How to Build Your Own Acoustic Panels (DIY)

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Make Cheap, Easy, Attractive DIY Sound Absorption Wall Panels

Revised and updated May 01, 2021

Also Check out our Complete Guide to Home Theater Acoustics for more information, including where to place your acoustic panels.

Sound absorption panels trap acoustical energy (sound) and prevent it from reflecting off of the surfaces they cover.  The panels are used to eliminate echoes and reflections that muddle or color amplified music and speech.  These wall panels will also reduce reverberation levels in a room, which can sometimes provide ambient noise reduction.*

*Note that choral music, piano, orchestral instruments, group singing, and pipe organ benefit from reasonably reverberant acoustics, with many reflective surfaces.  Installation of sound absorption material can harm musician performance and sound quality for these specific applications.

 Suitable applications for sound absorption panels include:

  • Improving surround-sound imaging and clarity for dvd/blu ray movies, sports, or video games in a home theater
  • Reducing slap-back echo and reverberation in large halls, auditoriums, and contemporary churches
  • Reducing chatter, din, and noise in crowded gathering spaces, restaurants, or bars
  • Providing more accurate listening conditions in recording studios and control rooms

Note that sound absorption material is often called “soundproofing.”  I believe that the term “soundproof” is usually misapplied, which will be discussed in another post.  Sound absorption panels are NOT able to significantly reduce sound transmission through a wall between two adjacent spaces; they are intended to improve sound quality within the room that they are installed by attenuating sound reflections and reducing reverberation/decay times.  If you are looking to reduce sound transmission through a wall, please see our directory of noise control products and solutions here: https://acousticsfreq.com/noise-control-products/  

Commercially-manufactured sound absorption panels are available in two common varieties:

1) Molded melamine foam wedges and eggcrate (e.g. Auralex, Foam Panels, etc.):

Auralex Studiofoam

2) Decorative fabric-wrapped fiberglass panels (e.g. Golterman & Sabo, Wall Technology, Fabricmate, etc.):

Wall Technology Panel

The acoustic properties of each of these are very similar, with all of them absorbing approximately 100% of incident sound energy at mid and upper frequency ranges.  Feel free to compare Sabine absorption coefficients at your leisure.  These material types are mostly differentiated by their visual appearance.

An important consideration for any sound absorption panel, though, is thickness.  A thicker panel will more effectively absorb a longer wavelength (lower frequency) of sound.  Therefore, when choosing an acoustical material, consider the frequency content (tonal spectrum) of sound that you seek to absorb. For placement on drywall surfaces, the following rules of thumb should be helpful:

– For human voices, crowds of people, and speech use 1” absorber thickness

– For amplified music with bass and drums or cinema surround-sound use 2” absorber thickness (or greater)

The necessary quantity and placement of sound absorption material for a given space is determined by the specific type of listening functions occurring there.  Extreme ends of the spectrum range from traditional/classical worship spaces which are entirely hard-surfaced (great for pipe organ and choral music) to THX-certified cinemas and movie theaters which have sound-absorbing materials on all wall, floor, and ceiling surfaces.

Consider which wall and ceiling reflections need to be eliminated and cover those entire areas with sound absorption treatment.

Pricing for manufactured, two-inch thick, fabric-wrapped fiberglass sound absorption panels is usually $6 to $8 per square foot. I have seen sound absorption panels priced as high as $12.25 per square foot! Given the large square foot area that needs to be covered to achieve a suitable home theater acoustic, this falls well outside of the average consumer’s budget.

I may annoy a few people by telling you this, but you can make your own sound absorption panels for MUCH less.  What follows are explanations, instructions, and specifications for very effective sound absorption panels.

The essential elements of a sound absorption panel include:

     1) The sound-absorbing core material (performs the acoustical work)
     2) A sturdy wood frame (holds the fabric tight, provides something to fix mounting hardware to)
     3) An acoustically-transparent, decorative fabric cover (makes it look nice)

 

Step 1:  Select a sound-absorbing core material

The sound absorbing core material must have the following characteristics:

  • Dense fiberglass or mineral fiber board insulation (not loose batt)
  • Unfaced
  • 3lb to 8lb per cubic foot density (6-8 pcf is optimal)
  • 2” thickness

Three acceptable material options include:

Owens Corning Fiberglas 705 6lb pcf, 2″ thick: ~ $3.00 per square foot.

ROCKWOOL/ROXUL Rockboard 80, 8lb pcf, 2″ thick: ~ $1.00 per square foot.

Johns Manville Inusul-Shield 600 2″ UNfaced 6lb pcf, 2″ thick: ~ $3.00 per square foot.

*Note:  Insulation prices can vary greatly depending on your supplier and location, so check into all three or other equivalent 3.0-8.0 lb fiberglass or mineral fiber insulation board products.

**Also Note:  Fiberglass and mineral fiber insulation are known irritants.  Please wear a mask, gloves, and glasses when handling the insulation.  Follow the manufactures guidelines for safe usage.

You can usually find the best prices for these insulation products at your local insulation supply dealer.

Click to find dealer locators for:  Johns Manville  –  Owens Corning  –  ROCKWOOL

My prototype panels were built with the Roxul RHT 80 insulation, which is the least expensive sound absorption material that I have found.  The Roxul acoustical performance is similar to the Owens Corning and Johns Manville products, but it is softer and has a less regular shape.  The manufacturer-supplied sound absorption coefficients are as follows:

2″ Roxul RHT 80       2” Owens Corning 705        2” Johns Manville 817
125 Hz = 0.39             125 Hz = 0.16                          125 Hz = 0.38
250 Hz = 0.84             250 Hz = 0.71                         250 Hz = 0.93
500 Hz = 1.08             500 Hz = 1.02                         500 Hz = 1.10
1000 Hz = 1.01          1000 Hz = 1.01                       1000 Hz = 1.07
2000 Hz = 1.02          2000 Hz = 0.99                       2000 Hz = 1.07
4000 Hz = 1.01          4000 Hz = 0.99                       4000 Hz = 1.07

Sabine absorption coefficients are roughly the ratio of reflected sound absorbed.  So, at a given frequency range, a 1.00 coefficient equals a 100% absorption rate* (0.71 equals 71%, etc)*.  Note that these figures are provided by the individual manufacturers and tested in different labs.  It is safe to assume that each of these materials is equivalent to the others.

*Edit: Sabine absorption coefficients are not a true energy absorption coefficient and can exceed 1.00.  Therefore the translation into % absorption of reflected sound energy is not quite accurate from a physics perspective.  However, for the purposes of acoustical design in architecture it is a good way to understand and compare different materials.

Step 2:  Build a wood frame around each panel

For the wood frame, I used a 1” x 2” furring strip, which is inexpensive and available at any hardware store/lumber supplier.  Due to actual dimensions being less than nominal, a 2″ deep furring strip will give the finished panel a “beveled edge” appearance.  A 3″ deep furring strip will give the panel a perfectly flat face.  Carefully check each strip to ensure that it is straight and not missing significant chunks of wood.
  1. For each panel frame, cut two segments of furring strip to 49-3/8” and two segments to 24” (check measurements with your sound insulation panel and furring dimensions).  Measure and cut to ensure a snug fit around the insulation.
  2. Apply a heavy dose of spray adhesive to entire perimeter of insulation (NOT THE FRONT FACE). (glue will hold the insulation in position within the frame).
  3. Position the insulation such that the bottom face of the panel is flat and level with the wood frame.
  4. Arrange wood segments around the fiberglass panel.  You will want the frame to secure tightly around the insulation, compressing it slightly.
  5. For each corner:
    • Pre-drill a pilot hole for one corner to ensure alignment and prevent the wood from splitting.
    • Apply wood glue.
    • Screw wood segments together.
  6. Allow 24 hours for wood glue and spray adhesive to dry.

 Step 3:  Select a sound-transparent fabric; wrap the panel

The purpose of the fabric cover is to give the panel a handsome, decorative appearance. To ensure that sound penetrates through to your fiberglass insulation (rather than reflects off the surface), you must ensure that your fabric is acoustically transparent.  A simple way to test this is to hold the fabric to your mouth and exhale through it.  You will sense a level of airflow resistance through the fabric.  Select a material with very little resistance.  Solid vinyl, leather, or acrylic-backed fabric is not acceptable for this application.

The most common fabric choice for commercial panel manufacturers is Guilford of Maine Panel Textiles.  This is a high-quality material.  That being said, there are a great variety of inexpensive fabrics that can work equally well.  Colored burlap is a very common choice.  My prototype panels use a Keepsake Calico paisley material purchased from a local fabric store.  Considerations for your fabric cover:

  • Must be “breathable” and sound-transparent
  • Ensure that your fiberglass panel is not visible through the fabric
  • Beware that fabric with visual patterns will be tricky to line up squarely when stretched over the wood frame

To stretch the fabric to your panel:

  1. Lay a 62” length of fabric (face down) on the floor.
  2. Place your framed panel on top of the fabric with the flat/level/even side facing up.
  3. Have a friend wrap the fabric around the backside of the panel and staple it to the wood frame every 3” along one of the edges.
  4. Stretch the fabric tightly along the opposite edge and staple, continuing along the panel edge at 3” intervals.
  5. Repeat steps 3 and 4 for the top and bottom edges, taking care to neatly fold each corner.
  6. Apply spray adhesive underneath the remaining loose fabric areas on the back side of the panel.

NOTE:  Apply spray adhesive to BACK side only, NOT front face.

Panel Back

Panel Front

Step 4:  Mount the panel to your wall or ceiling

Detailed steps for finding the best placement locations for sound absorption panels in a home theater can be found in our detailed article: Where to Place Sound Absorption Panels in a Home Theater.  Note:  Adding a small airspace (1.0 to 2.0 inches) behind the panel will significantly improve low frequency sound absorption performance.

These panels can be mounted similarly to a heavy piece of artwork.  Use your discretion and judgement to make sure that your panel is safe, secure, and stable.  I screwed two heavy-duty D-Ring hangers on each side of the wood frame, measured to exact spacing. These were hung on two 20-lb rated picture hangers.  See the Equipment List below for hardware recommendations.

Step 5: Listen

Now you are ready to enjoy your music or home theater the way that it was intended. Most people are surprised to hear what music and movies sound like in a properly-treated acoustic environment. The audible difference cannot be overstated; it is like night and day.

 You will probably need quite a few of these panels to get the desired outcome, so repeat the above steps in an efficient assembly-line process until you have treated all of the desired wall and ceiling surfaces.

 

June 4, 2014 update:

Here are some photos from a recent build by our reader Mike:

photo 1 photo 2 photo 3

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