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Reviewer: John Potis
Analog Source: Rega P9 turntable, RB1000, Benz Micro MC Silver, Rega Super Elys & Garrott Bros Optim FGS cartridges
Digital source: Pioneer DV-535 DVD player/ Bel Canto DAC2
Preamp: Shindo Partager
Power Amp: Art Audio Carissa, Bryston 7B ST
Speakers: Ohm Acoustics Walsh 4 with 4.5 mk.2 upgrade, Horning Perikles
Cables: JPS Labs Superconductor and Superconductor FX interconnects and speaker wire, DH Labs D-75 digital
Power Cords: PS Power AC, Analog AC, Digital AC and Kaptovator power cords, ZCable Heavys & Black Lightnings
Powerline conditioning: Balanced Power Technology 3.5 Signature Plus with ZCable Heavy Power Cord
Sundry accessories: Vibrapod Isolators and Cones, Ultra & Heavy ZSleeves, Auric Illuminator
Room size: 12' by 16' with 9' ceiling
Review component retail: $1500/pr ($1600 in Pearl White) factory-direct with 30 day hassle-free return policy


Mike Dzurko and Audio Concepts Inc. (ACI) may just be one of the very best kept secrets in audio. In fact, ACI has been quietly (too quietly?) going about their business of fairly priced good sound since 1977. Originally more known for their DIY speaker kits than finished product, ACI nevertheless managed to develop a low-key yet fiercely loyal following. Over the years, the company has shifted focus from kits to finished products. There even was a brief flirtation with retail distribution in the early 90s when -- in 1995 and under the Dzurko Acoustics brand -- their Jaguar garnered the coveted Stereophile Class B recommendation. Eventually Dzurko found that the retail path required too much traveling and time away from his family and his chosen profession - teaching at the high school level. He retired the Dzurko Acoustics shingle and slipped back into the shadows.

Today ACI makes its modest home in Wisconsin's second oldest stone church of ca. 1867, which has been converted to suit their needs. The building is also home to a professional recording studio specializing in acoustic, electric and multimedia recordings. I doubt that many manufacturers can claim such regular proximity to real music in real time. If you find ordering a pair of speakers sight unheard to be a daunting prospect, I can't blame you. Nonetheless, you would do well to consider ACI's 30-day hassle-free return policy. 30 days strikes me as a reasonable evaluation period and the speakers sound quite good out of the box and don't take all that much time to break in.


ACI also backs the speakers with a 5-year limited warranty (excluding the usual - abuse, opening up the speaker, clipping the amp). During the first year of ownership, they additionally offer what they call TAG: Total Assurance Guarantee. It means that in case of service, ACI agrees to pay not only return shipping but two-way shipping. Both warranties are transferable to a secondary owner upon notifying ACI.


ACI has an extensive line of speakers and subwoofers intended for both multichannel and stereo use. Prices range from under a thousand dollars to about ten thousand dollars. But it would seem that the entire line revolves around the success of the venerable Sapphire loudspeaker. The first Sapphire to ever grace my system was the Sapphire III, the predecessor to the company's subsequent generation simply called Sapphire, always having been a 6½ -inch two-way. Wanting to capitalize on the Sapphire's legacy, ACI came up with a smaller 5½ -inch two-way, the second Sapphire in the line called Sapphire XL. But this Sapphire is both very different and more complex than its sibling. Dare I say more sophisticated?


One glance at the beautifully finished XL and its dual-thickness walls become evident. Composed of MDF, the front half of the braced enclosure features a front baffle and sidewalls of 1-inch and 3/4-inch thickness respectively. Midway back, the enclosure walls grows to 1.5 inches thick. The XL thus has a lot more mass than meets the eye. ACI explains that this tunes the enclosure's resonance. Overall dimensions are 12 inches high by 8½ inches wide by 12½ inches deep, the front portion being 7½ inches wide. The XL weighs in at 22 lbs. Around back is a single pair of high-quality binding posts that are stepped with two diameters and designed to optimally mate with both ¼ and 5/16-inch spade lugs. Toward the top of the rear panel resides the single 1¾" diameter bass port said to be a 4th order low-Q vent.


ACI specifies an anechoic frequency response of 48Hz - 20kHz, +/- 3dB (60Hz-20kHz +/- 1.5dB), with usable in-room bass response to between 38 and 40Hz. Also claimed is a 6-ohm low-reactance impedance with a minimum of 4.5 ohms and an 85.5dB sensitivity appropriate for amplifiers of between 35 and 200 watts per channel.


The front of the XL mounts two very high-quality drivers from ScanSpeak. The tweeter is a one-inch silk dome unit with ferro-fluid cooling, an aperiodic second chamber and a cast faceplate. The 5½ -inch long throw woofer uses a paper cone, rubber surround and a low distortion motor system with a vented pole piece. This mid/woofer and its variously sized siblings are turning up on some pretty spectacular speakers - spectacular and expensive. It's easily identifiable via the series of hand-made radial razor slashes cut into the cone and dust cap which -- once filled with a polymer adhesive -- are said to break up the driver's standing waves. Dzurko tells me that the driver is as indestructible as it is musically persuasive. He also tells me that he's made some acquaintances in the recording industry who have used prototypes of his XL and can attest to both the speaker's suitability of purpose and its bullet-proof nature. He tells me that he's received none of the prototypes back and instead gotten some additional orders. He contends that reports claim his speakers are both more highly resolved yet more listenable over those long mastering sessions than what they were replacing. They also confirm Dzurko's claims that the speakers can be driven hard. Of course, my job was to confirm these claims for myself.


In the listening room, the speakers were fairly easy to place except for an initial mid-bass hump. Rather than making the speaker fat or plodding, the location of the hump gave the speaker a quick and visceral bass presence, though only at a select frequency. I figured that having to smooth out a spike in the bass response was much easier than trying to create bass response where there was none so I paid it no mind and gave the speakers 20 or 30 hours during which time the aberration disappeared. Despite the smaller enclosure and bass driver of the ACI, I ended up placing them exactly where the much larger Krell Resolution 3 loudspeakers had been sitting. I used 24-inch lead/sand filled stands and set them
up such that the speaker baffles were 38 inches out into the room. I found both the soundstage to gel better and the speakers to disappear completely within the room when I used a fair degree of toe-in. The tweeters were 84 inches from each other and 90 inches from the listening seat. That's pretty wide spacing but the center image was exceptionally solid.


About a week before the formal evaluation period kicked off, I received the TBI Magellan VIP su active subwoofer and decided to hitch it to the Sapphire XLs. In a single afternoon, I achieved an excellent match and together they sang in sweet harmony. But when it came time to get down to business and remove the subwoofer, I was surprised by how little I missed it and by how much of the music remained.


When reviewing a small speaker with a 5½-inch woofer, some of the first questions to be answered would have to regard the bass. How much? How good? "Surprisingly enough", "surprisingly good" were the answers here. One of the first discs I played was Joe Jackson's Body & Soul [A&M CD 5000], a disc I know so well and have used as a reference so often that I no longer have to look up its catalog number. "Cha-Cha-Loco" had a surprising amount of both power and warmth and lots of texture as well as tonality. Graham Maby's bass lines seemed to lose nothing of importance. For the most part, the bass drum is not recorded in a way that captures much in the way of raw power so the foundation and drama of the music is solely represented by Maby's electric bass lines. Eventually tom-toms join these bass lines and together they ruled the stage on "Loisaida", no easy feat considering the life-like clarity and presence of the rest of the instruments on stage.


Though extremely familiar with the disc, I was particularly taken by the illuminated clarity of the XLs. The recently departed Krell Resolution 3s were slightly more robust and harmonically dense but didn't register the same air and crystalline precision. My old Martin Logan Sequel IIs did but they couldn't match the body of the XLs.


"Happy Ending" was the first cut on the disc that left me wanting for just a little more of the Krell's bygone muscle. For the price of the Krell however, you can own both the XLs and one of any number of small subwoofers that will extend bass cleanly down to at least 30Hz if not lower. But I don not want to take too much away from the XLs. They sounded both full and authoritative. They offer bass performance at least commensurate with their price, exceeding my expectations for their small woofers.