After a short period of almost eerie secrecy, Benchmark this month revealed the fruit of their latest collaboration with Californian high-fidelity and audio/visual company THX. Benchmark’s newly announced HPA4 product is pitched to serve as the 'Ultimate Headphone and Line Amplifier,' featuring a fully analogue signal path, touch screen interface and, perhaps most important of all, THX’s AAA or 'Achromatic Audio Amplifier' technology.
THX’s design input aims to ensure a realistically fatigue-free experience of listening by employing their patented feed-forward topology to reduce harmonic, intermodulation and crossover distortion from 40dB to 20dB. The result is an amplifier capable of reaching maximum output and sound pressure level, without the distortion one might expect from traditional amplifier designs. Arguably, Benchmark and THX may well have created the world’s most ‘linear amplifier’ yet.
So let’s dig a little further on the internals: the HPA4 features a true THX-888 amp design driven by a line amplifier composed of top-shelf gold-contact relays - 64 in total. Relay gain control, input selection and muting are all possible, and each relay enclosure is painstakingly timed to ensure smoothness in volume attenuation.
As promised, the HPA4’s signal path between ins and outs is 100% analogue and cleanly delivers impressive voltage to high-impedance headphones, high power/current to low-impedance headphones, 11.9 Vrms into 300 Ohms and 6 Watts into 16 Ohms.
In light of the HPA4’s rather intimidating power capabilities, Benchmark have also taken due diligence with regards to the safety of both the internal circuitry and any peripherals or headphones attached. Detection technology is in place for DC, short-circuiting, over-current scenarios and any drastic change in thermal environments, so although the amp is mighty - careful design attention has ensured it can only be used for good!
The line amplifier provides a single balanced and unbalanced stereo output, one balanced mono sum, and headphone outputs are available in the form of both 1/4” TRS and 4-pin XLR. Whilst both headphone channels will deliver peak performance, Benchmark opt to recommend the XLR route where possible due to its lower contact resistance spec.
In operation, Benchmark’s HPA4 touchscreen offers easy access to a wealth of functionality including balance control, input level offsets, screen dimming and advanced feature locking. A rather handy help screen function is also accessible to explain each of the functions on offer.
As an optional extra, users can also invest in Benchmark’s Remote Control which allows access not only to the HPA4’s control panel but also operation of other Benchmark units used in the same system such as the DAC2 or DAC3.
In keeping with Benchmark’s existing and legacy product ranges, HPA4 features a compact footprint, a choice of black or silver milled faceplates and thick 'built-to-last' aluminium panelling. The neutral design ensures it as a great fit both for other Benchmark counterparts and third party components alike.
For details on lead-times, availability and pricing, contact SCV for more information.