Bill W

Tommy, Tell us more about your room- What is the LxWxH? are the corners usable for K-horns? Which wall will they be placed against? This information is important for estimating the quality of the sound you can expect. Even if your situation is less than ideal, it may be ok if this isn't a permanent arrangement. (I lived with my first set of K-horns for four semesters in the dorms at college- It was worth the wait for me!) Good luck, Bill

Hi Al- Considering the age of the speaker it is a good idea to inspect the woofer for damage. My first pair of K-horns were of similar vintage as yours (about 25 years old when I got them in the mid 70s.) The woofers were Stephens Trusonic - rugged and well-built however they were badly deteriorated along the surround portion of the cone with numerous cracks and tears. This condition will kill the bass performance! If your woofer is original it will likely be a Stephens 103LX2 or an Electo-Voice EV 15 WK. There are a few more things to keep in mind: 50s era woofers were LOW COMPLIANCE- they were very stiff. The surround was generally made from the same material as the cone and was prone to deterioration from many years of use. The current production woofer K-33-E has been used for over 25 years and easily outperforms the older units used in K-horns of the 50s and 60s. Your Klipsch bass horn uses a removable woofer mounting board inside the back air chamber. It is secured to the throat section of the horn on each side by two angle iron brackets held in place by wingnuts on studs. The motor board that the woofer is mounted on was changed in the early 60s from a slotted opening of 6" to one of 3". This was done to improve the frequency response above 250hz. This modification makes the woofer less sensitive to losses when the speaker doesn't fit tightly into the corner. If your goal is to preserve the speaker in its original condition, the woofer can be reconed if needed, otherwise the current driver can be purchased new from Klipsch. When reinstalling the woofer in the back air chamber, it is very important to avoid air leaks between the motor board and the horn throat. Be sure to inspect the gasket carefully and tighten the wingnuts properly. Please let us know what you find inside! We will try to help with any questions you may have. Good luck, Bill

I have experimented with this on several Heritage models over the years "just to see" if the difference was audible. The answer is yes - the degree depending on the program material. I personally don't hear the difference in the bandwidth of the midrange/tweeter crossover on Klipschorns probably because it is narrow (18db/octave). It is quite apparent to me in the much wider region of woofer/midrange crossover because of the more gradual 6db/octave crossover between these drivers. What you hear is some loss of output in the octave centered around 400 hz. Interestingly, PWK published a letter to dealers in the mid 1970s stating that after many frequency response measurements of the Heresy, it was decided to reverse the polarity of the midrange and tweeter relative to the woofer in future production runs to improve the frequency response of that model. It instructed dealers to make the change to all Heresys they had in stock at the time as well! I can tell you that on the Heresy, this change is plainly audible, although it is the only Heritage series speaker to have this change done to my knowledge. Hope that helps- Bill

MacKlipsch- I'm still looking for a Belle Klipsch for center channel. I would be happy to buy a pair and split with someone else on this board. If you see any, let me know! Thanks, Bill W.

Hi Al, You ARE planning on creating a version for the HERESY aren't you??? (Just thought I'd mention it before you entertain any thoughts of heading for your Lazyboy recliner!!!) Thanks, Bill W.

Dear filmofreddy, Thanks for your reply-I remember discovering the differences in polar patterns between the K-5 and K-400 horns on A-B comparisons. While "playing" with these horns, I took them outside to avoid the influence of the reflected sound indoors. I suspected that some of the weirdness you describe with the K-5 at frequencies above 3000hz was due to reflections of the emerging wavefront off the top and bottom insides of the upper cabinet where the off-axis portion of the radial-shaped mouth empties into the upper cabinet. I removed the top portion of the cabinet and it made a distinct difference.As a further experiment, I raised the K-5 horn and driver about 6" above its stock location to avoid possibility of reflections from the bottom of the upper cabinet. When an A-B test was conducted between this configuration and the unmodified speaker, the differences were even more obvious especially indoors. My recollections of the sonic differences between the K-5 and K-400 horns are that the "shrouding" of the K-5 by the upper cabinet may have accounted for some of this difference. Regarding your comments on vertical mounting of the T-35A, I made this modification on the new top end by fabricating brackets to attach the tweeter to the inside of the K-400 horn mouth. While it did improve the HF radiation pattern over the horizontal plane, I was concerned about the interference created with the presence of the tweeter in the much smaller mouth of the K-400. Concluding that the off-axis performance was of less importance with corner speaker placement, I restored the tweeters to their stock location. Center channel applications with Lascalas or Belles would probably benefit more with a wider horizontal dispersion pattern, especially in wide-stage rooms. Thanks again for all of your great posts! Sincerely, Bill Walko

Dear filmofreddy, Thanks for your reply-I remember discovering the differences in polar patterns between the K-5 and K-400 horns on A-B comparisons. While "playing" with these horns, I took them outside to avoid the influence of the reflected sound indoors. I suspected that some of the weirdness you describe with the K-5 at frequencies above 3000hz was due to reflections of the emerging wavefront off the top and bottom insides of the upper cabinet where the off-axis portion of the radial-shaped mouth empties into the upper cabinet. I removed the top portion of the cabinet and it made a distinct difference.As a further experiment, I raised the K-5 horn and driver about 6" above its stock location to avoid possibility of reflections from the bottom of the upper cabinet. When an A-B test was conducted between this configuration and the unmodified speaker, the differences were even more obvious especially indoors. My recollections of the sonic differences between the K-5 and K-400 horns are that the "shrouding" of the K-5 by the upper cabinet may have accounted for some of this difference. Regarding your comments on vertical mounting of the T-35A, I made this modification on the new top end by fabricating brackets to attach the tweeter to the inside of the K-400 horn mouth. While it did improve the HF radiation pattern over the horizontal plane, I was concerned about the interference created with the presence of the tweeter in the much smaller mouth of the K-400. Concluding that the off-axis performance was of less importance with corner speaker placement, I restored the tweeters to their stock location. Center channel applications with Lascalas or Belles would probably benefit more with a wider horizontal dispertion pattern, especially in wide-stage rooms. Thanks again for all of your great posts! Sincerely, Bill Walko

Dear Ed O. In all the discussion about the K-400 horn nobody has answered your very perceptive question regarding the relationship between horn throat diameter and smoothness of freqency response. I think it's a great question. Back in the mid 70's I had an old 50's pair of K-horns at college with the K-5 midrange horns and K-55-V drivers. These horns had a 1" throat as opposed to the 0.7" throat of the K-400,as well as a more rapid flare rate. When I bought all new components from the factory to update the speakers,I had an opportunity to compare and contrast old and new parts systematically. The old K-5 horn with a new K-55-V driver and AA crossover was not as smooth as the new K-400 horn with identical driver and crossover.The range on the K-5 was more limited(crossover points of 500hz-5000hz). There are other factors which are involved here: The K-5 was made of fiberglas with an open-faced mouth while the K-400 is cast aluminum and requires flange mounting. I do remember being surprised that there wasn't nearly as much difference between the two horns as I anticipated when other variables were eliminated. I have always been curious to know how freqency response curves compare between various compression drivers when coupled to the appropriate horns vs. the actual driver output. Where are most freqency response anomolies introduced? Perhaps FilmoFreddy can weigh in with his extensive knowledge. I do wish I still had those K-5 horns,they were marvelous works of audio art!!!