Martin Audio shows sensitivity to sound in London’s Hyde Park15 August 2013
When Luciano Pavarotti used to sing here, with a huge PA, none of the neighbours complained. But if a rock or hip-hop act produced the same or even lower SPLs from the temporary stages erected each summer, tongues wagged in regulatory ears.
It was known in PSNEurope circles as ‘Speakers Corner’, in honour of the bastion of free speech associated with ad hoc gatherings of tub-thumpers in another part of the park; now it seems – thanks to a very specific technological breakthrough – the critics of Hyde Park’s musical promotions may have to pipe down themselves.
The problem was always the same: if you turn it down to assuage public concern, you run the risk of disappointing paying customers. Despite the best efforts of professionals including Vanguardia Consulting to mediate sensibly, the ideal compromise always proved elusive and, this summer, wholesale changes to the infrastructure of Hyde Park’s concerts have been introduced as the quest continues.
Rebadged as ‘Barclays British Summertime Hyde Park’, the gigs have a new promoter, AEG/Loudsound; a new rental supplier in Capital Sound; and a new PA system for the main stage – which is orientated at a different angle to before and now presented as the ‘Great Oak Stage’, featuring more fake plastic trees than a Radiohead album. That system is Martin Audio’s Multicellular Loudspeaker Array, aided and abetted by an Optocore fibre-optic redundant loop.
About 180 boxes were deployed: 17 MLA enclosures per side, including one MLD downfill; 13 MLA outfills per side, also including one MLD; 16 W8LM front fills; 32 MLX subs in cardioid broadside array formation; and 10 delay towers at 90m and 160m repeating the MLA/MLD configuration albeit with just eight MLAs plus – for the big acts – two more delay points at 210m using MLA Compact enclosures. Optocore’s X6R-FX converters – with Ethernet – were used to secure the kilometre-plus delay ring.
At FOH, aside from a couple of digital consoles from DiGiCo and Avid, the most striking configuration is a huge empty space facing the stage – awaiting the arrival of The Rolling Stones’ monolithic Yamaha PM5000 and its twiddle-ready faders.
Such is the importance of getting this right, a dry run was staged where most of the conditions within and around Hyde Park could be re-created – just as negotiations between all the interested parties were reaching a peak. “We built the front end of the system in the grounds of Hatfield House in January,” recounts Ian Colville, Technical Manager at Capital Sound, “where there’s room to measure the equivalent off-site SPLs to here, at the correct positions. Vanguardia took very detailed measurements, not only at the noise-sensitive offsite locations but within the audience footprint as well. We programmed various long-throw presets, and the results came out very favourably.”
@page_break@ Indeed Capital was able to achieve a 6dB(A) increase within the perimeter without disturbing the 75dB(A) average limit set for all the main trigger points off site. “The limits under the current Hyde Park licence were set last year, and will continue for several years,” says Olly Creedy, Senior Acoustic Engineer at Vanguardia. “So the real task is to get the on-site levels up while staying within – or even some way below – those parameters. Re-positioning the stage has certainly helped with that – essentially, away from Park Lane – along with the new system.”
In order to predict the SPL over distance, Martin Audio exported the 3D balloon data of the arrays, using their Display 2.1 optimisation software. Vanguardia were then able to feed that in to their long range propagation model, without the need for any third party simulation software – which could have compromised accuracy.
But we’ve done this a few times now and it’s the same experience right across the MLA user network, from here to Japan – other rental companies tell us that people are asking for MLA, not just for the noise control issues but because you can do things like a small festival without any delays at all, and that’s a huge saving.
“It’s such a different system. You look at it casually and think ‘line array’ but it’s nothing like that: the DSP inside it is manipulating phase, amplitude… all sorts of stuff. When the audio arrives where people are standing, or sitting, it really has all come together.”
The gods could not have dreamed up a more testing line-up for the new solution: headliners on different nights included Bon Jovi, not known for their acoustic restraint, and The Rolling Stones, not known for avoiding controversy through several generations of self-appointed guardians of social decorum.
If there are any net curtains left to twitch in Mayfair, Mick Jagger may just have enough residual testosterone to twitch them a little bit more as the band defibrillates the very last tendrils of the 1960s. However, all reports to date suggest that the sound ‘bubble’ worked: no serious complaints, no letters to The Times and no dawn raids on Capital Sound’s premises by the Vice Squad. Maybe next year the number of concerts will be allowed to go back up to thirteen.