A new Norwegian hard rock festival, the debut Trondheim Rocks was headlined by Iron Maiden and Volbeat, with an Alcons Audio LR28 PA system addressing the 19,000 fans assembled for two days at the Dahls Arena.

With 16 bands on the bill, Iron Maiden closed the event with their Legacy Of The Beast tour. Sound was supplied by Trondheim Lyd, well versed in festivals and high-profile international concerts. Its large Alcons Audio inventory was ideal for an event where the sound needed to be loud within the arena, but very quiet outside it.

The event featured two stages, a large main stage and a secondary, smaller one to the left, with an audience arena around 109m deep. The main stage system comprised main hangs of 20 Alcons LR28 larger format line array modules each, with 32 BC543 very high output cardioid subwoofers and a total of 39 LR18 compact mid-sized line array modules for inner, outer and side fills. Six VR12 mid-sized versatile monitors were used for front fill (with an additional four RR12 point source array modules for vocal front fill for Iron Maiden only). Pairs of VR8 compact versatile monitors and BF151 compact subwoofers provided nearfills for the FOH mix position.

The secondary stage featured main hangs of eight LR28 each, 12 BC543 subs and six LR18 for frontfill. The systems used a total of 69 Sentinel10 and one Sentinel3 amplified loudspeaker controllers.

Trondheim Lyd has previously used its LR28 system on large-scale, high-volume events. Having seen how well it performed, promoter Trondheim Concerts had the confidence to specify no delay towers at Trondheim Rocks.

‘The promoters knew it is a system with excellent sound quality and they have experienced its exceptional power and throw, so they were sure that delays were unnecessary at Trondheim Rocks,’ says Production Manager, Espen Hammer. ‘At the same time, we wanted the back of the arena to be quieter, but to maintain the same high sound quality and intelligibility. A festival is also a social happening, where people want to talk together, so it was good to have some areas where the audience could sit down with a beer and chat, but still clearly hear everything that was happening on both stages.’

The absence of delays meant larger main hangs, which added potential issues of spill (the closest residential property was just 20m from the main stage) and wind interference. However, the directivity and all-natural cylindrical wavefront of Alcons pro-ribbon technology meant that neither caused any problems.

‘We had no problems in complying with the FOH dB limit of 100dBA Leq 15min,’ says Trondheim Lyd audio tech, Arnstein Fossvik. ‘On both stages we had horizontal arrays of subwoofers and, with the BC543 being a self-contained cardioid sub, there was minimal leakage outside the audience area. Thomas Denstad of dB Control Norway did measurements in and outside the festival area and expected it to heavily exceed the strict city dBA- and dBC Leq30 limits. In fact it only exceeded them by a few dBs and there were no complaints at all from residents.

‘On both evenings, there was quite a strong breeze, but the pro-ribbon drivers really pushed the high frequencies through it.’

This was also noted by Paul Higgins, system tech for Volbeat FOH engineer Mads Mikkelsen: ‘Both Mads and I were thoroughly impressed by the pro-ribbon drivers performance in a crosswind, as well as the enclosure flat response in both magnitude and phase. I thoroughly enjoyed working with the product, and look forward to using it again in the future.’

‘We had the thumbs up from various band engineers and great feedback from the promoters,’ Espen reports. ‘One thing we really noticed was that, in the quiet area at the back at the venue, the fact that people could clearly hear the artists, just at a lower level, stimulated their interest and many were moving forward to check them out. These members of the audience discovered bands that they never would have seen if it had not been for the Alcons system.

‘It was also really nice for me to use a system that weighs less than other PAs we have used in the past. It meant we had more capacity in the roof for lighting, video and sets, which was very important at this festival. Being such a high-profile act, Iron Maiden understandably wanted their production to be as similar as possible to their indoor shows, so we were able to give them a full production, but still within the limits of the stage’s load capacity.

‘Another advantage was that it is so easy to set up. In Norway labour is expensive, so having a system that does not need lots of crew to set up is very good. And, when I put an Ease drawing in the technical specs, it is good to know that the system will behave exactly as expected.’

‘It is quick to set up, take down and fast to program and optimise, while its audio performance is of course superior to any ‘conventional’ system,’ adds Arnstein.

‘I'm very proud of the Alcons Audio and Trondheim Lyd teams for reaching new milestones for both companies at Trondheim Rocks,’ concludes Alcons Audio co-founder Tom Back. ‘Hard rock headliners like Volbeat and Iron Maiden both using Alcons pro-ribbon transducer technology – who would have thought it? It’s proof that passion and persistence makes anything possible, and we have hardly begun…’