Hifi Pig

Audiolab has redesigned its most famous component to deliver an entirely new level of performance. The 8300A is the latest in a long line of Audiolab integrated amplifiers that began in 1983 with the 8000A which Audiolab claim is ‘one of the most influential British audio products of all time.’ The original 8000A was the quintessential ‘step-up’ amplifier, delivering build quality, reliability, functionality and performance that were a clear level above the classic ‘budget’ amps of the time. It proved a tremendous success, its crisp, clean sound quality offering an upgrade path well trodden by music fans in the UK and beyond throughout its 14-year lifespan. The 8300A is the second component to be announced from Audiolab’s new 8300 Series, hot on the heels of the 8300CD CD player/DAC. While the 8300CD is a careful evolution of its predecessor, the 8300A is a full redesign of the product it replaces, the 8200A. Its external design is clean and simple; still recognisably Audiolab, albeit sporting the updated 8300 Series aesthetic. Inside, the changes are more radical.

According to Jan Ertner, who led the 8300A development project, the new amp represents “a fresh approach to the same challenge: genuinely ‘high-end’ audio amplification in a single box, delivered to the end user at an affordable price”. Its design enables it to adapt to its user’s evolving requirements, offering three distinct operational modes: integrated amplifier, preamplifier or power amplifier, the latter enabling it be partnered with a surround sound processor in a high-performance AV system.

At the amp’s heart is a powerful dual-mono power amp section, delivering 75W per channel into eight ohms, with a maximum current delivery of 15 Amps into difficult loads. This is significantly more powerful than the outgoing 8200A, which was rated at 60W into eight ohms. The output stage of the discrete power amp circuits uses a CFB (Complementary Feedback) topology in combination with conventional emitter follower circuitry. The CFB stage offers superior linearity and ensures excellent thermal stability, as the idle current is kept independent of the temperature of the output transistors. Using an emitter follower in combination with the CFB stage is an efficient way of increasing the current ability of the amplifier without compromising the advantages of the CFB circuit. Having the emitter follower deliver additional current only when needed allows for a simpler current-limiting arrangement, which can be voltage independent. Audiolab calls this ‘Active Current Drive’, where the current limiting is under microprocessor control and programmed to allow the amplifier to supply high currents (+- 15A) into complex loads on par with amplifiers that are bigger and more powerful on paper. A 300VA toroidal transformer supplies the two mono amplifiers using separate secondary windings, followed by 2x15000uF reservoir capacity per channel (60000uF in total). The preamp section is kept as simple as possible to maintain signal purity, with line input signals simply passing through a unity gain buffer and a precision analogue volume stage. The latter covers the range from-80dB to +8dB in steps of 2dB, 1dB and 0.5dB (step resolution increasing with volume position). Much effort has gone into the physical layout of the 8300A’s circuitry, keeping the sensitive preamp section as free from noise interference as possible. This, plus the use of independent power supplies for critical circuit stages, helps to deliver performance on par with high-quality two-box pre/power amp systems. The inclusion of a phono stage is another important enhancement – the 8200A eschewed this facility, but the 8300A brings it back to capitalise on the current vinyl revival. Turntable users will appreciate the care with which this new stage has been designed, fed by its own power supply and delivering a high-quality, low- noise performance with both MM and MC cartridges, thus removing the need for an off-board phono stage.

Externally, the most obvious addition is an OLED display in the centre of the amp’s fascia, showing volume level, input selection, mode of operation and MM/MC phono setting. This display reflects the design of the 8300CD, helping to ensure that Audiolab’s new 8300 Series integrated amp and CD player/DAC are a perfect match for each other both aesthetically and functionally. Around the back, five line-level RCA inputs nestle alongside the phono input, plus a balanced XLR input for suitably equipment source components (including the 8300CD). Two pre outputs, a power input, a 12V trigger loop and a full set of loudspeaker binding posts for bi-wiring complete a comprehensive array of connectivity options.

The Audiolab 8300A integrated amplifier is available from October in a choice of silver or classic Audiolab black, with an RRP of £899.95.