Timmikid Posted March 12, 2010 Share Posted March 12, 2010 Hi all. I probably know the answer to this, but think with me. I just moved to a top story building where the back wall starts to tilt inwards, because the pointed roof starts there. So... My Khorns are snug/sealed to the side walls, but at the back there is an opening. Snug at the top, but a serious few inches of space at the bottom. I guess the only way is to build a straight (false) wall at the back? One more question. How long should the falls walls extend beyond the speakers, or is it most important that the seal is there? Thanks, Tim. Quote Link to comment Share on other sites More sharing options...
DrWho Posted March 12, 2010 Share Posted March 12, 2010 As long as you're close to the wall, the length of the false wall on the back isn't going to be a big deal. The seal on the back is definitely the most important. There was an article on it in the Dope From Hope and I seem to recall using a 48" piece of wood...but probably because it's a convenient size. Someone with the article handy can probably confirm the actual dimension. Quote Link to comment Share on other sites More sharing options...
garyrc Posted March 12, 2010 Share Posted March 12, 2010 The K-horn manual suggests standard 4 foot wide sheets of 3/4" plywood over 2x4 studs, with 1/2 " plywood over the back surface for extra rigidity. The y suggest a height from 39" to 52 inches or more. 52" is the height of the average K-horn. 52, or whatever takes you to the top surface of your K-horn looks good. For many reasons that have been discussed on the forum and in magazines, I'd be tempted to: Use 3/4 ply front and back ... the K-horn can shiver the timbers of a well made house ... the front and tops could be Oak or Walnut skinned an stained Make the corners extend 5 feet, rather than 4 -- as suggested by at least one magizine article ... I believe PWK said the false corner would produce 90% of the performance .. 5 feet might approach 100%??? Use rubber seals (water pipe insulation) on the tailboard and the horizontal member just above the bass bin (not the top of the whole cab). Klipsch support has drawings. Push the K-horns into the false corner untill the rubber is well compressed place the corner and the K-horn on the bare floor, not carpet, to prevent any subtle rocking back and forth ... the carpet (which you definately should have, accordintg to Heyser) can start just a bit out from the K-horn If the part of the ceiling that will bounce the tweeter wave to your ears is lower than Klipsch's recommended 8.5 feet, put a little absorbtion or diffusion there (have someone hold a mirror flat on the ceiling and move it around --- when you can see the tweeter/mid part of the K-horn from a listening chair, the mirror is covering the spot on the ceiling that should get treated. If you do all of that, it is conceivable that the sloping wall could actually improve the acoustics (between the K-horns, and anywhere except the front corners. Quote Link to comment Share on other sites More sharing options...
gaspr Posted March 12, 2010 Share Posted March 12, 2010 Snug at the top, but a serious few inches of space at the bottom. I guess the only way is to build a straight (false) wall at the back? I am assuming that your new place is a rental? If so, my suggestion would be to purchase some foamboard insulation and cut it to fit tightly to the wall where the gap is. It would not have to extend beyond the speaker at all as you are within inches of the back wall and would achieve most of the corner loading that is available. Or...you could leave the top portions unattached to the bass bins and then maybe the bass bins would be able to fit snugly against the back wall?? Or...one last suggestion...simply attach enough plywood to cover the half of the bass bin that is not snug to the wall...again, extending this beyond the speaker itself would have limited usefulness. Good luck to you. Quote Link to comment Share on other sites More sharing options...
JJkizak Posted March 12, 2010 Share Posted March 12, 2010 I'd hate to be in the room below you trying to sleep. Maybe have some extra chairs and beer for the guests from adjacent rooms. JJK Quote Link to comment Share on other sites More sharing options...
BE36 Posted March 12, 2010 Share Posted March 12, 2010 Seal the back like 60th aniversary and the false corner would not be required - From your description they are close enough to the back wall for this to work well. There are a pair of 60th K-Horns at the local dealer, we kept pulling them further and further away from the wall one night for fun. We had them almost 25cm from the wall before there was any bass real output drop. Quote Link to comment Share on other sites More sharing options...
Timmikid Posted March 13, 2010 Author Share Posted March 13, 2010 Ok. Thanks all! Food for thought. It's not rental btw and yes the neighbors might benefit . First I will stare at the speakers and think about the possibilities, then I will translate Garyc into the metric system. [8-|] There is no way the speakers can fit snug onto the back wall as they are now, It is sloping. I will take pics. Thanks again, Tim. Quote Link to comment Share on other sites More sharing options...
BE36 Posted March 13, 2010 Share Posted March 13, 2010 Picture of a sealed back on a K-Horn can be seen at this Link: http://www.klipsch.com/na-en/products/60th-anniversary-klipschorn-overview/ "For the first time ever, the rear of the speaker has received a cosmetic, and functional "facelift." Solid panels now enclose the rear high frequency and low frequency cabinets to add a more elegant appearance, eliminate any corner and response issues and for the first time in the Klipschorns history allow for toe in or out." Quote Link to comment Share on other sites More sharing options...
theplummer Posted March 14, 2010 Share Posted March 14, 2010 the back wall starts to tilt inwards, because the pointed roof starts there. So... My Khorns are snug/sealed to the side walls, but at the back there is an opening. Snug at the top, but a serious few inches of space at the bottom. Are only the top hats touching the corner of the wall? If so take the wingnuts loose that hold them on and slide the base cabinet tight to the corner and let the top hat stick out the front for a few inches. If that works, you could just remove the top wooden panel from the tophat (you know the one that looks like home plate) Quote Link to comment Share on other sites More sharing options...
artto Posted March 14, 2010 Share Posted March 14, 2010 Seal the back like 60th aniversary and the false corner would not be required - From your description they are close enough to the back wall for this to work well. There are a pair of 60th K-Horns at the local dealer, we kept pulling them further and further away from the wall one night for fun. We had them almost 25cm from the wall before there was any bass real output drop. Contrary to popular belief a gap or loss of seal on the corner/back/edges of the Khorn affects the mid to upper bass more than the lower frequencies. See Klipsch Dope From Hope newsletter Vol. 2, No.12 Quote Link to comment Share on other sites More sharing options...
Timmikid Posted April 3, 2010 Author Share Posted April 3, 2010 Thanks all. Are there more threads/pics of Khorns that have been closed at the back? Any tips on this mod? Quote Link to comment Share on other sites More sharing options...
Marvel Posted April 3, 2010 Share Posted April 3, 2010 Greg did an extensive restoration on a pair of khorns, enclosing the back along the way. The whole process is detailed on his website. http://www.voltiaudio.com/flkhorn.shtml Quote Link to comment Share on other sites More sharing options...
Timmikid Posted April 5, 2010 Author Share Posted April 5, 2010 Wow. Thanks! Quote Link to comment Share on other sites More sharing options...
seti Posted April 5, 2010 Share Posted April 5, 2010 How about some pics of the khorns in their new home : ) Quote Link to comment Share on other sites More sharing options...
BE36 Posted April 6, 2010 Share Posted April 6, 2010 I would like to read that Dope From Hope article and thier definition of Mid and Upper Bass. Stereophile defines Mid Bass from 40 Hz to 80 Hz. Upper Bass 80 - 160 Hz. Is there a link to all the Dope from Hope articles? Quote Link to comment Share on other sites More sharing options...
DrWho Posted April 7, 2010 Share Posted April 7, 2010 Stereophile defines Mid Bass from 40 Hz to 80 Hz. Upper Bass 80 - 160 Hz. You sure about that? That is most definitely not the language that everyone else in the industry uses... Quote Link to comment Share on other sites More sharing options...
Timmikid Posted April 7, 2010 Author Share Posted April 7, 2010 How about some pics of the khorns in their new home : ) Coming soon in this theater! [Y] Quote Link to comment Share on other sites More sharing options...
garyrc Posted April 7, 2010 Share Posted April 7, 2010 Stereophile defines Mid Bass from 40 Hz to 80 Hz. Upper Bass 80 - 160 Hz. You sure about that? That is most definitely not the language that everyone else in the industry uses... I remember a article in Stereo Review in the '70s that called 100 -- 200 Upper Bass, 50 to 99 Mid Bass, and below 50 Deep Bass. It was in reference to the effect of equalizer sliders. These ranges match my own use, except I would think of 200 as being more like lower midrange. Although the piano goes down to 29.5, the pipe organ to 32 (16 for some theater organs like the pipe that caused the people at the old Fox theater in San Francisco to put a net up, just below the ceiling, to catch the plaster that fell off whenever that pipe sounded), classical and jazz scores rarely call for instrumentalists to play below about 32 Hz. Movies, with the infernal Bass Machine, are an exception. Khorns, sealed in corners, in a large room, are pretty clean, if somewhat attenuated, to 32. Quote Link to comment Share on other sites More sharing options...
seti Posted April 7, 2010 Share Posted April 7, 2010 How about some pics of the khorns in their new home : ) Coming soon in this theater! Congrats on scoring khorns in the Netherlands. How did you manage that? Quote Link to comment Share on other sites More sharing options...
BE36 Posted April 7, 2010 Share Posted April 7, 2010 http://www.stereophile.com/reference/50/index5.html Really sure - Gordon Holt. See link above. midbass The range of frequencies from 40-80Hz. Quote Link to comment Share on other sites More sharing options...
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