Grainger Communication’s CBT70J’s appear to be floating in mid-air above the sanctuary
The congregation of Church of Our Lady Queen of Peace in Kilwee, in the suburbs of Belfast, has been presented with something of a phenomenon. Through the unusual omega-shaped sculpture — suspended from the ultra-high vaulted ceiling and hovering over the sanctuary — four JBL CBT70J column loudspeaker arrays now appear to float, as if defying the laws of gravity.
Not the miracle they were perhaps hoping for since these are hung on near imperceptible steel wire pairs — an ingenious solution conceived by Martin Grainger, of Co. Tyrone based Grainger Communication Ltd to give extra design swagger to a modern church which was only built at the turn of the millennium.
The acoustician has been involved with the unusual conical-shaped church, with its extraordinarily high ceiling for many years and is entirely familiar with its acoustic quirks and reverberant interior.
“Although we didn’t carry out the original [sound system] installation we have undertaken a lot of work at the church since and we have watched the incremental changes that have taken place,” says Grainger.
The incumbent priest, Fr. Colm McBride, was far from happy with the sound quality, and the installers felt that a lot of his misgivings would disappear with the installation of JBL’s Constant Beamwidth column arrays, correctly aligned.
These passive speakers use JBL's breakthrough Constant Beamwidth technology to produce a column speaker with incredibly balanced projection across a large area — making it perfect for large, challenging rooms such as this. Using an array of four 5"" LF drivers and 16 x 1"" HF drivers, the result is consistent, natural sound coverage — both horizontally and vertically.
To optimise the sound for the 300 or so congregation, the acoustician noted that downlighters were recessed into the horseshoe-shape feature, with the seating arranged in a semi-circle to contour the shape. Instead of the existing speakers, mounted on the sculpture, he proposed that four of the JBL loudspeakers be suspended from this horseshoe, correctly angled to achieve even dispersion (and at the same time avoiding the downlighting).
“I told Fr. McBride he was going to have to trust me on this,” said Martin Grainger, “and if he was not happy we would take them back out again. We suspended the speakers 1.5-2.0 metres from the horseshoe on two very fine steel wires using them as the conductors rather than conventional cable.”
After conducting measurements, Grainger Communication fabricated their own brackets to ensure they could achieve 100% accuracy with the tilt angle towards the congregation. The result gives the impression that these speakers are defying the laws of gravity and floating in mid-air.
Taking inputs from AKG GN155 and GN30 gooseneck mics, processed with the pre-existing Soundweb Lite 3088 DSP, the result is far beyond expectations.
Summing up, Martin Grainger said, “We have received many comments [from members of the congregation] that this is the best sound system they have ever had. Fr. McBride was initially sceptical because this solution hadn't been attempted before — but he’s delighted. After all, why not dispense with cables in favour of two steel wires and at the same time minimise the mess!”