Integrated Amplifiers

British company Ferrograph, as its name suggests, has its origins in the production of tape recorders. After the Second World War it successfully marketed a series of professional machines based around the sturdy Wearite deck. Having mastered this most difficult of components, it would have been relatively straightforward for Ferrograph to diversify into other lines. But its first integrated stereo amplifier is one of the most interesting.

In some ways the AX-5 represents a distillation of Ayre’s ‘purist’ philosophies, as it employs both the company’s ‘Diamond output circuit’ and the elaborately-designed volume control trickled down from its flagship KX-R Twenty preamplifier. In the fully-balanced zero loop feedback AX-5 integrated, Ayre eliminated the preamp stage altogether and simply made the gain of the power amplifier directly adjustable using VGT (Variable Gain Transimpedance). The volume knob on the right of the fascia acts as an encoder to control a pair of motor-driven Shallco silver-contact rotary switches (one for each channel, conjoined using toothed belts), each of which contains dozens of hand-selected, low-noise resistors. Volume level can be adjusted over a range of 69dB in 46 steps of 1.

Exposure Electronics was founded by John Farlowe in 1974 and has remained committed to two-channel music reproduction. The company is largely famous for its big blackpre/power amplifier combinations of the 1980s, when it sold to people who wanted punchy solid-state amps that sounded smoother and creamier than rival Naim products. Nowadays, the sound hasn’t changed much but the size has, and most of its wares are more affordable products such as this one – Exposure’s top integrated. The 3010S2 series comprises a CD player, mono and stereo power amps, a preamplifier and a phono amp.

The TA-1120 stereo amplifier was a step-ahead design which combined power, quality, reliability and compactness in a way that had not been seen before, but which in a few years would become ubiquitous across the ranges of Japan’s major hi-fi brands. In 1968 the original TA-1120 was replaced by the TA-1120A, as tested here, the addition of a headphone socket and the removal of a ‘safety’ indicator light being the only obvious external clues as to which model is which. Revisions were also made to the preamplifier circuit. The main selector lever gives a choice of phono 1 (MM) or tuner, along with a central position that selects a rotary control giving four further options, eg, mic, tape head, second MM turntable and line-level auxiliary input, which can be used to connect a CD player.

The Editor’s review briefing included the warnings: ‘It’s 29kg – you may need help in unpacking it’ and ‘The S-550i is a remarkably dense amplifier, probably the most self-effacing yet monstrously powerful integrated we’ve ever tested. ’ This new flagship integrated, replaces the FBI while the S-300i remains as Krell’s entry-level integrated at £2795. The S-550i is a true ‘big brother’: the sonic resemblance is uncanny save for a brutal power delivery. While the front panel suggests minimalism, that’s only because all minor settings are relegated to a menu system, eg, balance setting and input trim, which can also be accessed by the full-function remote.

If proof were needed of Bryston’s mettle for embracing the modern world beyond purist two-channel analogue pursuits, it’s the B135 SST2 C-Series Integrated Amplifier. While the unit reviewed here is two-channel, purist and analogue, it can be fitted with a DAC module for £1575 that adds two coaxial and two Toslink inputs. Other options include a £500 universal remote and an MM-only phono stage for £650. Bryston offers neither MC nor USB.