With the much-lauded PH5 phono preamplifier, Audio Research set a new benchmark for phono performance and features at its modest price. Now, phono enthusiasts have a new and even higher performance option: the all-new PH7 stereo phono preamplifier.
The PH7 takes advantage of more recent technology developed for products like the landmark Reference 3 preamplifier, and uses an all-vacuum-tube audio stage with four 6922 twin triodes. Regulation of the power supply is also vacuum-tube, using three 6H30 triodes. Output coupling caps are the costly, advanced types proprietary to Audio Research, with power-supply energy storage more than three times that of the PH5. Circuit board material, power transformer design and size, and other components have been exactingly selected to boost phono performance to a previously unachievable level.
The PH7 has 57.5 dB of overall gain, and features one pair of single-ended inputs and outputs. Full remote control is provided for all functions, coupled to an easily readable front-panel vacuum-fluorescent display. The display shows all selected functions including loading (47K, 1K, 500, 200, 100 ohms), as well as accumulated hours of operation. Display intensity can be adjusted to one of eight levels, plus off.
The PH5 has won renown for its inspired musicality, unerring tonal balance and realistic dynamics. The PH7 dramatically improves upon these virtues - and then some. Soundstage dimensions are of course scaled up in width and depth, with even more solid image specificity. Tonal shadings and microdynamics - so important to the believability of any musical rendition - are much more vivid, thanks to extra power-supply muscle and a low noise floor. Perceived frequency extension is much improved, with highs silky yet vivid, while deep bass notes are carved out with slam and real tonal definition. PH7 purchasers have yet to discover what their table, arm and cartridge setups are truly capable of! And every vinyl collection will take on new life and reveal new meaning as it is played back record-by-record through the amazing PH7.