British University Vietnam (BUV) – Learning Theatre

Fohhn 7.1 Surround Sound System with Beam Steering Technology

British University Vietnam (BUV) opened its new campus in Hanoi’s Ecopark township with a mission to deliver high-quality UK education in Vietnam. To match this vision, BUV invested in state-of-the-art AV technologies across lecture theatres, classrooms, and shared learning spaces.

The Crown Jewel: Learning Theatre 2

Learning Theatre 2 is an auditorium with a 264-seat tiered arrangement and a striking multi-hued blue façade. The theatre delivers high-impact experiences for lectures, performances, and presentations with a 7.1 high-definition surround sound system.

The FOH live system includes two Fohhn DLi 230 Digital Steerable Line Array Speakers and four Fohhn AT-31 15" Subwoofers. The 7.1 Playback system uses the same subwoofers, six Fohhn AT-40 500W high-performance 2-way passive speakers at the front, and ten Fohhn AT-10 200W high-performance speakers at the rear and side walls. All speakers are powered by Fohhn DSP amplifiers and processed by a Crestron HD-XSP surround sound processor.

Fohhn's beam steering technology provides precise sound coverage despite the theatre's unique geometry. The speakers, placed at the back of the stage, steer sound above the presenter and down toward the audience, maintaining clarity without feedback. Fohhn software enabled precise Sound Pressure Level (SPL) tuning across the seating tiers.

The Fohhn DLi 230 Digital Steerable Line Array Speakers were also installed unusually at the back wall of the stage. The speakers though placed at the back of the wall, have the audio steered above the head of anyone presenting on stage. The sound is being steered over the presenter's head and then down towards the audience. It gives the presenter the impression that the speakers are overhead or on top of him which is the norm for FOH design. As the distance between the speakers and the presenter is negligible, there is no sound delay and it gives the audience the impression that sound is coming "through" the presenter or speaking directly to them due to the sound being steered towards the audience directly. For the presenter it is like having an indirect overhead monitor.

David and his team were also present personally to assist the system integrator to calibrate, tune and commission the sound system at the Lecture theatre.

Nguyen Truong Giang of Hoang Minh Intech., JSC highlights, "This is likely the first project in Vietnam to use beam steering technology. Though it was a challenge to communicate with someone not based in Vietnam, with Skype, phone calls and personal visits we managed to get the system running at optimum and to the satisfaction of the University."

The challenge of feedback was resolved with the speakers' acoustic centre tuned precisely. The team demonstrated and convinced those involved by pointing a working microphone directly at the front of the speaker, with no feedback.

Space constraint was the reason the speakers are not in a typical FOH design. As for the sound coverage in a tiered seating arrangement, the latest Fohhn Audio Software allows one to check on the SPL and coverage in side elevation and to see the SPL from the first row to the last row based on the distance measured on site. The software also allows the engineer to draw an elevated listening plane on the software during programming to check how is the SPL and coverage. The two beams technology allowed us to adjust the SPL to have a± 3 dB between the first and last row, which is almost indiscernible to the human ear.

Though it is easier said than done, it will take years of experience and practice to understand and configure the sound that is of high intelligibility and yet gives High Fidelity ambience for musical productions. The Fohhn Linea Focus speakers also allow the engineer to turn off the side lopes in a badly reverberating room or a room with very bad acoustics to reduce all possible reflections from the environment or turn it on for ambience enhancement to give a little bit of reverb to make the room more lively. These were some of the measures we took to meet the challenge of the space."

The Fohhn surround sound system in the Learning Theatre was supplied, supported, and commissioned by Control Logic Systems (CLS), an independent AV distributor now part of Ideal Systems SEA. CLS worked closely with the on-site team to calibrate and fine-tune the Fohhn DLi 230 Digital Steerable Line Array Speakers and DSP amplifiers, ensuring optimal performance of the 7.1 surround system. With this successful deployment, Ideal Systems SEA continues the legacy of CLS in delivering world-class AV solutions across Southeast Asia.

Source: This case study is based on a feature originally published in Systems Integration Asia, Vol. 18 Issue 2 – Dec 2018 / Jan 2019.