Of conventional proportions, the Power Plant is not as slim or as button bound as most T+A components and is a little friendlier too, thanks to its smoothly rounded edges. Internally, the main feature of note is the use of a switch-mode PWM output stage, apparently of some sophistication and of proprietary design. The output stage is based on the ‘valve-based’ design of the power amplifiers in T+A’s TCI active loudspeakers.

In T+A’s own words, "the preamp section of the power plant has the same circuit as the R-series preamp P1230R and the PA1230/1530 integrated amps."

According to the literature, it also has a high- quality four fold ALPS motorised potentiometer for volume control and – as with all its amps – hermetically sealed gold contact relays. "The power amp section does not use integrated 'off-the-shelf' IC-amps or the widely used B&O ICE-power based modules. The amp consists of a PWM modulator built around an Analog Devices AD 829 op-amp. PWM output signals drive the current (up to 50 Amps) output section which is equipped with latest generation high-speed IRFB4020MOSFETs.

The power supply is an analogue design based on a big-shielded high power torroidal transformer, with high capacity low impedance smoothing capacitors".

T+A goes on to say that the switch-mode output stages generate the output signal as a large number of very short positive and negative signals. "Our new switch-mode output stages have been developed entirely in-house and include output stages of discrete construction, equipped with the latest, ultra-fast MOSFET transistors and high-power intelligent driver modules. The modulator is analogue, although the output stages feature analogue feedback circuitry designed to compensate for the effects of voltage fluctuations in the mains section, as eliminating the power supply induced signal distortion is otherwise unavoidable."