Maybe this is where I should be asking this

[Markyboy]

I have been reading a lot of these posts and decided that this is where I need to be asking this:

I am building a pair of cabinets to flank my TV and house my components, DVDs, CDs, and KM-2s. I have gotten a few different opinions which I really appreciate and have halted construction until I've gotten a few more. Many people have said not to put the speakers into the cabinets because they are rear-ported and will sound "tubbish". Others have said you could do it but just to completely open the rear of the compartment that the speaker will be in. And still others have said that I should build the compartment tight enough that the speaker looks built-in. I am even entertaining the idea of lining the compartment with an absorbent material (foam, egg crate, etc.) and rerouting the porting to the front or extending the porting out the back using PVC or some other flexible material. I should say the the speakers' dimensions are roughly 13"h x 9"w x 9.5"d. The cabinets will be 48"h x 20"w x 24"d. I wanted to use the top shelf as the location for the mains because that would put them at the proper listening height.

I would LOVE to hear any more thoughts on the subject. I have seen some ingenious ideas come from this section and was hoping someone could help me out.

Thanks in advance.

[colterphoto1]

Hey again Marky, I responded earlier to your post and you're smart in bringing it up in another forum if ya didn't like what you heard. I was in favor of a fairly tight speaker to furniture fit, eliminating the rear port 'wrap around' effect within a larger furniture cavity with back, and opting instead for an open furniture back where the port could naturally 'breathe' to the room.

Remember this about port design, it is not simply an area or diameter, it is a VOLUME, think of it as a mass of air, a physical piston that is pumping out that low bass that we love. When you look at the way Klipsch created your bass port (with tube or wooden 'tunnel'), you will realize that you may not simply redirect or create a longer pathway for the bass to escape, you are then changing the volume of the port by lengthening it and changing the tuning of your system.

From a listening standpoint, where the port exits the cabinet naturally should couple with room air as directly and openly as possible, hence my earlier advice. But, hey, maybe others have other options for you. This is also possibly why Klipsch moved the ports to the front in most (?) of the newer Reference series. I myself have RC7 in a console for 35" tv, and I have both a partial open back to the cabinet, breathing room around the cabinet, and some absorbent material around it to help break up the 'tubby' sound.

Hope this helps.

[Markyboy]

CP-

It's not that I didn't like what I heard. I like having as much information as possible before investing the time, money and effort into something as important as this. Are RC7s rear-ported as well? If so, did what you did (open back, room to breathe, lining the cabinet) work to help with the "tubbiness"? Thanks.

[colterphoto1]

In may case did all, the cabinet itself (factory cab for sony 35") had a shelf which had to be removed. I build custom slanted shelf to tip center speaker to ear position, put a small rug on bottom, and there's about a 4x10 punchout in the back for wiring. This cabinet has angled speaker and two angled walls however (top view, it's kind of rhombus shaped, 32" across front, about 24 across back. so both sides are angled) which I think helps with the 'tub sound' since there's no ringing of those honky sounding mid-bass tones like you'd have in a rectangular box.

Go back to my other post, I put speakers in entertainment centers twice. The one where speaker was in totally sealed shelving box was HORRIBLE, the one with speaker tightly fit (you had to slide speaker in from back of cabinet and I used 1x2 poplar for shelf edging to strengthen 3/4 ply shelves) and NO BACK for the speaker portion of entertainment unit was WONDERFUL. you decide, but I only used like 1/4 ply for back (mostly for diagonal strength and to keep record albums from sliding out the back of their section) so all component sections and speaker areas had no back. Another think that looks good is put a back on component section but leave about a two inch wide slot to route wires, they will look nearly invisible from front.

hope this helps. like I said just put your speakers in any box or kitchen cabinet and fire em up if you want to see what it's going to sound like.

[michaelstano]

I am not a sound engineer, so this may be really naive: Assuming the cabinet is not totally against (or built into) the wall, why can't the port be extended to exit the cabinet? This would seem to more closely replicate what the original, unobstructed speaker was meant to do.

[colterphoto1]

reread my post from 9/11