A.C.T. One Evolution Press Kit

GEOMETRY SERIES

The name A.C.T. is an acronym for ‘Advanced Composite Technology’ – it is a reference to the carbon fibre composite technologies upon which the Wilson Benesch brand was founded and subsequently has become synonymous with. The A.C.T. acronym was used when naming the companies first loudspeaker the A.C.T. One in 1991 and appeared subsequently in the A.C.T. Two, A.C.T. and A.C.T. C60 loudspeakers.

The A.C.T. One Evolution therefore follows a long line of speakers, embodying the heritage of the Wilson Benesch brand and a now classic A.C.T. design. The characteristic sloping, curved A.C.T. top that was revolutionary in the original design remains, but like the C60 before it, the top is now manufactured from carbon fibre. Similar physical proportions have been retained, however the A.C.T. One Evolution has departed entirely from the traditional drive unit topology used in the previous iterations of the design. The new A.C.T. One Evolution incorporates the Troika System which has been taken directly from the flagship Cardinal loudspeaker.

This revolutionary new drive unit topology, combined with the latest State-of-the-Art Wilson Benesch drive technology sets the design apart from the A.C.T. designs which precede it.

When distilled, the constituent parts of the A.C.T. One Evolution are a bold a statement of the expert engineering, manufacturing and craftsmanship that now pertains at Wilson Benesch. Taken as a whole, the A.C.T. One Evolution — with its characteristic foot design, drive technology and alloy baffle — is a pure Geometry Series thoroughbred.


Technology

CARBON FIBRE TOP

The A.C.T. One Evolution is a distinctive Wilson Benesch design drawing direct references to the company’s multi award winning A.C.T. loudspeaker lineage. Its sculptured, curved and sloped top is a direct descendant of the original A.C.T. One loudspeaker. Launched in 1995, the original A.C.T. One was a revolution in loudspeaker design and it’s top was the first example of a sloping design in the industry. The modern equivalent has been manufactured using the same highly advanced carbon composite tooling used to create the loudspeaker cabinet, the A.C.T. One Evolution top is a masterpiece of engineering.

PORT TUBES

The A.C.T. One Evolution features two midrange ported enclosure, with a port directly behind both the upper midrange and lower midrange/bass drive units. In addition, the A.C.T. One Evolution has a large 80mm diameter port terminating directly underneath the speaker. Each port has been tuned optimally through adjustments to both their length and the diameter of the ports, in accordance with the specific characteristics of the Tactic II Drive Units. In general this allows an extension of the frequency response of each drive unit, in particular in the bass register.

A.C.T. MONOCOQUE

Standing at 1.2m (47”) in height, the A.C.T. One Evolution is a striking combination of precision-machined alloy baffle, alloy side panels and the Advanced Composite Technology ‘A.C.T.’ Monocoque. The A.C.T. Monocoque is a geometrically optimised carbon fibre composite structure that exhibits industry leading resonance damping and signal-to-noise characteristics. The inherent stiffness of the A.C.T. Monocoque allows the removal of complex internal bracing commonly used to control cabinet resonance.

SEMISPHERE TWEETER

At the centre of the Troika System is the Hybrid Dome Technology Semisphere Tweeter – a highly engineered solution for high frequency sound reproduction. As the pioneers of carbon fibre composite technology, Wilson Benesch drew upon more than two-decades of knowledge and expertise to create a hybrid diaphragm for the Semisphere consisting of carbon fibre and silk. The hybrid dome is a direct departure from hard dome technologies now used as standard across the industry for wide bandwidth tweeter design. The natural sound produced by the Semisphere dovetails directly into the open sound of the midrange to create a highly integrated system, with stunning soundstaging and detail.

TROIKA

In the midrange, Wilson Benesch introduces technology taken directly from the flagship Cardinal loudspeaker. A two part cabinet construction sees a single 7” upper midrange Tactic II drive unit and Semisphere Tweeter operate in a volume-optimised enclosure, allowing acoustical roll off of the drive unit. Directly below the Semisphere Tweeter in the main enclosure, a 7” lower midrange Tactic II drive unit resides – placing the Semisphere at the heart of the midrange design in a formation known as the Troika System. The reduction in complex crossover elements translates directly into a highly articulate and natural midrange sound and marks a significant advance in the performance of the midrange to Wilson Benesch.

TACTIC II BASS DRIVER

The A.C.T. One Evolution bass frequencies are delivered by a 7” Tactic II Bass Drive Unit. Like the midrange drive units, it features a powerful Neodymium rare earth magnet encased in a motor assembly developed with the Sheffield University to optimise flux across its geometry. This exotic magnet design is combined with a streamline basket and a light stiff Isotactic Polypropylene cone to create a powerful bass drive unit. By installing the Tactic II Bass Drive Unit inside the 26-litre lower enclosure of the A.C.T. One Evolution, maximum dynamics, deep powerful bass frequency response and precision are achieved.

KINEMATIC LOCATION

First introduced in the kinematic bearing design in the Wilson Benesch A.C.T. One Tonearm in 1991, the bearing was designed on the principles of kinematic coupling. The fundamental principle of kinematic coupling is to selectively eliminate each one or all of the six degrees of mechanical freedom that any physical body has. In the A.C.T One Evolution, three 14mm steel threads, tipped with a 6.75mm steel ball, meet with three 6.75mm steel balls, held captive inside the floor protector. This creates a triangulated structure, with a contact point of less than 1mm2 , which provides high-integrity, stable location of the loudspeaker.

Specification

DRIVERS 1 x 25mm ( 1") Wilson Benesch Semisphere tweeter
2 x 170mm ( 7") Wilson Benesch Tactic II mid-range drive units
1 x 170mm ( 7") Wilson Benesch Tactic II bass drive unit
CONSTRUCTION Poly-alloy hybrid construction,
High performance carbon composite A.C.T. monocoque
Lower mid range ported enclosure
Upper mid range ported enclosure
Bass ported enclosure
PERFORMANCE 2.5-way floor standing loudspeaker
Impedance: 6Ω nominal / 4Ω minimal
Sensitivity: 89dB at 1 metre on-axis, 2.83V input
Frequency response: 34Hz - 30KHz +/- 2dB
Minimum amplification power recommendation: 100 W / channel
Crossover frequency: 180Hz / 500Hz / 5kHz
DIMENSIONS Height: 1190mm ( 46.8")
Width: 230mm ( 9.1")
Depth: 400mm ( 15.7")
Volume: 46L
Weight per Channel: 50kg (110 lbs)
FINISHES Black anodised baffle
Satin black spines, foot, division plates
High gloss black top
High gloss satin weave carbon fibre cabinet
Bespoke side cheek options