Fixing Echo in Large Auditoriums
Speech echo in auditoriums is usually caused by late reflections from walls and ceilings rather than insufficient speaker volume.
In Simple Terms
If people complain that speech sounds loud but unclear, the problem is reflections bouncing back to the audience. You need absorption, not louder speakers.
Design Considerations
- Large flat walls reflect mid frequencies strongly
- High ceilings create delayed reflections
- Improper speaker angles increase overlap
Practical Recommendations
- Add absorption panels at first reflection points
- Aim speakers toward audience, not walls
- Reduce unnecessary amplifier gain
Technical Notes
- Recommended RT60: 0.8 – 1.2 seconds
- Reflection delay tolerance: < 50 ms
- Speech clarity target STI: > 0.6