Project Scope
Design an acoustic treatment plan for a middle-school gym to reduce echo and amplify speech.
Project Considerations
- Hard parallel surfaces reflect sound
- High reverberation times can lead to low speech intelligibility
- Incorporate passive amplification for school performances on stage
- $20,000 budget
Measurement Methods
- Laser-measured the room
- Octave-band SPL analysis during a live PE class
- RT60 impulse testing: a clapper hitting 115 dB bursts, a SLM Model 831 measuring across third-octave bands
Analysis Results
- Existing gym T60 time: 5.5 seconds
- Target gym T60 time: 1.7 seconds
- Required absorption treatment: 382.9 metric sabines
Project Summary
This was a MEEM 4704 team project for the CLK middle-school gym in Calumet, MI. The existing gym suffered from a harsh echo that is common in large gym environments with hard flat surfaces and little absorbent material. The district wanted to start using the space for assemblies and needed to reduce echo while increasing intelligibility of spoken voices. To capture the current gym's acoustic profile we laser-measured the room dimensions, ran octave-band SPL analysis during a live PE class, and measured third-octave RT60 bands with an impulse clapper. From there we designed an absorption plan that brought the reverberation down to desired auditorium values while keeping the passive amplification the district wanted for band and theater. Our recommendation for 288 square meters of acoustic curtains lining the walls satisfied the project goals while staying inside the $20,000 budget. We delivered the full report to the district for further action.
