Article by Jeff Hedback 

For nearly 90 years materials have been specifically placed in recording environments to create more balanced and beautiful recordings.  Before that time, the highest levels of architects and craftsmen were selected to create the world's music halls.  Here we are in the 21st century with the ability to create, capture and distribute music from a bedroom to the entire world.  So why can't I go DIY with acoustical materials?  The answer is you can.  However you may want the rest the story before you embark.  The following is a summary of a job I completed a few months ago where we converted a wine cellar to a drum room.  The results are tremendous…the effort…tremendous…you read and you decide on your own needs.

Client: father and former drummer wants to create a drum practice/jam room for teenage son.

Space: 18'-4" L  x  9'-5" W  x  9'-7" H.  Drywall walls/ceiling with no insulation and an imported ceramic tile floor.  The house itself is in an upper income golf community and has high-quality finishes (flooring, woodwork, etc…)

Goal: reduce any practical amount of sound transmission to other areas of the house (but cannot build any new structure).  Improve the quality of sound within the space for drum practice and rock band applications.

Plan: diagnose the space, create a concept, get clients approval of concept, fabricate and install.

Diagnose: as an acoustician, I began with the room measurements and ran modal analysis to see what is likely going on with the low frequency peaks and cancelations.  The results were to be expected in a room where the width and height are nearly the same.  While in the room, it was very disturbing to converse.  My voice was at the same time resonant and hollow.  Also, the tile floor added harshness to sibilance frequencies.  In terms of sound isolation, it was a matter of setting expectations: there is no way to get a high degree of isolation without building a room-in-room.  But, treatments above 60% of room surfaces with proper low-mid and bass frequency control will muffle sound to other areas.  It was also determined that the existing solid core doors could be sealed to help the cause.

Concept: Here's where the DIY comes in.  Although I am a professional acoustical designer, all the elements in this job were purchased at Lowes, Home Depot and JoAnn Fabric.  Well, technically not true…the acoustical absorbers were sourced (more on that below).  Let's begin with the basic design: create 4'x4'x4" wood frame panels to install at diagonals.  There placement is to be asymmetrical between parallel walls.  Four 6'x1'x6" bass traps are to be located in corners.  The drum kit itself is to rest on an Auralex PLATFOAM high-density foam riser.

Fabrication:  the client selected fabrics from JoAnn fabric with the criteria that they must be able to freely feel their breath through the fabric.  They selected a micro Suede and a cotton weave.  The suede was then planned for the ceiling panels and the corner traps with the cotton basket weave fabric to be the wall panels.  1x4 and 1x6 lumber was calculated and pre-cut.  ¼" pegboard was selected for the panel backs to increase bass absorption.

Behind the Science: this job used three primary acoustical absorbers: (1) 8# density Mineral Fiber, (2) 4# density rigid fiberglass and (3) Auralex 4.5" thick acoustical foam.  You can guess that Auralex foam is available through a retailer.  In this case, Auralex MAX-Wall panels were available to be repurposed through a handy electrical carving knife.  The corner bass traps were packed with the Auralex.   Both the other absorbers can be difficult to source.  Auralex does offer the Mineral Fiber (primarily used for sound isolation wall insulation).  The rigid fiberglass is best found at commercial insulation supply houses…not easy to get, but certainly possible with a connection or two.  Why the different densities and materials???  That is the science and this is not the article to cover that in depth…simply said: this room requires a multi-front attack to contain the modes for drum application.

Fabrication time and material cost:  Fabrication time of panels approximately 90 hours, installation time 14 hours (two men 7 hours), material cost $1,000.  Not included is the time and expense traveling to five different JoAnn stores to find all of the material needed for the job.  Also, the "art" of stretching fabric should not be taken lightly.

Results: the room sounds #$%^&* awesome!!!  In one sense it's a shame it is for a teenage kid.  On the other hand, it is a tremendous space to learn the craft and discipline of music (I'm a bit jealous).  The modes are even…no more hollow, no more boomy.  The riser took care of most of the rumble to the rest of the house and left and tight articulate total kit sound.  The snare…the snare sounds incredible.  The tile has become an amazing and unexpected wow factor.  It now imparts a rich a complex texture to the snare.  You could take three mics and get a drum sound for any level project.

Was it worth it…absolutely.  There are not retail acoustic products available to get this result without spending upwards of $5K.  We are talking about 200 sq ft of acoustical treatment.  The use of hard and soft combined with the diagonal panel placement offer a wonderful blend of diffusion and diffraction.  The bass response is tight.  The midrange character is very open and articulate.  The upper mids and high frequencies are still balanced and present without being harsh.  The fabrics look tremendous and remained acoustically transparent.  The client and his son are thrilled…Absolutely worth it!

What does this mean to your room?  Simply, if this room profile gets your imagination in gear, gets your handyman skills pumping and gets your desire for excellence ramped up; then you are the next acoustical treatment DIY candidate.

Jeff Hedback is Chief Designer at www.HedbackDesignedAcoustics.com a full service acoustical design and consultation firm specializing in small room acoustics.