was that the Revised sounded less like a speaker and more like the musical instruments and voices it was reproducing. The Fujitsu Ten Eclipse TD712z, which I reviewed in the January 2007 issue, remains the most sonically transparent speaker of my experience; the Silverline Prelude Revised is not at that exalted level, but is significantly closer to it than the Original.

The second welcome change was in the treble. The Original wasn't bad, but I did remark that at times I was aware of a degree of treble emphasis, an extra crispness, evident mostly at high levels. The new tweeter solved this problem, but not at the cost of producing an overly soft sound. In fact, the Revised had, if anything, a slightly more forward sound—percussion instruments with a lot of high-frequency transients sounded more prominent, though not in a harsh or fatiguing way. My recommendation not to combine the Prelude with overly clinical solid-state equipment still stands.

Asked about his approach to speaker design, Silverline's Alan Yun said he wants his speakers to sound "musical and passionate enough to convey the passion of the music to the listener." With the Prelude, I'd say he's succeeded in this aim. These mini-towers are visually unobtrusive but can produce big, nearly full-range sound, and are, indeed, capable of conveying the passion of the music. The Original Prelude was a good speaker; the Revised version is better still, in ways that are important to the listening experience. The ca-$1000 price point is a highly competitive one at which you'll find some excellent speakers, including the B&W DM603 S3, Stereophile's 2005 Budget Component of the Year ($1000/pair; reviewed by Bob Reina in the August 2005 issue), and the Monitor Audio Silver RS6 ($999/pair; raved about by Bob in March 2006). I wouldn't recommend buying any speaker without first hearing it, but if you're in the market for a speaker in this price region, or even well above, I strongly suggest putting the Silverline Prelude on your "Must Audition" list.

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