The El Tabernacle church in Walkerville, South Africa, has suffered from acoustic issues since its construction, making it difficult for worship leaders to be heard above an enthusiastic congregation. Faced with considerable challenges, church elder Gustav Adams approached Richard Smith of local technical production specialist Sound Harmonics for advice…

‘As part of a complete technical revamp of the building, I was asked to come up with an overall plan to achieve high quality, clear and powerful sound,’ he explains. ‘When sizing up a project like this, I like to analyse both the client’s need as well as the hurdles posed by the space itself in a step by step process that allows me to hone in on the best product.’

At El Tabernacle, the room size of over 50m immediately pointed Smith and his team towards a line array. Further analysis of the average congregation size, the type of service, the comportment of the congregation and the type of music being used, as well as the budget was conducted.

‘We realised that in addition to a room requiring a long throw, the church has a very loud band and a surprisingly loud, exceptionally responsive and vocal congregation during services,’ Smith says. ‘The church team are all very musical and pretty clear about what they want to hear. The system needed excellent intelligibility, but also enough SPL to overcome and accompany the congregation’s enthusiasm. In addition, the room was acoustically untreated and the expectations we extremely high, so we had to make a careful choice.’

He proposed L-Acoustics KARAi and SB18i for their compact footprint and low weight, coupled with enough SPL to cover the entire space – and, most importantly, be heard by all of the congregation.

Adding to the challenge, the stage position is similar to being located beneath a balcony with a closed front. There is a low roof above the stage, with a ‘bulkhead’ across the front, which is part concrete slab and part hollow wooden façade. ‘The closest ceiling beam that we could have used to fly the main system is around eight metres in front of the stage, so we had to make custom metal beams to hold the KARAi and sub arrays, in order to get them as close to the bulkhead as possible. Even in this position, the main arrays are around two metres in front of the stage lip, so we added ARCS Wide as fills behind them,’ Smith says.

The design uses a main system of nine KARAi and four SB18i per side, with the subs being flown in cardioid configuration. Fills comprise a centre cluster of two ARCS Wide in a horizontal configuration, plus another ARCS Wide per side as front fill, augmented by a 12XTi out fill per side. A comprehensive monitoring setup includes four 12XTi and two 8XTi for the pastor, further pairs of 12XTi for the choir and side fill, with two more 8XTi for the church elders. The entire system is powered by LA4, LA4x and LA8 amplified controllers.

Modelling everything in L-Acoustics SoundVision 3D acoustical simulation software was crucial to the project. ‘It is such a reliable and accurate tool that I am always confident in showing a client the result I am after, because I know that’s exactly what I will achieve. This project was a great example of that, the SoundVision plot precisely matching the coverage and SPLs that we achieved,’ Smith assures.

Founding Apostle Edgar Hill Roscoe and the church elders have pronounced themselves very happy with the system, with its size and the aesthetics coming in for as much praise as the seamless coverage and sound quality. ‘The system looks good and the client is ecstatic that we could supply it in white. In many ways the church is quite conservative and the ability to blend the speakers into the background was very important.’

Since the El Tabernacle tech team is run by volunteers, Sound Harmonics also spent time making sure the system was calibrated to the sound they wanted, and then training the staff to maintain it, week after week. ‘The Church was very clear about they wanted to hear and KARAi delivers it in bucket loads,’ Smith concludes. ‘It’s clear when there is preaching and it gives them all the feeling they need when the praise and worship music is as loud as any rock ’n roll concert.’

The church has been so satisfied with the system that they will soon add 5XTs to create a low level distributed close field monitor system for the choir and band, further enhancing the experience of services for the performers.

More: www.l-acoustics.com