KS28 flies at the Tokyo Dome for Kyosuke Himuro’s final concert
JAPAN: Approximately 50,000 fans sold out the Tokyo Dome recently for the final concert performed by Japanese pop star Kyosuke Himuro at the conclusion of his Kyosuke Himuro Last Gigs tour. System engineer Mitsunari ‘Saiji’ Gengoromaru, working in collaboration with the artist’s front of house engineer Kevin Elson and Akitsugu Kemmotsu from Measurement Works Co Ltd, designed the system that comprised L-Acoustics K1 loudspeakers as well as the manufacturer’s new KS28 subwoofers. The L-Acoustics system had been introduced initially to Mr Kemmotsu by the managing director of L-Acoustics’ Japanese distributor Bestec Audio, Takayuki Ozaki. Contracted to supply the audio solution on the tour were rental companies Hibino Sound and Tokyo Sanko.
While fans of the singer-songwriter were reportedly treated to an ‘emotional experience’ during his last ever live performance at the Tokyo Dome, the sound engineers were tasked with tackling the unique acoustical challenges that the venue presents. Due to its air-supported roof, there are strict weight-restrictions in place when it comes to hanging equipment from the ceiling of the Tokyo Dome. Mr Gengoromaru specified the L-Acoustics solution, which had not previously been deployed at the venue, due to his experience in working as a systems engineer on large arena and stadium shows that had taught him that controlling the bandwidth of subwoofers could be a particular problem. Utilising Soundvision simulation software, he predicted that the K2 and KS28 system would achieve even coverage.
The system consisted of left and right hangs of 20 K1 units and four K2. Also flown was an array of 12 KS28, while 16 SB28 units were ground-stacked. Providing coverage at the side of the Dome were 16 K1 and eight K2 flown per side, while side-fills were in the form of six Kara arrays, three per side. L-Acoustics’ LA12X and LA8 amplified controllers drove the setup.
‘Flying KS28 and K1 arrays next to each other produced a very powerful, evenly-phased system. Despite the audience being 50,000-strong, it delivered very clear low frequencies throughout, which had never been experienced in the Tokyo Dome before,’ said Mr Ozaki. ‘The whole stadium experienced a true “rock sound”, which helped to ensure the audience was “as one” with the artist throughout the show.’
In spite of the ceiling limitations, the crew were able to hang the KS28s due to their 79kg weight. When paired with the LA12X amplifier, the KS28s produced 3dB SPL more that the SB28, meaning that there was reportedly no need for delays and that members of the audience up to 160m away still experienced the low frequencies.
‘Without the many other advantages of L-Acoustics systems, including light weight, ease of rigging, audio quality and accurate Soundvision simulation, the show would have had to use a conventional system, which would have delivered a noticeably poorer experience for the audience,’ added Mr Ozaki. ‘The KS28’s mid and low frequency reproduction has been further improved by the new switched-mode power supply (SMPS) with DSP-controlled Power Factor Correction (PFC) of the LA12X, which can maintain the maximum sound pressure level over a longer time, even at 100V.’
‘I really appreciated the excellent system,’ concluded Mr Kemmotsu. ‘I had never experienced such an even pattern and sound pressure throughout the entire bandwidth in this venue.’