The heritage site and museum commemorating the achievements of British World War II codebreaking at Bletchley Park has furthered its visitor experience with the opening of the Fellowship Auditorium – the most recent addition to the Milton Keynes site. The auditorium features 250 seats and is part of a broader development that includes the Diesel House reception area and the Radley Room social space, as well as a new Learning Centre.
In designing an audio system for he auditorium, its 180° radial seating arrangement presented acoustic challenges that required the expert attention of L-Acoustics Certified Provider Adlib, having won the tender for the space.
‘The unique configuration of the space, with seats arranged in a 180° arc around the stage, meant that crystal-clear speech reproduction was essential,’ explains Adlib System Designer, Tim Robinson. ‘As primarily a lecture venue, every seat needed perfect intelligibility.’
L-Acoustics Soundvision software played a crucial role in the system design process, enabling Adlib to model and verify proposed solutions while providing visualisation tools that helped other trades understand the final implementation.
‘Soundvision was invaluable not just for technical modelling, but also for helping everyone involved visualise the end result,’ Robinson confirms. ‘Being able to show realistic 3D renders to the client and other contractors made a huge difference in communicating our vision for the space and coordinating with other trades who are not used to dealing with professional loudspeaker systems.’
The project’s primary objective was to ensure sound would come from directly in front of every listener, rather than being biased towards one side or the other. This promted use of a monaural system with a single source.
The installation comprises six horizontally arrayed L-Acoustics A10i Wide constant curvature enclosures providing the requisite 180° of coverage, complemented by two KS21i compact subwoofers. These are powered by LA4X and LA2Xi amplified controllers, providing precise control and optimal performance across the entire frequency range. The horizontal array configuration, facilitated by A10i-Lift rigging elements and various linking plates, ensures even coverage throughout the space.
‘We knew a fixed-curvature line source would be perfect for this application,’ says Robinson. ‘The coverage pattern of the A10i Wide was exactly what we needed, and its compact size meant we could achieve excellent results without overwhelming the space. The adjustable HF pattern control was particularly useful in managing reflections from the ceiling and the optional front screens were specified to minimise the system’s visual impact.’
While speech intelligibility was the primary focus of the installation, it has surpassed expectations in both performance and versatility. Its quality has also led internal event managers to plan a conference featuring a live musical performance, confident in the PA system’s capabilities.
