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Learning center / Acoustics by building type / Lecture hall and auditorium

Acoustic panels for lecture halls: the complete guide

What makes lecture halls noisy, which panels fix it, and how to plan treatment from start to finish.

2 minute read · Updated Nov 2026

Speech that carries to the back row without a boomy room. Acoustic panels do that by absorbing sound energy that would otherwise bounce between hard surfaces. In lecture halls the main sound sources are the presenter and the sound system, and the most common complaints are that the back wall sends a late echo to the stage, speech is clear near the front only, and that the sound system feeds back.

What is going wrong in the room

Every hard surface reflects sound. When a room has a lot of them, each sound keeps bouncing for a long time and overlaps the next one. That build-up is called reverberation, and it is measured as RT60: the time it takes a sound to fade by 60 decibels. A typical lecture hall of 70 × 50 ft with a 18 ft ceiling has a volume of about 63,000 ft³. With typical surfaces (drywall, a rug and some furniture), its echo time is about 2.73 seconds. The target for lecture halls is 0.90 seconds.

What panels can and cannot do

  • Panels can shorten reverberation, remove flutter echo, make speech clearer and lower the overall noise level that builds up in the room.
  • Panels cannot stop sound passing through walls, floors or doors. That is soundproofing, which needs mass, airtightness and isolation. See soundproofing and STC for lecture halls.

The recommended starting point

For a lecture hall like the one above, we suggest about 80 48 × 96 in rectangular panel, 2 in thicks, which brings the echo time down to about 0.90 s. That is roughly 59% of the wall area if the panels went on the walls. A good split for lecture halls is about 70% on walls and 30% on the ceiling.

Open the designer with this setup loaded, or browse ready-made models on our lecture hall and auditorium solutions page.

Plan it in five steps

  1. Measure the room and note what the floor, walls and ceiling are made of.
  2. Work out how many panels you need with the room calculator or the worked example for lecture halls.
  3. Decide where they go, starting with the placement guide.
  4. Choose thickness, fabric and color to suit the room and its cleaning needs.
  5. Check the fire and code requirements before you order.

Guides for lecture halls