Bookshelf Speaker Reviews

Performance
Build Quality
Value

AT A GLANCE
Plus
Ribbon tweeter for wide horizontal dispersion
Kevlar cone woofer with dual-chambered loading
Multi-layered, curved cabinet
Minus
Limited bass, typical of compact monitors

THE VERDICT
The Quad Z1 monitor uses a beautifully voiced ribbon tweeter to achieve improved room coverage versus a conventional dome tweeter.

Everything you think you know about Quad comes with a curve ball. Some might associate the name with quadraphonic sound, but in fact it originally stood for Quality Unit Amplifier Domestic. That name implies a mission involving amps, and Quad does make ’em—but as any longtime audiophile can tell you, the brand is best known for its large flatpanel electrostatic loudspeakers. Some of those graying audiophiles remember Quad as a British manufacturer, but it has been under the competent and enlightened ownership of Bernard and Michael Chang of Taiwan and their International Audio Group for more than a decade.

Incidentally, IAG has a deep well of engineering resources, which enhances the performance and credibility of their brands. These speakers, per their back label, are designed and engineered in the U.K. and manufactured in China (in Shenzhen); they are marketed in the U.S. by MoFi Distribution. MoFi is the parent company of Mobile Fidelity Sound Lab, the patron saint of the audiophile vinyl reissue, which has branched out into hardware, including turntables.

Quad still makes both amps and speakers, including two models of the famous ESL loudspeaker. But there are several other speaker products and lines as well, such as the L Classic Signature, a monitor designed for Quad’s 75th anniversary; the S series, a full line with two monitors, two floorstanders, and a center; and the new Z series, a flagship line with two monitors and two floorstanders (but no center). Both the S and Z series—including the Z1, reviewed here—use ribbon tweeters. Note that the Z1 isn’t available in odd-numbered configurations for surround use. We reviewed a single pair.

Ribbon History
Quad has been using ribbon drivers since 1949, eight years before introducing its first electrostatic model. The first ribbon-driver model was the Corner Ribbon, which as the name implies had a triangular footprint that fit snugly into a corner. The ribbon driver in that historic model was too fragile and ill suited to support high-power amplifiers. The Z series ribbon is better at power handling and is much more mechanically durable. It’s a 0.5-inch-wide, 3.5-inch-tall composite ribbon tweeter (twice as tall as the ribbon in the S series). The ribbon’s shape disperses sound in a wide horizontal arc while limiting ceiling and floor reflections. The conductive ribbon is made of a composite of materials for greater robustness. It is then suspended in a strong magnetic field to maximize sensitivity. In lieu of a dome, cone, or planar magnetic tweeter’s separate diaphragm and attached electrically conductive voice coil/grid, a true ribbon tweeter combines both functions by passing the audio signal through the diaphragm material itself. Quad says the Z1 musters “our signature sound as found in the iconic ESLs.”

The tweeter is mated with a 5.9inch Kevlar cone woofer, made of woven aramid-fiber material similar to that used in bulletproof vests. The woofer (and midrange drivers in Quad’s tower models) has a doublerolled surround that is designed to control edge breakup. It’s reinforced by a double-chambered “acoustic filter” cabinet design with a port that exits the inch-thick plinth from an expansion chamber filled with resistive foam. Quad says this strikes a balance between the sensitivity and extension of a bass reflex speaker with the clarity and transient attack of a closed box. The rounded enclosure is made of multiple layers of wood fiber. It curves all the way around the back from one side of the baffle to the other, which helps defeat internal standing waves and blends more gracefully into room décor than would a boxy enclosure. The top of the cabinet has a subtle curve of its own, which is visible at the top front edge of the baffle, and a gentle rise toward the rear. Available finishes are rosewood veneer and piano black or white.

On the back, in lieu of the gold-plated binding posts you’d expect from a fancy speaker, are unusual copper binding posts with a matte gray finish. (IAG has the luxury of rethinking the binding post because they don’t buy parts off the shelf; they design, tool up, and make every part.) The four posts in strict vertical formation are biwirable and come with large, sturdy bridges that have very little flex. Specs are printed on the back: rated frequency response of 56 hertz to 20 kilohertz, rated sensitivity of 86 decibels, recommended amp power of 20 to 100 watts, and nominal impedance of 8 ohms (the manual adds a minimum impedance of 4.6 ohms). See our Test Bench for independent assessments of frequency response, sensitivity, and minimum impedance.

Associated equipment included a Pioneer Elite VSX-53 A/V receiver, Oppo BDP-83SE universal disc player, Micro Seiki BL-21 turntable, Shure V15VxMR/N97XE cartridge, and the phono stage of a Denon PRA-S10 preamp. When I used a subwoofer, it was my trusty Paradigm Seismic 110. Surround-encoded material played in 2.1 channels, with the Oppo downmixing soundtracks to stereo plus subwoofer.

Not a Paradox
The Z1 is both warm and revealing. Ordinarily, that might be a paradox; sometimes, warm-voiced speakers are hiding something, or at least sugarcoating the truth. But Quad’s ribbon tweeter mustered its golden glow while simultaneously opening a big, clear window into instrumental and vocal color and texture. It conjured bold, detailed images in the prime listening position—but also did so off axis. The result can be more physically relaxing than with some other designs because you needn’t hold yourself as rigidly in the sweet spot.