Most of the speaker systems available then were derived from American cinema systems, like Westrex, RCA, JBL, Altec, and EV. They were used in the States by bands, purely because they had the high output and efficiency needed for large venues. What they lacked was any form of sound fidelity, simply because their specifications were limited to those applying to low-fidelity optical cinema sound tracks.

The Black Box system was introduced in the 1970s with the design parameters of a studio monitor - a substantially flat system response throughout the audio range 40Hz to 16 kHz. It meant the final system was twice the size of its competitors - and considerably more expensive. It comprised a 2 x 15" bass bin with an 8 square foot mouth area with a 7 foot folded horn and ported back chamber. Every permutation of bass drivers was tried from 12 to 24" cones, but listening tests showed that 2 x 15" with 4" voice coils proved to be the most efficient pistons for clean bass. The top end comprised front loaded horns, 2 x 12" for low mid, and again every make and size of compression driver was tried, and although most of Court's competitors were using a 2" driver, listening tests showed that 2 x 1" drivers offered the widest frequency range, higher power handling and least distortion. Finally rather than the conventional exponential horns used by most manufacturers, Black Box used rapid flare rate horns for minimum throat distortion. The low and hi mid horns were mounted laterally so Black Box could be used as a line array. Up until then, the only line array speakers available were columns designed for speech and conference use.

Court Acoustics founder with their first "Hi-fi" PA in 1972-3

The essential difference between this system and its competitors, no equalisation was needed, because its drivers and horn flares were tailored to give a + 3dB frequency response, and it didn't need time delay because all the drivers in the high bin were physically time aligned..

As a consequence of its high fidelity, Black Box was not only used bv major hire companies and artists all over the world, but it was also used for the London Symphony Orchestra classical concerts, and by Philips to launch the new Compact Disc system by comparing a recording and a live orchestra through Black Box. Black Box was also used by Pink Floyd, to augment mainly the thunderous bass needed on their "Brick Wall" concerts and films

In the eighties Pro Sound spread into the club industry, and because records were in direct competition to live music, and because of the high product cost, Court had turned down initial offers to supply the club industry. According to the lighting guru Tony Gottelier in his Disco International Magazine review:

"Court had already turned down approaches from Annabelles in London, and Stringfellows in Manchester, so we naturally asked them to demonstrate Black Box at London's Camden Palace which was to be the country's, most sophisticated night spot. We also reminded Court that all their competitors had demonstrated their speaker systems over the last three weeks, so Court arranged a demo by borrowing a Black Box rig from Roger Lindsey at Europa Concert Hire."

Gottelier added. "Their demonstration at the Camden Palace just blew the competition away - literally - and Court was given the contract on the spot."

BLACKBOX II is made in Britain and all its components are made within Europe.