Integrated Amplifiers

Icon Audio's new Stereo ST30SE amplifier makes use of beefy KT150 output valves in an effort to overcome the traditionally low power of SE tube amps. Does it succeed?

The single-ended valve amplifier is still something of a niche product. Low power outputs and often equally low damping factors mean that very careful system matching, plus sensitive loudspeakers, are a prerequisite if you are to hear such designs give of their very best. However, the UK's very own guru of all things thermionic, David Shaw of Icon Audio, has decided to address these issues with his £2299 single-ended Stereo ST30SE, an integrated amp having, shall we say, a tad more welly, thanks to it being equipped with KT150 output valves.

Offering all the functionality of full-sized components, this petite five-part '90s system took micro to the max, spawning imitations industry-wide. How does it sound today?

The first time I saw a JVC UX-1 it was pictured on the side of a bus. The image was part of an ad that carried the simple message 'All features, Great, and Small'. And this turned out to be true, for the UX-1 micro system had every function imaginable, sounded like 'proper' hi-fi and was tiny.

Debate that’s been raging since the dawn of hi-fi, Integrated vs Separates boils down to this: the former’s benefits over the latter include the removal of a pre-to-power cable connection, the need for one less AC outlet, less shelf space and – above all – the knowledge that the two sections are optimised for each other. Separates, however, counter with truly dedicated power supplies for each section, as well as isolation of the pre and power amp stages for less potential for undesirable interaction. Traditionally, the higher you go up the price scale, the more likely you are to opt for separates. Over the decades, milestone integrateds would appear that upset the formula: Sugden’s A48, specific models from Rogers, McIntosh, AR, et al.

Yes, those valves – made in-house – really are a foot tall! And they radiate substantial heat once the SXI has been powered up for a few minutes, but KR Audio’s amplifiers are beautifully engineered. The company is based in Prague, founded by electronics engineer the late Dr Ricardo Kron in 1992. It’s a boutique firm of only a dozen or so people – skilled artisans who blow the glass and hand-craft the tubes. Such is the transparency of KR Audio’s Kronzilla amplifiers that at least of couple of German recording studios use them in mastering suites.

Very big in the Far East since 2005, Line Magnetic offers a comprehensive range of tube-based disc players, DACs, phono stages and amps. Here's the entry-level integrated

We may now live in an age of digital and streaming, but the number and sheer variety of valve amplifiers on offer seems to be on the increase. Perhaps more remarkable are those designs that unashamedly hark back to a previous era, attempting to keep it alive by the use of modern technological twists. One of the main proponents of this philosophy is Chinese company Line Magnetic, the £1699 LM-34IA integrated reviewed here being just one of a wide range of its amps inspired by famous designs of the past.

The style may be ‘retro’, but this powerful integrated amp from a Far East legend is no exercise in nostalgia: it lacks fashionable digital inputs, but has serious sonic appeal

OK, so it may help explain the whole ‘vinyl revival’ thing, from portable record players with greater tracking weight than a Caterpillar bulldozer to supermarket own-brand LPs, but looking to the past will only get you so far. Forget all that longer summers, colder winters and ‘jumpers for goalposts’ stuff: even nostalgia’s not what it used to be. Products must stand on their own merits in today’s competitive market.

High-end headphone amps for connoisseurs of cans require total adjustability – has Manley Laboratories delivered the goods with the Absolute Headphone Amplifier?

Veteran makers of headphone amplifiers for studios, Manley Laboratories is taking on the extreme high-end of the domestic genre with a £4500 unit – the Absolute – that marries audiophiles' sonic requirements with the total control demanded of professionals. Company CEO Eveanna Manley says, bluntly, 'Our goal was simply to produce the most awesome-sounding and sonically flexible vacuum tube headphone amplifier!'.