A thesis, in its purist form is an intellectual proposition in which something is “put forth”. The new thesis preamplifier, power supply, phono preamp and power amplifiers have been designed to be the superclass of Heed products, which will put the music forth. The unconventional and almost heretical approach to circuit design taken by the engineers is far from the accepted norm, in the pursuit of a life-like sonic presentation to render the music’s full complexity, atmosphere and tension.
Thesis, for all it’s unconventional design, is no bare-bones purist creation in a home made box. It is a range of cutting edge 21st century products, using only the highest quality components and very carefully designed circuitry installed into precision engineered, “retro-futuristic”, cases of a quality normally only found in far costlier high end audio.
The range is centred on the thesis α (alpha) preamplifier, which features two analogue and four digital inputs including S/PDIF, TOSLINK, BNC and USB. All inputs are selectable via the new remote control handset, which also controls volume and muting. The twin capacitor-coupled output stage allows the use of long interconnect cables for connection to two sets of power amplifiers for bi-amplification. The external thesis π power supply unit powers the analogue stage of the thesis α, which is a new design from scratch.
Building on the renowned Heed Dactil 2.1 and USB 2.0 Audio modules used in the company’s Obelisk DA digital to analogue converter, the digital section of the preamp is modular in design to allow future upgrades to be made.
Thetwin power supply thesis π (pi) can feed the thesis α preamp and thesis φ phono stage simultaneously. Independent sections, each with dual regulated power supply rails and high-grade components, custom made by Airlink and Mundorf to Heed’s specifications, ensure an absolutely clean and stable power delivery. Massively over-specified for the purpose, the thesis π provides a smooth and effortless performance even when pushed to its limits.
For vinyl connoisseurs, the thesis φ (phi) is a no-compromise phono preamplifier for use with top-class turntables requiring very low noise characteristics, huge dynamic range, plenty of headroom and an extremely smooth frequency response. Also powered by the thesis π PSU, the thesis φ is a twin circuit design, independently catering for both MM (moving magnet) and MC (moving coil) cartridges. Two turntables may be connected simultaneously and cartridge matching is highly user customisable for gain and impedance via the easy to access rear panel jumpers.
The musical muscle comes from the thesis ω (omega) monobloc power amplifier. In true Heed fashion this is an AC-coupled device that drives loudspeakers in a similar way to valve power amplifiers, but without the inherent problems related to valves. Although its topology is similar in some ways to a valve design, the thesis ω is a firmly solid state design, but one which gets around the sterile and lifeless performance of most solid-state devices. AC coupling is used in preference to the more common DC coupling to produce a much more natural and less “cropped” decay of tones within the music. The thesis ω demonstrates a synergy of solid-state stability and the finesse and “live magic” usually only achieved with 300B triodes. The generously over-sized power supply, with a core that will not saturate, delivers a totally silent operation and up to 160W continuous power or capability of driving loads down to 1.6 ohms.
Launching the thesis, Heed’s marketing and sales director Alpar Huszti says, “Music reproduced by the bulk of higher end audio equipment is often described as ‘precise, neutral, or uncoloured’. Comme il faut. High fidelity note for note. But shouldn’t it be ‘thrilling, spellbinding, or enchanting’? We immerse ourselves in music because it touches our soul, mesmerises our senses, thrills and captivates us. If we want to rekindle this fascination, we have to create true wonder-weapons that make music ‘walk on the wild side’ again.” He continues, “To achieve this, the new thesis range, with its characteristic visual appearance and unique life-like sonic presentation, pulls clear of the familiar pack of sadly unimaginative audio products to stir emotions in the Heed tradition. Thesis is living proof that it is possible to create audio equipment that makes the recorded music engraved in bits or grooves, come alive.”