The Tokyo Roppongi Hills mega-complex is a creative hub that incorporates office space, apartments, shops, restaurants, cafés, movie theatres, a museum, a hotel, a major TV studio, an outdoor amphitheatre and a few parks. Residents believe it will not only be a model for Japan, but the whole of Asia.
Constructed by building tycoon Minoru Mori, the complex also contains the Roppongi Hills Arena – an entertainment venue that has a huge removable roof. From live entertainment to red-carpet affairs, it will host many types of show that will now include open-air events. In February 2018, the Arena completed a major refurbishment to enable it to host a broader range of entertainment, but faced the imperative to decrease neighbourhood noise pollution. An improved sound system and monitoring capability were required.
After auditioning many loudspeaker brands, Martin Audio’s CDD series was selected. This uses patented Coaxial Differential Dispersion driver technology and has a unique dispersion pattern compared with legacy loudspeakers. The 15-inch CDD15-WR, in weatherised format, was specified. The venue requisitioned 12 cabinets which have been installed on the round shaped truss at the top of the facility, while a further eight CDD15-WR speakers have been installed on the wall.
The loudspeakers were tuned to maximise their potential. Signal transport from the amplifiers is via a Dante digital network which delivers a clear, pristine sound with no loss, thanks to the digital signal path.
Mr Sato, who specified the technology, stated that the upgrade had been without compromise: ‘I had been wanting to provide premium sound to the audience for a long time,’ he says. The goal was obvious but there were many considerations, such as it being an open-air venue and the fact that we needed to avoid noise pollution for the sake of our neighbours. In addition to that, the location of the loudspeakers in the past had not been of sufficient quality to cover every seat in the venue. ‘The dispersion of CDD Series is unprecedented. Not only is the sound quality nice, but the wide dispersion brought coverage to areas that had previously been dead zones.’
The loudspeaker system is driven by five Powersoft X4 DSP+D amplifier, tuned to the Martin Audio loudspeakers with a Symetrix Radius 12x8 processor feeding signals to the amps via Dante. Using Powersoft’s specialised control software, Armonía, alongside the amplifiers, all of the output signals can be optimised and the limiters adopted properly. A unique feature of Armonía is Operator View, which can help engineers during their daily operation of the audio system by enabling remote control from a smart phone, tablet or laptop, and using custom interfaces to control the gain value of any outputs. This tool also helps engineers to monitor the condition of the system all the time.
‘The latest installation has served as a solution to many compromises that were made here in the past,’ says Sato. ‘The goal of premium audience sound is obvious, but there was many issues; particularly arising from the fact that the venue is open air and so at risk of causing noise pollution to the neighbours. In addition to that, the old loudspeaker locations were not good enough to cover every seat in the venue.
‘The new system has changed this situation. As well as combatting dead zones with the new speaker placement, we are very happy with the performance of the Powersoft X4 amplifiers. The output capability of the amps allow us to maximise the powerful, clear sound from the PA system, and being able to tune it perfectly using the Armonía software was invaluable. We now have control of the system’s output in all outdoor areas, adopting individual EQs and delay settings to create the best possible sound everywhere in the venue.’
The loudspeaker installation was fulfilled by Martin Audio Japan, who will continue to support this creative city.
