The Silent Saboteur: Why Acoustics Deserve Centre Stage in AV Design Projects

As audio visual design experts with many years of experience in the field, we've witnessed countless projects where cutting-edge AV systems — think high-definition displays, seamless video conferencing, and immersive audio setups — fall flat due to one critical oversight: acoustics. It's a silent saboteur in AV design projects, turning potential triumphs into frustrating failures. In this blog, we'll explore why room acoustics in AV are so often ignored, the real-world impacts on user experience, security and compliance, and how integrating acoustic design early into a project can transform outcomes. 

Drawing from our experience at CornerStone, where we champion a holistic approach, we’ll share practical insights for architects, AV consultants, building managers, and risk leads in sectors like banking and financial services, professional services, data centres, construction, the public sector, and critical infrastructure. 

The Root of the Problem 

The root of the problem lies in systemic issues within project workflows. Siloed procurement is a major culprit: AV designers are brought in after architectural decisions are locked in, leaving little room to address acoustics. Late engagement means acoustics is treated as an afterthought, retrofitted rather than designed in. Weak briefs exacerbate this – clients often specify AV tech without acoustic performance criteria, assuming digital wizardry will fix everything. And then there's overreliance on Digital Signal Processing (DSP). While DSP can enhance audio, it's no substitute for proper acoustic treatment; it can't magically overcome the inherent flaws in a space like excessive reverberation or noise bleed. 

Consider speech intelligibility in meeting rooms – a foundation of effective communication. In hybrid working environments, poor acoustics leads to muffled voices, echoes and fatigue during video calls. Building acoustics for video conferencing must account for this, yet many spaces with costly AV installations still suffer from subpar sound. Why? Because without acoustic design for conference rooms, even the best microphones and speakers struggle. 

Clear Benchmarks 

Tangible benchmarks highlight the gap. Aim for a reverberation time (RT60) of under 0.6 seconds in small meeting rooms for clarity. Speech Transmission Index (STI) should exceed 0.75 for excellent intelligibility – anything below 0.60 spells trouble, especially in voice alarm systems where voice alarm intelligibility STI is a life-safety issue. In transport hubs or public sector buildings with PA/VA systems, low STI can mean critical announcements are misunderstood during emergencies, risking lives. 

Speech privacy adds another layer of urgency, particularly as an information risk in sensitive sectors. In banking and finance or professional service environments, for meeting rooms, where confidential meetings are commonplace, sound masking and speech privacy are essential to prevent eavesdropping. Open-plan office acoustics increase this; without proper absorption and barriers, conversations bleed across desks, compromising data security in areas of highly sensitive communication. Healthcare privacy can demand even stricter measures – think of patient consultation rooms, where poor acoustics could expose sensitive information. Noise criteria like Noise Rating (NR)/Noise Criterion (NC) ratings provide benchmarks to ensure privacy without over-isolating spaces. 

Sector-specific examples underscore these challenges. In classrooms within the public sector, inadequate acoustics hinder learning; studies show students in reverberant rooms absorb 25% less information. Construction projects often overlook acoustic treatment, leading to rework costs that negatively impact budgets. For data centres, where video conferencing bridges global teams, ignoring acoustics means lost productivity amid echo-plagued calls. Meanwhile, in critical infrastructure, like transport, PA/VA systems must meet stringent standards – yet many fail due to unaddressed room resonances. 

The Good News 

Integrating acoustics and AV design from the outset flips the script. Start with a meeting room acoustics checklist: assess room volume, surface materials, and usage early. Collaborate across disciplines – architects define shapes and finishes, AV consultants model sound propagation, and facilities teams set performance specs. This holistic approach, which CornerStone advocates as an independent consultancy, helps comply with standards like BS 8233 for building acoustics. It can boost user satisfaction in hybrid setups, where clear audio fosters collaboration and reduces AV call fatigue. 

Overreliance on DSP alone is a false economy. While processors can Equalise (EQ) frequencies or cancel noise, they can't alter physics – hard surfaces reflect sound, creating slap echoes no algorithm fully erases. Acoustic treatments like absorbers, diffusers and bass traps address root causes, complementing DSP for optimal results. In one project for a banking client, we diagnosed high RT60 in a boardroom, recommending targeted panels that dropped it from 1.2 to 0.5 seconds, enhancing STI and privacy without major AV upgrades. The ROI? Reduced complaints, better compliance, and a 20% uptick in meeting efficiency. 

For open-plan offices, sound masking systems introduce subtle background noise to obscure speech, hitting NC-40 levels while preserving intelligibility within zones. In healthcare, we’ve implemented zoned acoustics to safeguard privacy in waiting areas versus consultation rooms. These strategies align with whole-system protection, mitigating risks from data breaches to emergency failures. 

Avoiding Budget Overspend 

To avoid expensive rework, set performance criteria early. Use tools like acoustic modelling software during design phases to predict RT60, STI, and NR/NC. Engage experts for site surveys; pre- and post-installation testing quantifies improvements, proving value to stakeholders. 

At CornerStone, our independence means unbiased advice, blending AV prowess with acoustic expertise for resilient spaces. If you're facing poor sound in your AV setups, consider an early-stage acoustic review or diagnostic testing. These services uncover hidden issues, deliver measurable ROI through enhanced user experience and compliance, and embody our promise of joined-up protection. 

Ready to harmonise your AV and acoustics? Dive deeper into our Audio-Visual services here, Or contact our team to discuss tailored solutions. Let's ensure your spaces not only look impressive but sound exceptional too.