Trilogy

Trilogy Audio Systems has been designed by one person since 1990. Nic Poulson trained with the BBC in broadcast engineering in the eighties, founded Trilogy in 1990, and remains the principal designer of every product the company makes. The corporation's standards left a mark: the way to achieve true quality is to strive for excellence in every area and accept nothing less. Trilogy is one of the very few British owned, British built manufacturers of fine audio, and the work is done back to first principles — identifying the fundamental questions at the core of each design issue, then optimising each electrical element rather than improving on what already exists.

The engineering runs along a few consistent lines. The 6H6П valve is used throughout the range for its extremely linear gain, high transconductance and high current properties, and in several products it operates in a grounded grid configuration that lets the tube produce even lower levels of distortion. Choke input power supplies are unusual today, largely for reasons of cost and space. Trilogy specifies them anyway: a large choke placed between the rectifier and the smoothing capacitor bank makes the current draw from the mains transformer almost a continuous sine wave, instead of a series of current spikes at twice the mains frequency. The stress in the power supply components and the noise produced fall away with it.

Every Trilogy power amplifier uses a compound output stage. A small linear MOSFET controls the loudspeaker, and a bank of bipolar transistors augments it with the current a demanding load requires. The result is delicacy unattainable with a MOSFET-only output stage together with enough output current to genuinely control the speaker. Where balanced operation earns its complexity it is used — the 925 and 995R are bridge amplifiers and make full use of it; the 993 and 994 are not bridge designs and so are not given a differential feed for its own sake.

The casework is part of the engineering. Machined panels, lids and side panels add mass and damp vibration. Heatsink fins vary in depth, width and spacing to reduce the main resonance to a minimum, and the high mass holds the output devices at close to constant temperature. K Material, an expensive and non-resonant material, is used for the feet on all larger products. Binding posts are pure copper Mundorf. The 906i is hand made exclusively in England; the 931i is assembled entirely by hand in Trilogy's UK workshops.

The control layer is Trilogy's own. TASlink is a proprietary link between Trilogy components that synchronises switching and carries information such as amplifier temperature and real-time current delivery to a large red dot matrix display, adjustable across nine brightness levels or set to track the ambient light. The firmware is driven by a rotary encoder with enter and escape buttons, covering volume and balance alongside timing functions, per-input naming, source level trimming and more. The Personal Remote Control is machined from billet with ball bearing buttons.

The Trilogy range — integrated amplifiers, preamplifiers, stereo and mono power amplifiers, phono stages and headphone amplifiers — is available through Alma East and Alma West.