In Reply to: Re: Baltic Birch Ply or MDF? posted by Wayne Parham on April 16, 2002 at 00:56:33:
round hole. The holes in the posts easily accepted bare monster cable type wire and clamped very securely, in spite of the "cosmetic only" knurling present. I figured to save time on the cutouts by using my hole saw...then the 260-311 panels were back ordered for 2 weeks:(
I've used acoustic foam, acoustic stuffing, carpet, polyfil and who knows what else inside cabinets. R13 spaced 1 inch from the walls in my 4 Pi Pro's is in another class completely. I almost feel that for a small enclosure, just lining the rear wall with R13 would suffice...
Actually, the R13 might be overkill. At least an extra 3/4 cu.ft. of "apparent box volume" was present when I put 1.2 cu.ft. of R13 into a box whose actual physical net volume was very close to 2.5 cu.ft. This causes your resulting box tuning to be lower than calculated...what boxplot predicted to be a 54-57Hz. Fb measured as about a 40Hz. tuning result. Using an "estimated" Vb of 3.3 cu.ft., ports of another, shorter length were calculated to acheive the desired 54-57Hz. outcome. Again, the box "acted" larger than it's physical size...tuning is now at about 50 Hz...and boxplot claims the woofer should "be happy" where it is now.
Playing with boxplot will show you the consequences of your enclosure tuning being too low(or too high). If you can verify what you have...it might improve your system response, if the tuning is found to be incorrect and then corrected. Sam
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