Next was the frame build.

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1 Just wanted to share my DIY acoustic panel build project for our theater area. I knew I needed some acoustical help because I could hear muddy sounds, echoing and reverb as the sound level is increased. Gets difficult to listen to if volume is turned up too much. Sound becomes harsh. Not that we watch our movies that loud, but I do like to feel a sound track. The MCACC in the Pioneer SC07 does a good job, but it can t completely correct an inherently bad sounding room. And our room is definitely acoustically challenged! So I ve been reading the DIY threads here and researching online as to how to build myself. I considered buying finished panels, but was intrigued by the DIY project and the opportunity to save some dollars. It s really not a difficult build, just takes a commitment of time, some basic tools and a bit of wood framing experience. I know there s other DIY acoustical panel build threads already, but wanted to share my version of the project. After doing some research, I chose Roxul Rockboard 60 vs. rigid fiberglass for the acoustical material. This had the best combination of price, acoustical properties and workability. The chart on the ATS Acoustics website (no affiliation) was a great help ( Right-Acoustic-Material--ac.html). Panels are 2 x 4 x 2. These are purchased in a box of six panels, and if your patient, you can purchased these for a sale/clearance price under $40/carton. I did some trials with the raw/unframed panels to test different positions and heights. I knew I wanted panels behind each Rti12 and under the TV (behind the CsiA6). I also knew I needed panels on the side wall next to the seating area. I used a mirror to find the first reflection point of both towers for the prime seating area which is back row center. The first two panels towards the front are those reflection points; I added a third panel to balance the aesthetics (but it obviously helps with the acoustics too!). Next was the frame build.

2 Research seems to consistently recommend a gap behind the panels equal to the thickness of the panels. As you will see, I had the opportunity to obtain that in the front two panels, but the rest, on the sump pump closet door and side wall, needed to hug the wall much closer. I chose to use 2 x 3 x 1 pine for the frames. This allowed a gap of approx. ½ behind these panels. Frames were built to be same size as the panels so they would snuggly slide right in. In retrospect; I should have made them approx. 1/8 smaller overall so the panels would fit more snug. Corners of frames were initially nailed (pneumatic nail gun) and glued, but I also used 2 deck screws in each corner to ensure the joints were strong. All screw locations were predrilled and countersunk to avoid wood splitting and to maintain a smooth surface for fabric wrapping. I sanded all edges to remove any sharpness. At this time I was still unsure which fabric I was ultimately going to wrap them with, so in case I used a thinner speaker cloth, I didn t want to leave any sharp edges to potentially tear the fabric. Knowing that the panels were not as tight in the frames as I would have liked, I drilled and counter bored, in strategic locations, around each frame so once the panel was installed I could hammer a 3 nail through the frame and into the edge of the panel to hold it in place. I use a drilled pilot hole so I didn t need to hammer very hard on the side of an unsupported 1 thick frame. The counter bore was to keep the nail head from protruding from the surface of the frame. Close up picture below. I painted the edges of the frames; again, just in case I used a thinner black speaker fabric (which I was considering), I didn t want the light colored wood frame to show through. The three side panels were going to be positioned such that they spanned the wainscoting and chair rail molding. These panels were notched to fit around the molding and sawed about ¼ shallower on the bottom half of the frame to compensate for the thickness of the wainscoting paneling. The result is a very nice consistent flat fit to the wall. Notice I painted the notched area of the frame the matching wall color incase some of this surface showed through when I cut/notched and stapled the fabric around this contour. As it turns out, it was not needed. I figured out a clean way to accomplish the tucking, trimming and stapling around the contour.

3 To hang the panels on the wall, I wanted a system to easily remove if necessary, yet robust in reliability, so I chose to use interlocking blocks. I used leftover 2x4 s from another project (don t we all have leftover pieces of 2x4 lying around from something.). I sawed approx. a 30 degree angle through the 2x4 block and mounted one half to the wall. Without the panel in the frame, I held the frame in place and leveled, then drilled in the mounting screws for the mating block. Still did some fine tune leveling with a little square of cardboard, but that s just because I m that anal. There was more than enough room for the two front panels to be hung in front of the molding and wainscoting vs. being notched. This simplified the hang and I got a 2 gap behind. It also hides the power and HDMI cords from the TV without having to chop into the wall. Legs were needed at the bottom of these two panels to keep them hanging vertical. For these I used ¼ x 3.5 lag screws with a cabinet door self adhesive bumper stuck on the head. This worked great because I could hang the frame and adjust the extension of the legs with a wrench to get the frame perfectly vertical. Noticed I painted the mounting blocks and leg for the end panel so they were less visible from the side.

4 Next came the final assembly. I pushed the panels into the frames and installed the nails around the edge. No glue, no mess. The mineral wool is also not as difficult to work with from a standpoint of itchiness and breathing protection so long as you re careful with the handling. I hung the panels without the fabric covering until the material arrived and the schedule permitted time to finish. Note the panel on the door which is notched to fit around the door knob. I chose to use a heavy black speaker fabric on the panel directly under the TV to continue the black color down behind the equipment cabinet, but used acoustic micro-suede fabric for the other panels. Couldn t find the right color in speaker fabric, but did so with micro-suede. The micro-suede color matches nicely with the wall color. I used a staple gun to attach the fabric to the frame and figured out a way to neatly fold the corners. You want to make sure the fabric is tight, but don t over stretch. That can caused bowing of the frame, waviness in the fabric, tearing of the fabric on corners, tearing of the fabric around the staples, etc. The picture on the left is of the frame/panel just before stapling of the fabric. The picture on the right is just after finishing. A large flat surface is essentially to keep the fabric flat while pulling and stapling.

5 Final product is a very nice looking set of panels that I m proud to say I built myself. From a sound improvement standpoint, I noticed a difference immediately. Sound was cleaner and bass was sharper. I know 2 thick panels are more for mid and high range and less for bass (bass traps are for bass) but the bass is definitely improved. I still need more panels distributed around the rest of the room. There s still a lot of sound bouncing around, but this has been a great start and fun project.