Pre/Power Amplifiers

The latest circuit revisions to have worked their way into the MxV and, now, the Relentless amplifiers not only include the use of identical/symmetrical On Semi transistors in both the (high voltage) driver and main power output stages but also a general relaxation in corrective feedback, courtesy of these stages’ generally improved linearity. This has been achieved without compromising overall bandwidth – the response is broadly unchanged – but juggled alongside a slight increase in odd-order distortion from, for example, 0.0015% in the Relentless to 0.021% in the ’800 at 1kHz/10W/8ohm, as well as an increase in output impedance from 0.04-0.06ohm to the 800’s 0.07-0.1ohm (all 20Hz-20kHz). Reduced feedback is also reflected in its thermal tracking, so where the Relentless’s distortion decreased from 0.006%/1kHz/10W (cold) to 0.0035% over an hour and then 0.0015% as the amplifier slowly warmed from 20oC to 45oC, the 800’s THD increases with temperature from 0.011% (cold) to 0.017% over the first 30mins [black trace] and then to 0.019% [red trace] once its thermal latency is almost entirely resolved (~40oC) after a few hours. PM