Building DIY acoustic panels

Hard walls make a room echo. Dialogue gets muddy, and good speakers sound worse than they should. Acoustic panels are the fix, and building them costs a fraction of what you'd pay for ready-made ones.

Materials for four 2 x 4 ft panels

• Rigid mineral wool or fiberglass board, 2 inches thick (Rockwool Safe'n'Sound is a common choice)
• 1x4 lumber for the frame
• Wood glue and screws
• Breathable fabric. Cotton, burlap or speaker-grill cloth all work. Avoid anything that doesn't let air through.
• Staple gun
• Gloves and a dust mask while you handle the insulation

Build

1. Cut the lumber to make four frames. Each should be just a little bigger than the insulation so it fits snugly.
2. Glue and screw each frame together.
3. Fit the insulation inside. If it's loose, a few staples of fabric over the back will hold it.
4. Wrap the front with fabric and staple it around the back edge, pulling it tight and flat.
5. Add hanging hardware to the back.

Where to put them

Start at the first reflection points. Sit in your main seat and have someone slide a mirror along the side walls. Wherever you can see a speaker in the mirror, that's a spot for a panel. Then add some on the wall behind you.

Don't cover every surface. A room that's too dead sounds lifeless, so add a few panels, listen, and then add more if you need to.