Pre/Power Amplifiers

There's so much functionality under the bonnet of Bryston's BR-20 that you might wonder where to start. I would suggest the manual – this £7500 networked USB DAC/preamplifier isn't, it must be said, the most instantly intuitive of system hubs I've ever auditioned. But the effort is worth it though, because what the BR-20 can do, and how it does it, is quite special.

Nothing if not ambitious, Cambridge Audio's Edge series first broke cover three years back as part of the company's 50th anniversary celebrations. It took its name from Gordon Edge, one of the company's founders and the brains behind its first product, the P40 amplifier. Designed to take on the best in high-end audio, these Edge separates also serve as 'halo' products for the company's lower-tier ranges.

With the Valve Amplification Company, aka VAC, now 30 years old, it qualifies as a stalwart of the 'third wave'. The first was, of course, the original golden age generation of Marantz, Quad, McIntosh and others of the 1940s and 1950s, while the second wave hit in the early 1970s with Audio Research, EAR and other tube revivalists. VAC arrived at the point when tubes were demonstrably here to stay, Kevin Hayes founding the company with his father in 1990. He was, and remains, resolutely focused on the high-end, as this pairing's £69,000 cost attests.

The best of both worlds' is an oft-used rallying cry in the hi-fi industry, rolled out to extol the virtues of everything from compact loudspeakers with big bass output to digital network players with phono stage inputs. It's also the self-proclaimed raison d'être of PS Audio's Stellar M1200 monoblock amp. Sold in pairs for £6000, this recent addition to the Stellar range combines a high-power Class D output stage with Class A vacuum tube input, in pursuit of both efficient speaker-driving muscle and spine-tingling musicality.

It's always intriguing to see how a company reacts to the realisation that a technology it has championed is reaching its sell-by date. This was the situation faced by Yamaha in the late 1970s. Since the middle of that decade, its top-end products had made use of Jun-ichi Nishizawa's Static Induction Transistor – more commonly known as the VFET – to great effect. This led to the development of designs such as the B-1 and B-2 power amplifiers, and C-1 preamplifier, all of which are still held in high regard.

You'll have to examine the £5399 Michi M8 monoblock power amp very closely to see how it differs from the company's S5 stereo model, reviewed previously alongside the £3299 P5 preamplifier [HFN May '20]. The two are the same price and size, look identical and have much the same 'ask a friend to help' mass. In fact, the M8 weighs marginally less than the S5, at 59.1kg – the difference presumably accounted for by the need for two-channel inputs on the stereo amp whereas the mono version has only single-channel connections, on both balanced XLR and unbalanced RCA sockets.

The long awaited Carver Cube power amplifier is at last available in the UK. Bob Carver, its designer, is not a particularly well known figure in the UK but most people have heard of Phase Linear, which was founded by him, and he also designed its range of products. His special interest has been in high-power amplifiers, with the 400 B and 700 B Phase Linear models now audio legends.