Bookshelf Speakers — SVS Sound Ultra Evolution Bookshelf

The Ultra Evolution Bookshelf is the two-way stand-mount of SVS's Ultra Evolution series, the top loudspeaker line from the Ohio manufacturer that built its name on subwoofers. The series replaced the original Ultra range and was designed to serve both two-channel music systems and home cinema, where the Bookshelf can act as a main, surround or rear speaker.

Key specs that matter

It uses a 25 mm (1 in) diamond-coated aluminium dome tweeter and a 165 mm (6.5 in) glass-fibre composite woofer, with a crossover at 1.8 kHz. Frequency response is 40 Hz to 40 kHz (+/-3 dB), sensitivity is 87 dB (2.83 V/1 m, full space, 300 Hz to 3 kHz) and nominal impedance is 6 ohms. The recommended amplifier range is 20 W to 150 W. Each cabinet measures 378 x 220 x 285.7 mm and weighs 8.6 kg.

Engineering and use context

The tweeter dome is aluminium with a diamond-like coating grown by vapour deposition, which stiffens it and pushes its first break-up above the audible band. In front of the dome sits an Organic Cell Lattice Diffuser, a semi-random structure derived from organic cell patterns and optimised with finite element analysis, which protects the dome and spreads high frequencies more evenly off axis. Silver tinsel leads carry the signal to the voice coil. The woofer has a long-stroke motor and suspension for high output, a precision-cast aluminium-alloy basket for alignment and heat dissipation, and a vented aluminium voice-coil former that reduces air compression at high drive levels. The cabinet geometry is time-aligned, setting the drivers at different depths so that their acoustic centres are equidistant from the listener. The chamfered front baffle reduces edge diffraction. The crossover uses a heavy-trace circuit board, and two pairs of five-way terminals are fitted. Grilles attach with neodymium magnets, and finishes are piano gloss black, piano gloss white and black oak veneer.

Pairing

The speaker is an easy load for most AV receivers and stereo amplifiers of 50 W or more. Its bass extension makes it usable full range in smaller rooms, while in a home cinema it integrates with a subwoofer at an 80 Hz crossover. SVS's own SB and PB subwoofers are designed as its partners. The dual binding posts let a stereo amplifier drive the tweeter and a second amplifier the woofer in a bi-amped system, and the magnetic grilles leave no visible fixing holes when removed. Shipped as a pair, the speakers weigh 18.9 kg boxed.

Alternatives

SVS's Ultra Evolution Nano is the smaller stand-mount of the same series for tighter spaces.