Capital Sound Supplies Martin Audio MLA for SW4 Festival

	SW4 Festival. Photo: Chris Taylor Photography

Lock N Load Events' annual South West Four (SW4) Bank Holiday Weekend festival on Clapham Common this year reached new sound thresholds set by Lambeth Council as Capital Sound again set to work with their award-winning Martin Audio MLA multi-cellular system.

Working for the third consecutive year with promoter Andrew Mattle, the responsibility for MLA has slowly extended from main stage, where drum and bass kings Rudimental and veteran techno specialists Chemical Brothers headlined, into the three support tents.

Capital account manager Martin Connolly confirmed that while the MLA family was again featured in all areas, the MLX subs were deployed in two different formats, namely a broadside cardioid array on the main stage while stages two and three had cardioid stacks under the hangs. On stage four, four WS218X subs were set each side on stage in an end-fire configuration, all of which saved on valuable space between pit and barrier, normally occupied by the sub arrays.

But the biggest change on what has traditionally been a noise sensitive site was that late in the day, Lambeth Council issued guidance of control documentation confirming the new sound thresholds. However, they set the limitations in C-weighted values (rather than the more customary A-weighted figures recognized by sound engineers.)

The festival had announced these sound level increases as "breaking news" late in the day on their official website, stating: "We would like to take this opportunity to say a truly massive, heartfelt thanks to each and every single one of you who has personally supported us over the last three years (and in particular this year) with our fight to get sound levels increased on Clapham Common ... We look forward to bringing you the biggest, most explosive, and loudest South West Four ever."

Martin Connolly welcomed the formal documentation that legitimized the sound levels but was surprised by the decision to impose this in C-weighted values. "These measurements include much more of the low-frequency range of sounds than the A and B scales. However, C-weighted is very difficult for live engineers to interpret."

"We were fortunate, however, that by using the new Martin Audio Display software, with FIR filtering to improve LF control, we could achieve really good levels and work within the offsite limits." Capital was also fortunate in having the experienced system tech Toby Donovan on hand to carry this out.

For the Chemical Brothers' experienced sound engineer Shan Hira, using an analog desk and outboard setup, this correlated to a maximum of 102dB(A) at the mixer -- with all other stages closing at 9pm. "However, I was surprised we managed to peak at the same level for Rudimental the previous night, as all the other tents were still functioning up to 10:00 - 10:30pm," noted Connolly.

While main stage and stage two both featured an MLA rig, stages three and four were equipped with MLA Compact. The subwoofers were as described above, with one notable exception. Martin Audio R&D director Jason Baird suggested an asymmetrical dispersion pattern on the main stage sub array to make the dispersion narrower on the noise sensitive side. Again, Donovan took care of the programming, helping to monitor offsite sound spillage from a cabin behind front-of-house.

Bank Holiday Monday saw a more sedate affair, with Madness curating the House of Common festival featuring Toots & The Maytals, Lee "Scratch" Perry, and others who have influenced Two Tone Records.

Summing up, Connolly said, "This was a landmark for Clapham Common and I know the promoters were happy with the sound levels achieved. Historically, Clapham Common has only been 96-98dB(A) -- so by raising this to the equivalent of 102dB(A) while still hitting the offsite limits with MLA it was a major breakthrough."