ssh Posted February 24, 2003 Share Posted February 24, 2003 I've been lamenting a loss of bass with my Khorns in a remodeled room.After planting them on 3'x3' squares of 3/4" plywood and getting some,but not enough,improvement,I got a flashlight and looked behind them.One wall drifts out towards the bottom,leaving an angle to fill.I had already bought automotive weatherstriping,but this is a gap of inches.Should I strip a piece of wood at that angle and attach it to the bach of the speaker?Use Liquid Nails?I tried searching the archives,but didn't use the right words to match. Quote Link to comment Share on other sites More sharing options...
Parrot Posted February 24, 2003 Share Posted February 24, 2003 If you happen to own this home, would it be possible for you to repair the wall? If it slopes inches over a three or four feet length, that wall needs some help. Quote Link to comment Share on other sites More sharing options...
ssh Posted February 24, 2003 Author Share Posted February 24, 2003 That's not an option.The sole plate apparently kicked out before we nailed it,& we didn't notice.The corner is very tight,with 2 layers of sound board & sheetrock. Quote Link to comment Share on other sites More sharing options...
ricktate Posted February 24, 2003 Share Posted February 24, 2003 can you show us a picture,,,,,not sure if its that bad,,,,,maybe out of phase wire hook up to,,,,rick Quote Link to comment Share on other sites More sharing options...
artto Posted February 24, 2003 Share Posted February 24, 2003 The proximity of the woofer horn to the walls at a corner has a significant effect on the frequency response of the Klipschorn. If the Klipschorn is not properly seated in a corner there will result a response dip in the region of 250-500 cycles per second in the Klipschorn woofer. A one inch gap on one side can cause a 7 decibel loss at 500 cycles per second. Where a fit cannot be affected, one may apply a flap of flexible but firm sheeting, such as U.S. Rubber Companys one-eight inch gasket. Most important, however, is the fit against the corner.(Klipsch Dope From Hope publication Vol. 2, No 12, November 1961). You can find something similar at hardware/building supply stores thats used as stair tread covering to prevent slipping & wear. Like the black rubber covering some people use on their basement stairs. Carpet protector covering should work equally well. Or possibly even a heavy weight building/roofing felt. You could also make a corner plate out of 2"x10" or 2x12 wood, angled (beveled) at the edges to fit the corner. Use some weather striping on the beveled edge to seal it air tight against the wall. Bolt the corner plate securely to the wall, preferably into the wall's studs. If you want, you can also then bolt the Khorn's tailboard to the corner plate. In my experience, this has yielded the added benefit of improved midrange/treble performance for some reason. More detail, greater clairity. The only thing I can figure is that this must be stablizing & damping vibration of the entire speaker system. I guess you could consider it similar to a technique thats known as "mass loading". Except in this case, the speaker is basically damped by physically connecting it to the mass of the house & earth. Doing this with a strong physical connection to the foundation (as in a partial below grade or basement condition) works best. If the gap is too big it may be best to fill it in. You can "build-up" some layers with cheap wood lath & plaster over it. Quote Link to comment Share on other sites More sharing options...
ssh Posted February 24, 2003 Author Share Posted February 24, 2003 Good suggestion,but I've checked.No pics now,but I may take off the side panel & shoot one. Quote Link to comment Share on other sites More sharing options...
ricktate Posted February 24, 2003 Share Posted February 24, 2003 Does the sqaure plywood you put on bottom of speaker touch the wall on the sides......did you put grippers or rubber on bottom of k-horn,,like hdbr advised?..I have put grippers on my LaScalas and wow...also hk430 reciever will help to....it has good clean power and cheap to...still need a picture to see what is going on though...rick Quote Link to comment Share on other sites More sharing options...
ssh Posted February 24, 2003 Author Share Posted February 24, 2003 I considered a corner plate similar to what you describe,but just don't want to rework the walls.The build-up specifics help a lot.I had in mind to use wood,but your suggestions may be better materials. Quote Link to comment Share on other sites More sharing options...
ssh Posted February 24, 2003 Author Share Posted February 24, 2003 I have weatherstrip for the bottom,too,but when I saw the gap,I knew that I had to deal with that first.My receiver is a Marantz 9200,& Craig has my Bogen 230A to rebuild. Quote Link to comment Share on other sites More sharing options...
ricktate Posted February 24, 2003 Share Posted February 24, 2003 Are you talking about the tailboard,,,gap at bottom next floor..or gap running away from the corner of wall,like the corner is not sqaure?If its just the wall not being plumb at the tailboard rubber stripping on tail board would fix it.....hope this helps..rick Quote Link to comment Share on other sites More sharing options...
Mallette Posted February 24, 2003 Share Posted February 24, 2003 This is an area which interests me. I too feel my 'horns are a bit bass shy. I've applied 8db boost at 80hz and it works well, but being a bit of a purist would rather not have to. Mine are on carpet, so the plywood would probably help. What I've not understood is just where weatherstipping or other sealer might applied. The grillcloth doesn't quite touch the wall, but I don't see this as relevant since the grillcloth is open anyway. OTOH, I don't see anywhere else one might seal the bass exit to the wall. Explain? Dave Quote Link to comment Share on other sites More sharing options...
ricktate Posted February 24, 2003 Share Posted February 24, 2003 Mallet,,you have to seal tail board to the corner of the wall...k-horns come with gasket to do this but usually gets lost or not installed....think of it like this you have two sides and need to seprate the sides at the corner of the room....rick Quote Link to comment Share on other sites More sharing options...
Mallette Posted February 24, 2003 Share Posted February 24, 2003 This is an area which interests me. I too feel my 'horns are a bit bass shy. I've applied 8db boost at 80hz and it works well, but being a bit of a purist would rather not have to. Mine are on carpet, so the plywood would probably help. What I've not understood is just where weatherstipping or other sealer might applied. The grillcloth doesn't quite touch the wall, but I don't see this as relevant since the grillcloth is open anyway. OTOH, I don't see anywhere else one might seal the bass exit to the wall. Explain? Dave Quote Link to comment Share on other sites More sharing options...
ricktate Posted February 24, 2003 Share Posted February 24, 2003 As long as you have tailboard sealed to corner good,,,the sqaurness of the wall should not matter all that much....never seen a wall stay square anyway,,wood warps,foundation moves,etc...But the tailboard needs a good seal on both sides of the edge of it to help the bass bin work,,,also check polarty of wires to speaker and woofer,,,more than a few members here have found wires wrong....rick Quote Link to comment Share on other sites More sharing options...
Chris Robinson Posted February 24, 2003 Share Posted February 24, 2003 Dave, don't forget, the horizontal plywood piece that makes up the bottom plane of the HF section (in my KCBR's anyway) needs to be sealed. IOW, you need a vertical seal along the edge of the tailboard AND a horizontal seal starting where the tailboat and the HF box intersect. If done right with suitable material, it should be very effective (I used sticky-backed 3/4" foam insulation, $3 at Home Depot). I've got an immense amount of bass coming from these bins. Quote Link to comment Share on other sites More sharing options...
ssh Posted February 24, 2003 Author Share Posted February 24, 2003 Rick, The corner isn't square.Dave,After installing the plywood,I found that while my carpet was absorbing a noticable amount of bass,that was only part of my loss.I was following suggestions from HDBR in an earlier post,and was about to apply rubber automotive weatherstriping on the tailboard & flat weatherstriping under the bottom,when I noticed the gap. Quote Link to comment Share on other sites More sharing options...
Mallette Posted February 24, 2003 Share Posted February 24, 2003 >Dave, don't forget, the horizontal plywood piece that makes up the bottom plane of the HF section (in my KCBR's anyway) needs to be sealed. To what? Speaker, or wall? >IOW, you need a vertical seal along the edge of the tailboard AND a horizontal seal starting where the tailboat and the HF box intersect. By "tailboard," do you mean the 6" by 3' or so framed grill vent? The top part I can follow. Dave Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted February 24, 2003 Share Posted February 24, 2003 There are a few things you can do to improve bass response in khorns. First, understand that they will not produce significant output at 20hz, so if you want earthquakes car wrecks or explosions, you are probably out of luck. The corner fit is important, as mentioned several times before. I have used thick felt available from a hardware store house insulation area with good success, but my walls are fairly plumb. Put some foam tape along the horizontal section of the squawker, to help seal the bass bin from the rest of the speaker. Adding a 3' strip of R13 fibreglass insulation to the rear chamber for the woofer making it about 1/2 full of insulation helped somewhat. You're playing with the loading of the bass speaker, so you are second guessing PWK but I think a bit of extra loading is OK. While I was in there, I put strips of dynamat on the woofer basket. Dunno if this helped, but there ya go. Having an adequately sized room is essential. Bigger is better for holding those low freq. waves. 20+ feet is a bare minimum, IMHO. Much has been said about room dimensions, the idea being to avoid symmetry as much as possible. 20x20 rooms are bad, 20x29 rooms are good. Or like that. Some might disagree, but having very solid walls (or a basement with earth on the outside walls) helps to hold in the really low bass and makes the most of what you get. Speaking of basements, the ceiling often is floor joists and they suck up the bass. I haven't done anything with mine, but someday when I wouldn't mind having fibreglass rain down on me I'll stuff the joists with insulation to reduce the congestion up there. Someday. This is dumb, but make sure both speakers are in phase, as well as all the drivers. I had my left bass driver out of phase with my right bass driver for a long time w/o noticing. Don't let this happen to you. Finally, if you have done all this and still feel you want more bass, just do what I do: lie down on the sofa with a cold compress on your forehead and wait for the feeling to go away. Quote Link to comment Share on other sites More sharing options...
ricktate Posted February 24, 2003 Share Posted February 24, 2003 NO ..the tailboard is the piece of wood that is into the corner...the very back of speaker...there should be a gasket there,,,,and along the top and bottom to if you want more out of the bass bin....but the wall not being square can be fixed by rubber gasket along the horizontal edge of bass bin no problem.......rick Quote Link to comment Share on other sites More sharing options...
Mallette Posted February 24, 2003 Share Posted February 24, 2003 Alrighty, sir. I see the light...shining through the 3/4 inch gap between said board and wall. Now, what about the base plywood. Where should a seal be applied there? Dave Quote Link to comment Share on other sites More sharing options...
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