Jax Posted May 29, 2003 Share Posted May 29, 2003 I LOVE the sound of my LaScala's at home, but would like to tame the rather harsh highs on my Vintage (E-Crossover) Heresy's in my work system. I've been going back through some of the extensive posts on modifying vintage Heresy's to tone down some of their brightness. I've come across some good suggestions including lowering the tweeter attenuation by swapping over the lead on the 2 tap to the 3 tap of the Squaker. Also changing the rear panel to MDF. Criticicism seems to focus also on the lack of bass, the limiting factor being the size of the box. Has anyone tried removing the horns from the box entirely? This would mimic in some ways what the LaScala, Khorns and Belles do by putting the sqwaker and tweeter in an open-backed section above the woofer encloser. Is there any reason the horns would even need a box (enclosure) at all? It seems to do this you would just need to seal off the holes in the Heresy box with an additional piece of 3/4" MDF or Plywood screwed in from the inside. The crossover itself could be removed leaving only the woofer in the box. I wasn't able to find anyone who mentioned this possible solution. Is there something I'm missing that would completely throw things out of balance in doing this, or is it a worthwhile solution? Advice from any of you experts would be much appreciated. Quote Link to comment Share on other sites More sharing options...
Stovebolt6 Posted May 30, 2003 Share Posted May 30, 2003 Removing the horns from the box would have the effect of increasing the internal volume of the box. In a sealed box system like the Heresy the air inside the box acts as a spring. Changing the volume of the box changes the compliance of the air spring. Springs have a resonant frequency based on the rate of the spring and the mass it is supporting. The larger the box, the softer the air spring, the lower the resonant frequency. This all sounds good but remember that the air inside the box is part of the drivers suspension. The other part of that suspension is the suround, spider and the motor. The system is tuned to deliver a flat frequency response. Increasing the internal volume of the box will lower the resonant frequency of the box but may cause a dip in the frequency repsonse and hurt overall performance. There are many shareware programs available that will let you model senarios with different drivers and different box sizes. You will need to know the Theil and Small parameters(T/S)of the driver you are playing with. Do a search for those on this fourum and you will most likely find them for the Heresy's Woofer. Do a search for "Speaker Design Software" on the net and you will find a few shareware downloads. Plug the parameters into the software and it will show you the effect your changes will have on the system. Good luck and be carefull. Going down this path can be very addicting! You won't realize you are hooked until you own a table saw, a router and everything in your house is covered in sawdust! Quote Link to comment Share on other sites More sharing options...
Jax Posted May 30, 2003 Author Share Posted May 30, 2003 Thanks for the clarification Stovebolt6. Too late for the warning though, I already have a table saw and complete array of woodworking tools. I get the principal you are describing about increasing the volume in the box. Would an increase of such a small degree as removing the two horns and crossover have that much of an effect? I don't think they take up more than 15% of the total volume in there. The second part of the question that you didn't address is, do the horns themselves need any kind of enclosure at all around them? They don't seem to be dependent up on the internal pressures as their drivers are entirely enclosed and the horn shells are certainly not effected by such small amounts of pressure. Am I wrong in assuming this? So by the same token would the Squawker and tweeter sound identical if you were to remove them from the box and, say, bolt them to a stand, or attach them to a facing similar to the facing of the actual speaker just supported in space with no enclosure? Independent of the question regarding the woofer and the box, would the horns change significantly outside of the box? I wonder this because many of the horn speakers I see, including my own LaScala's, have the horns in an 'open' enclosure or no enclosure at all sometimes (such as the AvantGarde's & Calix). Quote Link to comment Share on other sites More sharing options...
Stovebolt6 Posted May 30, 2003 Share Posted May 30, 2003 The horns do not need the box. Outside, they will not be subjected to the vibrations of the LF driver. Just noticed your signature... ... does the dynamat help? Quote Link to comment Share on other sites More sharing options...
Jax Posted May 30, 2003 Author Share Posted May 30, 2003 Just noticed your signature... ... does the dynamat help? The previous owner of my 77' LaScala's applied the Dynamat to the horns there so I have never actually been able to do a side-by-side comparison. Going to the DH Lab silver wire for the internal wiring DID help imaging and focus and overall sound stage (going from the stock wires). I applied the Dynamat to the horns in the Heresy's, but also lined the cabinet with "Black Hole" at the same time I did the horns. The result of both mods was a more forward, more harsh midrange and highs (maybe as a result of a dampening of the lows). In other words NOT GOOD. My thoughts, based upon other posts here as well as talking to a few friends, is that it is more a result of the Black Hole material which covers the entire back panel and top of the cabinet. The lows no longer seem to have any snap or punch if you will and it has thrown everything out of balance. As far as applying Dynamat to the horns; I can't say for sure, but I do think they likely would yield an improvement on the older metal horns (like mine - both Heresy's and LaScala's are K55V's), albeit less pronounced than on the larger horns of the LaScala's (and Belles, Khorns and Cornwalls as well). I think the idea of dapening the cabinet was a mistake in the case of the Heresys. Easily corrected fortunately as the adhesive is not as strong as Dynamat. The previous (original) owner of my LaScala's also had Khorns which he'd treated the horns with Dynamat and did say it was an noticeable improvement on both speakers. I don't really know him well, but he had some very nice gear that was thoughtfully chosen and well setup and sounded great together (for whatever that is worth). Thanks again for your input! Quote Link to comment Share on other sites More sharing options...
formica Posted June 2, 2003 Share Posted June 2, 2003 ---------------- On 5/30/2003 6:03:32 PM Jax wrote: Would an increase of such a small degree as removing the two horns and crossover have that much of an effect? I don't think they take up more than 15% of the total volume in there. ---------------- Actually based on the TS parameters of the K-22 Heresy woofer, the box is undersized and therefore features a high cabinet Q over 0.7 ... check this link: http://forums.klipsch.com/idealbb/view.asp?topicID=9689 So no harm done in increasing it by 15% or more. Rob Quote Link to comment Share on other sites More sharing options...
dodger Posted June 2, 2003 Share Posted June 2, 2003 Greetings: I modified my Heresys. The effect was a noticeable improvement in mids, voices, guitar. I did one first and a/bed them and 10 out of 10 people that did not know of the mods chose the modified. My mods: 1 x 2 bracing, cut to fit, around all the center of the four inside walls of the box. I used liquid nails to attach. Wrapping the exterior of the mid and tweeter horns (not the drivers) with Dynamat . Applying the Dynamat to the inside walls and the back of the cabinet. Putting acoustic fibre-fill (1.5 packages into the cabinet before closing it back up. I did notice some loss of sensitivity. But take a voice like Streisand or one like Joplin - Janis, There was an improvement. Violins, acoustic guitars, and bass definition also improved to me. The wood braces eliminated the "hollow sound" of the cabinet as did the Dynamat . The Dynamat to the metal horns toned down the ringing effect and some harshness. The fiber-fill, I'm not sure. All of the above did add weight to the speaker but brought down the brightness that led to listening fatigue. Win Quote Link to comment Share on other sites More sharing options...
Jax Posted June 2, 2003 Author Share Posted June 2, 2003 ---------------- On 6/2/2003 3:42:43 PM formica wrote: ---------------- On 5/30/2003 6:03:32 PM Jax wrote: Would an increase of such a small degree as removing the two horns and crossover have that much of an effect? I don't think they take up more than 15% of the total volume in there. ---------------- Actually based on the TS parameters of the K-22 Heresy woofer, the box is undersized and therefore features a high cabinet Q over 0.7 ... check this link: http://forums.klipsch.com/idealbb/view.asp?topicID=9689 So no harm done in increasing it by 15% or more. Rob ---------------- Thanks for the input Rob. I thought I would share some of my experiments I completed this weekend with the forum as it may be useful knowledge for future tweakers of Heresy's. Actually there is an excellent thread from a few years back started by Klipschguy in which there are many useful comments including the tweak on which the thread began, which I've found to be an excellant recommendation. You may find that thread here: http://forums.klipsch.com/idealbb/view.asp?topicID=14558 The same solution is also suggested in a later thread by John Albright. Since I actually tried out a few different things which ultimately did not work I would like to share those attempts here so that others may learn from my mistakes. The first thing I did was outlined in a previous post to this thread. To recap; my first tweaks were to cover the horns in Dynamat (my LaScala metal horns are treated this way and do not sound harsh or bright at all). This is a very easy tweak. It has been debated here as far as the Heresy horns are concerned since they are much smaller than the horns in the rest of the Heritage series. I could still get the Hersy horn body to ring in spite of it's size and, of course could not with the Dynamat applied. Unfortunately this tweak corresponded with some serious dampening of the interior of the cabinet as well so I really wasn't able to evaluate it directly. I'm too impatient and have got to keep reminding myself to change ONE THING AT A TIME!! Anyway, I think the cabinet dampening (Black Hole) really took the steam out of the woofer and consequently made the mids and highs stand out even more so that the speakers sounded way out of balance with no punch to the lows anymore (not that they had a lot to begin with). While I had the boxes open I had also applied a bead of re-useable window caulking material around the borders of both horns to better seal the cabinet. After considering the alternatives I tried my theory that began this thread of removing the horns from the box. Alas, I have a tablesaw and was obsessed at this point and had a spare bit of birchply, so I built two L-shaped brackets out of 3/4 inch birchply and cut the facings out to match the horn openings in the Heresy facing. I removed both horns and crossover from the box and attached them to the new exterior L-bracket made to sit neatly on top of the speaker cabinet. I cut an additional piece of 3/4 inch birchply to screw on the interior of the cabinet and seal the two holes left by the absent horns. I rewired the woofer to come through the back of the cabinet via the binding posts, and ran a second set of wires to the woofer terminals on the crossover (E type). The speaker wires were wired directly to the crossover as they are on a LaScala. In fact, the set up mimics the LaScala in miniature though in the LaScala the horns are surrounded on five sides with an open back. The results: Terrible! Harsher and brighter than ever. Reminds me of how horn-Naysayers describe the sound of horns; like someone cupping their hands and shouting at you. I know just how GREAT horns can sound so I wasn't about to stop there. Back to the drawing board. I tried the suggestion that Klipschguy makes on the thread I referenced, as well as John Albright in a later thread: unsolder the wire from the #3 tap on the T2A and attach it to the Squawker's negative lead which is the #2 tap. This lowers the tweeter's output by 3db. In my exterior horn configuration I could hear an improvement, but I still felt the bass was suffering. I don't know why this is as removing the horns and crossover only give the woofer about 10-15% more volume in the cabinet. Perhas someone more knowledgeable than me can speculate. Even a non-audiophile friend who'd heard my system before commented on how poorly it sounded with the horns out of the cabinet, so it was not a subtle difference. OK, so back in the cabinet go the horns. This time I replace the back panel with 3/4 inch MDF and replace the terminals with some slightly better ones I bought at Speaker Lab. Instead of the messy window putty around the horns I decided to try some strips of foam adhesive strips for sealing windows and doors. I used a combination of the 3/8 as well as some 3/4 inch widths. I outlined the boarders of the horns with the foam strips and screwed down the speakers which flatten the foam almost entirely and create a pretty good seal as far as I can tell. I also did that all around the rear framing that the back panel screws into to create a similar seal with the back panel. I left the crossover modified as described (#3 tap to #2tap). Viola!!! Brilliant!! Smoother than ever with a sound close to what I'd imagine a mini-LaScala would sound like. No more harsh mids and highs (non-fatiguing, which was the goal when I started out). Bass had it's snap back, the music flowed effortlessly with no glaring inbalance. Better than I started, but I could have saved much time and effort by heeding much of the advice given on the threads I already mentioned. I had also decided that my Heresy's sound much better to my ears when they are elevated off the floor. I'd experimented with cinder blocks and found that 16 inches worked really well for me. I built to 16 inch tall boxes made of , you guessed it, 3/4 inch birchply. I put some hefty handles on either side and reinforced all thecorners and thebottoms of the boxes and filled each with about 100 lbs of play sand. I floated a lid on top of the and and placed the Heresy's on three cones on top of the lid. These stands are affectionately known as "The Widowmakers". It is best to find the exact spot on the floor that you will want your speakers using the cinder blocks first, then place the sandboxes in place and fill them. You are not going to want to move them around much, or any great distance unless you already have children and or didn't want any(more). They work great and make a definitive improvement over the cinder blocks in the definition and focus of the soundstage. So, If anyone would like to try the horns outside the cabinet themselves I still have the nicely built L-brackets that would hold them on top of the speaker. I'd send them for free to anyone who wants to experiment...just pay the postage. Perhaps there are other ways to work it with them outside...perhaps reducing further the volume of the woofer cabinet...I'm no engineer...just a hopelessly addicted audiophile and tweaker. I do love the way they sound now that I've worked it all out. The Heresy's are in my work system which is entirely different than the one listed in my sig file below. The rest of the work system is: Quicksilver Mini-Mite amps with vintage Tesla EL34's and Tungsram 12AX7's ARC LS2B Modified by Great Northern Sound with Siemens E88CCa Sonic Frontiers SLP-1 with GEC 12AT7's and Mullard E88CC's Rega Planet 2000 AR Turntable with various Merril Mods, Linn ITTOK, Homemade Power Supply Sansui TU-717 Tuner Cables by Stealth, DH Lab & Music Metre PowerWedge 114 I am not as critical of this system as I am of my home system since I am not sitting and listening to this one, but rather working to it all day. The Quicksilver amps are a wonderful match with any of the Klipsch Heritage speakers in my experience. I reallly appreciate what Mike Sanders puts into his products.....like the vintage Klipsch gear you get a big bang for your buck. Quote Link to comment Share on other sites More sharing options...
efzauner Posted June 2, 2003 Share Posted June 2, 2003 Hello all Dont touch that SAW yet! First, the heresy box is about 52 liters. Removing the mid and tweeter may add a few liters to it. (compare the volume of the mid horn to a one quart milk carton, it may use up the space of a few milk cartons, but not that much more). Increasing the internal volume by 5 liters to 57 liters has a negligible effect on the low end. It is not worth the effort at all! What you could do is add a port to the rear: Remove the existing back, and cut a new one the same size, and cut a hole for a port (you can buy the nice plastic tubes at most electronics/speaker stores. Use a 3inch diameter port that is 3 inches long. This port will be tuned to 44 Hz. There is a 2-3 dB hump in the bass responce that may make it sound a bit boomy. At the same time you can add a nice terminal block with screw or banana connectors. You can experiment with different length tubes. Vary by no more than 1/2 shorter or longer. Best thing is you can go back to original by putting the original back back on. Or simply seal the port to listen to classical music when you do not want the extra bass of the port.. Better yet, get winISD demo for free and try it yourself. the T/S parameters for the Heresy can be found if you search for k22 in the forums. They have been posted by a Klipsch technician as for adding a stifener, and dynamat (expesive stuff and impossible to remove) or plumbers putty (cheap and reversible) are all fine and easy things you can do too. Adding the port will have the bigest effect and is rather easy and cheap. Edmond Montreal PS: I own a pair of heresies with a rear vent. The vent is 2 1/4 inches long. Try different ones! Quote Link to comment Share on other sites More sharing options...
Jax Posted June 2, 2003 Author Share Posted June 2, 2003 ---------------- On 6/2/2003 6:48:51 PM efzauner wrote: Hello all Dont touch that SAW yet! First, the heresy box is about 52 liters. Removing the mid and tweeter may add a few liters Just to clarify a few things I'm not by any means suggesting anyone get out their saws either. I posted my results exactly to discourage the same. Although the MDF backing and sealing same I think does make an improvement over the plywood back. MDF is CHEAP too. On 6/2/2003 6:48:51 PM efzauner wrote: as for adding a stifener, and dynamat (expesive stuff and impossible to remove) or plumbers putty (cheap and reversible) are all fine and easy things you can do too. I should add here that I've been using the Dynamat as a catch-phrase for that type of material. I actually used a very similar dampening material from Parts Express: http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=268-030 Montreal It is VERY easy to work with a heat gun and a small roller. It is as tenacious and conforming as Dynamat and ends up looking and feeling identical to my Dynamat treated horns on my LaScala's (they actually DO have Dynamat on them). The PartsExpress material is about $3.70/sheet and it took three sheets to treat both Heresy speakers, so it is by no means expensive. Best, Marco Quote Link to comment Share on other sites More sharing options...
Invidiosulus Posted June 3, 2003 Share Posted June 3, 2003 I posted a while back that I thought it was odd that the backs on my 1981 heresy's were only a 1/2" piece of plywood when the rest of the cabinet used 3/4". I ended up cutting a piece of 3/4" MDF the same size as the back of the heresy's and putting it on the outside of the existing back. I just used longer screws then the stock ones and sandwiched some weather stripping between the MDF and the plywood back. Overall I think that this helped to clean up the bass a little bit as before I did the mod the 1/2" back panel would resonate at high volumes. Now with what is essentially a 1.25" back piece there is not much extraneous resonance at all. Peace, Josh Quote Link to comment Share on other sites More sharing options...
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