Pre/Power Amplifiers

The Virgo preamplifier and Centaur monoblocks reviewed here are models from Constellation’s ‘economy’ Performance range, yet total £72,500. As for Reference prices, we shudder to think… While a pretty enough design, the Virgo is rather anodyne, its greyness John Major-like. A plain-Jane outboard power supply feeds it via two umbilical cables, connecting at the back where you find rows of both XLRs and phono sockets for every input and output – four sources, two sets of outputs and RS232 and USB inputs for networks and firmware upgrades. At the front, the central panel’s 432x230-pixel screen is flanked by rotaries for balance and volume, while other operations are accessed through menus activated by a row of buttons under the display panel.

You want big valves? Really big? NAT has cooked up a monoblock with a mortadella-fat QB 5/1750 tetrode, and a preamp worthy of the honour. Enter Utopia and Transmitter Any reservations I may have had about Eastern European amplifiers were put to rest by the NAT Se1 MkII reviewed in Aug ’10. It was time, I thought, to stop treating the former Communist Bloc as if it were the equivalent of China circa 1993. If anything, countries like Serbia, Bulgaria and others under the grip of the Commies for a half-century had a much better chance at conquering the high-end than the Chinese did, because they had greater hands-on experience.

Anniversary edition of the Reference five splits into two boxes for improved performance Released to commemorate the 40th anniversary of the company’s Reference preamp, the Anniversary Ref 5 promises to address the few solutions not available in its recently unveiled single-chassis version. This two-chassis model sees the valve power supply relegated to a box of its own and, being a true dual-mono layout, two fat umbilical cords connect it to the chassis. Under the lid can be found an all-valve, zero feedback, pure Class A circuit employing four 6H30 triodes per channel, again dual-mono, while mounted on the bottom of the main board are four massive custom Teflon coupling capacitors, weighing around a kilo apiece. Each valve is fitted with a now-familiar damping ring; the main circuitry is fitted to a large mother board; daughter boards deal with the front panel and the socketry.

The latest Levinson product is a consummate music maker New electronics bearing the Mark Levinson badge don’t appear too often. When they do, the world of high-end audio expects them to be exemplary. In producing its first switching amplifier, the ML design team has been able to scale things down to (almost) manageable proportions. The benefits of Class D amplifiers include increased efficiency enabling greater power output while requiring less heat dissipation in smaller, lighter and more affordable packages.

Dan D'Agostino returns with a product half amplifier, half sculpture, all genius With his new company’s first product, the Momentum Monoblock Power Amplifier, Dan D’Agostino hopes to re-write the rules of solid-state amplifier design. Most notable is a concern for green issues, by addressing the amp’s power consumption when not in use. It’s a claimed 1W – not bad for a 300W amp that thinks it’s a kilowatt. Running in Class AB, and merely warm to the touch after a long session reflects a cooling system which provides much of the Momentum’s visual presence: solidcopper bars (venturis) that form the amplifier’s flanks.

The first solid-state Quad remains a classic of the genre Exemplifying all that was admirable in British hi-fi, the 33 preamp (£43) and 303 power amp (£55) were Quad’s first commercial solid-state offerings, the company having waited for the new-fangled transistor to settle down before embracing it in 1967. It was in many ways ‘a solid-state Quad 22’. Any previous customer would have immediately recognised the control locations, the flushmounted rotaries, the balance control under the volume control, the press buttons that also offered Quad’s unique, fully cancellable filter and tone controls and RIAA selectors. In size, the 303 and the Quad II power amps were nearly interchangeable.