Church Sound System Case Study: St Francis RC, Belmont

A 1902 Church, Its First Sound System, and a Priest Who Leads by Ear

How we designed a complete audio and livestream system for St Francis of Assisi RC Church, Belmont, a National Trust-listed building of limestone and granite, where acoustic treatment was never an option.

When St Francis of Assisi RC Church in Belmont was blessed in May 1902, nobody imagined it would need a church sound system. It was designed by the Irish architect Ashlin in the Irish Romanesque style, with rounded arches, granite columns, a round tower and limestone walls two and a half feet thick. It was built to carry voices the old way.

In 2010, structural problems forced the church to close. For 14 years the Belmont parish worshipped elsewhere while it raised the money to bring the building back. When the restoration was finally underway, the parish asked us to give the church something it had never had in 122 years: a professional sound system, and a way to share its services with people who couldn’t be in the pews.

The restored nave. Front-of-house speakers sit on the first pair of columns, aimed into the pews.

The challenge: a beautiful room that works against speech

There was no existing church sound system to upgrade. That meant no legacy equipment to rescue, and no old cabling to untangle. But it also meant the room itself was the whole problem.

The nave is roughly 45 by 52 feet under a peak of just over 38 feet. The walls are solid stone, the floor is hard, and the ceiling is timber. Sound bounces around a space like that for a long time. In acoustic terms, it has a very high RT60 (reverberation time). Every word from the altar is followed by its own echo, and the echo buries the next word.

In most rooms, you’d treat that with acoustic panels. In a heritage Catholic church in Trinidad, that is almost never on the table, and rightly so. The building’s beauty is the point. So everything had to be solved by the system design itself.

The parish’s building committee had written a serious specification. It asked for speech intelligibility (STI) to accepted standards, sound levels within OSH limits, and no feedback, even with three sanctuary microphones open and nobody standing at them. It also required that the system be simple enough for one trained person to run, that it be visually unobtrusive, and that it come with full documentation. That’s the kind of RFQ we wish every client wrote.

The solution

We designed the church sound system around a simple idea: an ordinary Mass shouldn’t need a sound technician.

• Loudspeakers: four JBL Control 29AV-1 speakers on the front and rear nave columns, with 110° × 80° rotatable horns aimed at the pews and away from the stone. There are powered monitors for the sanctuary, the sacristy and the choir loft.
• Processing and amplification: a Yamaha MTX3 matrix processor with a DCP4 wall control panel, and two Crown XLi 1500 amplifiers.
• Choir and events: an Allen & Heath CQ-18T digital mixer in the choir loft, with Shure SM58 and SM57 microphones.
• Sanctuary microphones: Shure CVG18 and MX424C gooseneck condenser mics on the altar, ambo and lectern, a Shure BLX wireless handheld, and a dedicated ambience mic for the stream.
• Streaming: two 20× PTZ cameras on 3G-SDI, a joystick camera controller, a Blackmagic ATEM Mini Pro switcher, and a Dell Precision workstation in the loft.
• Power and infrastructure: Furman power sequencers with keyed remote triggers in both racks, Ubiquiti WiFi 6 access points, and EtherCON audio snakes.

The part the parish uses every day is the simplest. For a small Mass, one key is turned. That powers the sacristy rack, the amplifiers and the processor, and the church is ready. For weddings, funerals, concerts and larger celebrations, a second key brings up the choir loft system and the video, which are run from the loft mixer. The system scales with the service instead of demanding an operator every Sunday.

Tuning a stone room

Because we couldn’t change the room, we controlled what we put into it. We set delays on the rear speakers so their sound arrives in step with the front pair, and the back pews hear one voice rather than two. We ran room EQ to tame the stone and timber then set the gain structure carefully from microphone to amplifier and put gates on the microphones so unused mics close. Fewer open microphones means less energy feeding the reverberation, and far more headroom before feedback.

Why the sound had to be right

There was one more reason this job mattered. The parish priest, Fr Mikkel Trestrail, is blind.

For most congregations, the church sound system is how people hear the priest. At St Francis, it is also how the priest follows his church. He relies on what he hears to track readers, the choir and the flow of the liturgy. That made the sanctuary monitoring, clean levels and a noise-free system essential, not optional. It’s also why a simple key switch suits this church better than a touchscreen.

The result

On Monday, 23 September 2024, Archbishop Charles Jason Gordon presided at the Mass of Dedication before a packed church. According to the Catholic News, he told the congregation the restored building “takes the mind and heart up to God.” The new system carried that Mass, and everything went splendidly.

Our installation stretched over a long period, because we were working alongside several other trades during a live restoration. Our team worked around scaffolding, fresh finishes and roof work. In keeping with our practice, the parish received as-built drawings, labelled cabling, manuals and all system passwords.

The bigger problem in Caribbean churches

St Francis is the exception. Most churches here end up with poor sound for the same few reasons: donated equipment, volunteer installs, lowest-price bids and no acoustic design at all. People buy “a speaker” without thinking about frequency response or coverage angles. In a reverberant stone church, that usually means sound that is loud but not clear. Parishes then spend years adding more equipment to fix a design problem.

There are also very few AVIXA CTS-certified professionals in the region. That shows up in unlabelled cables, missing drawings and systems nobody can maintain.

What to ask before you hire an integrator

Read more about the project here