Verity Audio Sarastro II

The Sarastro is a two-cabinet, floor-standing, three-way, bass-reflex loudspeaker belonging to Verity's extended range series. The top cabinet features a wide-spectrum midrange and proprietary ribbon tweeter that's built in-house. The bottom cabinet houses an impressive bass-reflex rearward woofer. Both cabinets are isolated by a solid aluminum platform coupled with special elastomers and the bottom cabinet is floor-coupled via Verity's Mechanical & Airborne Sound Isolation System (MASIS). The Sarastro exhibits a high 93 dB SPL 1 watt/1 meter sensitivity and inherits from the best Verity Audio technologies.

The cabinets themselves, made of 1"-thick MDF, are very rigid, as are their extensive layers of internal bracing, and are coated with polyester lacquer in a piano-black finish (also available, at extra prices are finishes of high-gloss silver, makore, or quilted big-leaf maple). The assembly is coupled to the floor by adjustable, tight-locking spikes of solid brass and stainless steel.

The woofer and midrange drivers are custom-built by the Danish firm Audio Technology, but the Sarastro's design and the philosophy behind it come from Verity's proprietors, Bruno Bouchard and Julien Pelchat, music-loving Quebecois engineers who have spent much of their time the past two decades doing research and development into loudspeaker behavior.

The Sarastro II's midrange driver uses an underhung voice-coil-ie, a coil that's shorter than the magnet which is said to maximize linearity. A copper Faraday ring on the coil's formers keeps the magnetic field focused in the gap containing the voice-coil, to prevent variations in the signal from producing variations in the field's intensity. Keeping this driver under control is a delicate task, as it covers an unusually wide bandwidth, from 150Hz to 5.5kHz. The idea is, first, to keep the music's midrange as smooth as possible, and second, to free the ribbon tweeter from the burden of reproducing fundamental tones (the highest note on a piano sings at about 4.2kHz) and letting it do what it does best: emit high frequencies, which it does across six octaves, all the way up to a claimed 60kHz.

It's the speaker's new tweeter that led Verity to upgrade the original Sarastro (which Michael Fremer reviewed in the March 2005 Stereophile, Vol.28 No.3). The older version was also a ribbon design, but the tweeter in the II, designed and manufactured by Verity, incorporates a reworked magnet, a wider ribbon element, a suspension that handles power more efficiently, and a redesigned front plate to better match the dispersion of the midrange driver. However, all of these changes required adjustments to both sets of crossovers, the bracing and air flow inside both cabinets, and all the internal wiring (which is now solid silver with OFC conductors suspended in a Dual Micro Mono-Filament design).

But it's the woofer 11" in diameter, weighing about 35 lbs, with an underhung 4" voice-coil and a 4" flared port of aluminum that is the most controversial and potentially problematic element of the Sarastro II. It's rear-mounted. (Verity's smaller Parsifal lets you turn the woofer cabinet in either direction, to fire forward or back, but there's no such flexibility with the Sarastro.) Most speaker designers try to minimize, or simply ignore, the effect of room reflections. But Bouchard and Pelchat have found that almost all rooms boost bass to some degree, so the Sarastro is designed to exploit these effects"to integrate smoothly and accurately with the room," as Verity's literature states. At the same time, the woofer alignment uses Bessel tuning, which initially rolls off gradually before reaching its eventual 24dB/octave behavior that supposedly "compensates for" the bass boost that a room provides. With proper speaker placement, Bouchard and Pelchat claim, the Sarastro II's bass can extend flat to below 25Hz.

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Three-way, dual-enclosure, floorstanding loudspeaker.
Drive-units: 2"-tall aluminum-ribbon tweeter, 6" doped polypropylene-cone midrange,
11" polypropylene-cone woofer.
Crossover frequencies: 150Hz, 5.5kHz.
Frequency range: 25Hz-60kHz.
Sensitivity: 93dB/2.83V/m.
Normal impedance: 8 ohms nominal, 4 ohms minimal.
Dimensions: 47.5" (1210mm) H by 14" (350mm) W by 20" (505mm) D.
Weight: 150 lbs (68kg).