Pre/Power Amplifiers

'There are about a dozen conceptual ideas behind the Halcro topology that you won't find in other amplifiers', says Managing Director/CEO Peter Foster. Fully balanced/symmetrical operation is not key to the Eclipse's incredible technical performance, however.

'We don't strive for symmetry as some designers do', confirms Peter, 'it's just not achievable when you get down to the transfer characteristics of the devices. Our output stage is not especially radical. We use complementary FETs and a reasonably high quiescent current, but it's designed to be synergistic with the more innovative stages that come before it, and the overall distortion compensation topology'.

Halcro remains coy about levels of nested feedback within the Eclipse and how it has achieved such a vanishing low output impedance. 'The bandwidth of each internal stage is significantly higher than conventional amplifiers but the bandwidth of the output stage is only marginally so', Peter swerves...

Meanwhile, a new preamp is in the wings using Eclipse-inspired circuitry, but there's no launch date as yet. 'We are also developing a range of more affordable amplifiers', Peter reveals, 'and these will sit below the Eclipse in performance but will retain a lot of the qualities that make Halcro stand out. The electronics are largely complete and we are at the stage of getting prototype casework made. I also have a couple of unusual DAC concepts that have been rattling around in my head, but these are a long way off being validated'. As ever, watch this space! PM