Howto: In-Ceiling Speaker Install – Audio Concepts B-Flat Coax 8″

Audio Concepts B-Flat Coax 8" SquareThis weekend I finally got around to finishing my Audio Concepts B-Flat Coax 8" in-ceiling surround speaker install. I detached the B-Flats from their ceiling mount and stuffed fiberglass insulation (the cotton candy kind, rated R13) in the cavity between ceiling joists. According to the B-Flat installation instructions and in-ceiling/wall tips elsewhere, the insulation should improve sound quality. The end result was not what I expected.

Surround satellite speakers in multi-purpose rooms have always been a problem. Where do you run the long lengths of cable? I’ve tried wireless speaker systems at various frequency and have never heard anything but static. You can try running your speaker cable along your baseboard or even opt for a raceway system like those sold at Cable Organizer. What if you have to jump a doorway, opening to another room or get around a large fireplace’s brick façade? In-ceiling and in-wall speaker installs have the highest wife-acceptance-factor (WAF) because of their invisibility. You get to run your speaker cable inside the wall then to the attic and then back down inside a wall to the speaker.

My in-wall speaker needs first arose with the set-up of my living room home theater in my new house. I had the TV and equipment cabinet against the north wall and needed to get surround sound behind the sofa sectional on the east and west walls. To the east I needed to pass a bank of three windows to the wall area behind our chair-and-a-half. The west side was not so simple. The north end of the living room opened up to our dining room, presenting a 10 ft gap to traverse with no moulding or other architecture to hide wires behind. The living room’s west wall has about six feet before the kitchen’s east entrance. I could hide speaker cable along the east side’s baseboard run. I could do the same on the west side if I ran the wire around the dining room, over the north kitchen entrance, then onto the baseboard of the west wall. This amounted to more cable than I was willing to buy and install.

Running in wall speaker wire through my attic looked like the best solution. Unfortunately, I have no desire to venture into the attic with its past or present wasp nest, blown in insulation and cross beam obstacle course. The trap door to the attic is in the ceiling at the south end of the house opposite the living room. I can’t imagine stepping from ceiling joist to joist without putting a foot through the ceiling. Could I find a compromise between invisible in wall wiring and easy but ugly along the baseboard wire?

DeCorp Dewire is a "thinner than a business card" ribbon of speaker cable that is first glued to your wall or ceiling and then spackled, sanded and painted over for a virtually invisible cable installation. I measured the two runs to my proposed surround speaker locations on either side of the living room. I ordered the Dewire flat speaker cable, their special spray glue, spackle and banana plug and pin terminations. The Dewire would run straight up my wall, across the ceiling and the down each side wall to connect to the speakers. This the same route the in-wall attic run would make but without the attic.

After some searching of the major home electronics magazines and review sites I found little in the way affordable in-wall speaker recommendations. The Audio Asylum and AVS Forum communities pointed me toward the Audio Concepts B-Flat 8" Coaxial In-wall loudspeakers. For under $200 the B-Flat’s promised performance rivaling $1000 in-walls.

After the careful purchase of the surround speakers, the invisible speaker cable and a drywall saw, I failed to ever install the speakers. Other home projects’ precedence was my excuse. Really, I just dreaded the thought of gluing the cable to the wall and ceiling, and then plastering over the wire sloppily and making a mess of my wall. My lack of experience with a trowel and spackle knife paralyzed me.

Months passed. I avoided watching any movies that promised a dynamic and exciting surround mix. I was stuck with stereo. My wife and I endured one romantic comedy after another. Then everything changed.

We refinanced our house last summer including an equity line of credit. My wife got to upgrade our kitchen, hallway bathroom and lighting while I got to build a humble front projection home theater in half of our basement’s rec room.

In this new home theater I could use the B-Flat in-walls as in-ceilings. An in-ceiling install rated high on the WAF scale. Electricians ran the Dewire flat speaker cable through ceiling and out through the square holes they cut for the B-Flats. I was not using the Dewire as intended (glued to a wall and hidden under spackle and paint just like a drywall seam), but I already invested nearly $200 and the Dewire does the same job as in-wall rated speaker cable.

I installed the B-Flats myself after the electricians finished the more difficult hole cutting and wire running part of the process. I simply tightened the four screw posts at each corner. The screws will rotate a clamp that catches and holds the other side of the drywall or ceiling board until tight. An electric screwdriver will speed the tightening of the long screws. You have to balance the coaxial speaker driver and surround in one hand while you tighten the four screws. The only bad part of this process was the extra heat near the ceiling. I was sweaty. I was careful not to over-tighten the screws as the clamp mechanism was all plastic and the ceiling board can easily be crushed back to ripped paper and drywall dust.

Next I calibrated with the Avia Guide to Home Theater DVD. Avia’s 85 db test tones proved stressful for the B-Flats. I detected some clipping when I bumped up the surrounds’ levels to reference level. The clipping is not an issue while watching a DVD or playing a video game. I never raise the volume of the Onkyo TX-DS989 AV receiver above -15 db (0 is reference). The initial calibration pushed the surround levels to +6.5 and +7 (the front stereo channels are set to +4)

After stripping out of my insulation protective gear (gloves, painter’s cap, safety goggles, respirator and Tyvek cover-alls), I recalibrated the surround sound channel balance. To my surprise, the surround levels needed another decibel to reach reference level. I thought they would need less power with the insulation’s damping.

Of course, I have only run the test tones through the B-Flats. I haven’t had the chance to listen to any DVDs yet to see if my insulation made a difference. I am hoping what loudness I lost is gained in clarity, tonal accuracy and imaging.

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