The HP4 uses 6SL7 valves, properly matched to the load through de Paravicini’s renowned transformers, to deliver nearly 1W of high quality, low distortion power into high or low impedance headphones. The output circuit configuration uses de Paravicini’s ‘Enhanced Triode Mode’, as employed in the highly successful V20 and 859 integrated amplifiers, while the input is also transformer coupled, giving the flexibility to accept balanced or unbalanced signals from the preamplifier.
For the greatest user convenience the HP4 has its own volume control, while input signals can be independently switched through to the power amplifier for headphone and/or loudspeaker listening. A pair of headphone sockets are supplied on the front of the unit for both high and low impedance headphones. As with all EAR products, reliability is paramount and valve life is in excess of 10,000 hours