Primare has extended its power amp range with the top-of-the-line, stereo A32. This pumps out a mighty 250 watts per channel – enough for low-sensitivity speakers in large, absorbent rooms, even when high volume levels are required.
The unfeasibly heavy amplifier – you risk life and limb if you attempt to move it without help – is truly a solid lump of muscle, for which the designer has specified a mighty 2kVA toroidal transformer and 90,000µF of reservoir capacity. Internally, the amplifier is a full balanced-mode design, with single-ended inputs that are converted to balanced mode at the input for subsequent processing.
The A32 is configured as a dual-mono design internally, and employs current feedback. Active temperature compensated current sources are used instead of passive resistors, and the output stage uses no less than 16 Toshiba bipolar output devices per channel to provide current sharing. High-quality components are used throughout, including Vishay resistors, and the signal path is completely free of capacitors. However, it is not servo-controlled to mitigate effects on very low
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frequency performance caused by servo drift; instead, the DC level is set on the production line. Surface mount components and short signal paths are used throughout.
The power amp offers DC servo protection, fuses to protect against short circuits (current limiting has been avoided as it is said to adversely affect sound quality when operating with low-impedance loads) and thermal monitoring. Two separate standby modes are supported – the first, described as the ‘audiophile' mode, leaves the power supplies active; only the speaker relay and idle current are reduced, which means a quick startup at near optimum sound quality. The other, which we suppose must be described as the ‘lo-fi mode', turns off the analogue power supplies and is intended for use when the amplifier will be unused for an extended period. Naturally, this results in lower power consumption – no big power amp like this can be considered truly green, so this is a real issue. Around the back are single-ended and balanced (direct) inputs, plus two pairs of outputs for bi-wiring the speakers, while the amp's carcass sports alloy panels over a steel chassis.
