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BeFuddledinMn

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Everything posted by BeFuddledinMn

  1. It looks and sounds as if the new Cornwall IV is a major improvement. A couple of thoughts come to mind: First, given the relatively high distortion generated by tuned port vs. horn loaded bass in the lower end, it’s curious that the cross to midrange is still kept relatively high in the new Cornwall IV. As an owner of Cornwall I’s with solder lug K-55’s and B2 crossover design, it would be interesting first and foremost to see a distortion comparison between the two from say 30hz to 800hz. Second, does the introduction of the new mumps tractrix midrange on the Cornwall IV in addition to the Forte III, implicitly confirm the obsolescence of the k-400 to k-700 series of exponential horns? Lastly, given the new bass porting and midrange horn, is the new Cornwall IV now getting close to, or better than, the Lascala and Klipschorn in midrange clarity, and significantly closer to their bass distortion performance? Paul Klipsch used to market the smaller Heritage speakers as 2/3 Klipschorn. Are we now being offered, say, 8/10th’s at half the price? Looks like another great job by Roy and the Klipsch organization.
  2. Interesting update on the new Klipshorn and i’ll look forward to seeing the curves. For now, I’ll only say this, the Klipschorn is perhaps the most difficult speaker to measure and after having done extensive Klipschorn testing in the past, I’m not worried in the least. 😉
  3. Hello. Your question is complicated by the fact that you’re talking about Georgians rather than Klipschorns. Having said that, I can share a few points. First, those EV 15wk woofers were originally 4ohm, not 16ohm. Second, reconing these is extremely problematic as far as replicating original performance. Third, yes there is a performance difference between these early Alnico magnet monsters vs. say today’s klipsch k-33e, or the Crises cast woofer. (Yes, I’ve tested them all) the good news, bad news is this: you can successfully utilize a Crites cast woofer with a 6x13 slot, or 3x13 throat slot on the Klipschorns and Georgians. The bad news - particularly with the Georgian, is that you will need to address two crossover issues - first the reverse polarity utilized in the stock Georgian may be problematic with the Crites woofer in that application - and phasing is critical with those speakers. Second, the woofer inductor values will also need significant adjustment to approximate the original EV woofer performance and proper crossover point to the next driver. Easiest path in my opinion is to simply install those correct 4ohm woofers you have - if there are no cone issues, and if so, those 60 year old woofers will perform spectacularly. Second path would be to purchase two original EV 15wk woofers in excellent condition on eBay, and put your originals aside if they have cone issues. I would only move to an alternative woofer such as the Crites in this situation, if you have the willingness and ability to spend on crossover work and extensive testing to produce the proper handoff from the woofer and “midrange.” Hope that helps.
  4. Just stumbled upon this golden nugget of a topic from way back and thought I’d add my recent findings on the topic - about 16 years late, lol. Here are some relevant woofer/motorboard test results from my efforts last year:
  5. For what it’s worth, I did a lot of inductor testing on the Klipschorn a few months back (see my Klipschorn woofer & motorboard comparison post) and I can tell you that there are measuraeable differences. Whether anyone can hear theses differences is another matter. Clearly, large changes in inductor value ( of any inductor type) do make real differences both to the ear and in measurements. Of course, in the Klipschorn, these changes really require corresponding changes in the midrange network and integration as well in order to ensure any potential real “improvement.” Your individual room acoustics will have a real impact on this as well. -BefuddledInMn
  6. Not surprising that Mark Levinson chose the Klipschorn. PWK had it right with sensitivity, distortion and dynamic range. Outstanding contribution here from Garyc - and spot on. Owning Klipschorns, Lascalas, Cornwalls and Forte II’s, Klipschorns win hands down IMHO. However, after years of listening and measuring, it’s pretty clear that the average home Klipschorn installation is a million miles from the anechoic perfection achieved by Klipsch at the factory. IMO, the advent of Audyssey like capabilities finally present an opportunity to address that. In fact, I’ve wondered for some time why Klipsch hasn’t produced a proprietary Klipschorn “Audyssey” capability that would literally take the Klipschorn to the next level - in each home. A built-in menu of curves? Why not? In my opinion, any other tinkering is nonsense in comparison. Is anyone at Klipsch listening?
  7. Perhaps djk can give us more perspective on this driver. I always believed it was the original k-55 incarnation - a first rough design. Mine has absolutely no manufacturers identifiers, and the Klipsch label is hand etched with letters and numbers, barely discernible. I own early University SAHF drivers and the design of the threaded side doesn’t match the casting characteristics at all. That and the lack of identifiers always led me to believe these were a custom collaborative design for Klipsch under contract. For what it’s worth, I’ve always thought it was the ugliest mid range driver ever produced, but don’t let the coffee can look fool you, these are really HEAVEY!
  8. I found one of these drivers on a 1950’s Klipschorn years ago. I promptly removed it in favor of a modern K-55, but I’ve kept it in my Klipsch parts collection. You don’t see them turn up very often. Here’s a few pics of it, showing both sides.
  9. For what it's worth, I've built several Cornwall or Cornscala cabinets out of Baltic birch and I wouldn't even think of using anything else. The consistency of thickness, veneer, void free, etc are all far superior. And the density....lift a piece of Baltic birch, then a piece of the best standard plywood and you'll notice the huge weight difference. Of course, Baltic birch requires sharp carbide tools and a slower pace due to this. In production settings, this difference needs to be incorporated into the techniques, etc., but for hobbyist work, that's not a big problem for a huge reward. In addition, like others have pointed out, it's getting REALLY hard to find traditional plywood that is worth using anymore - with deteriorating quality hat creates huge waste, frustration and higher total costs.
  10. It's the middle of summer, but I thought I'd throw a couple more thoughts on this topic: Given what appears to be an organic challenge of the Klipschorn design, it would be interesting to hear from Roy Delgado on the balancing act between folded horn woofer polarity, midrange horn type, crossover point and room factors (vs. factory anechoic chamber). In practical terms, as long as I can remember, the biggest knock on the Klipschorn after effective corners, was that in many rooms, the Klipschorn just didn't "work." Of course, the reasons are many and some even amusing, but optimization of the Klipschorn "in the field", is nonetheless a perennial topic and the expectations of someone who drops $15k on a new set of speakers are understandably high. PWK never allowed for user controls in his speakers because he (correctly in my opinion), knew that until recently, it would be nearly impossible for most consumers to objectively measure/and or evaluate user settings. However, with the hardware/software tools now readily available for in home sound customization, it would be interesting to ponder the usefulness and viability of a future Klipschorn feature that offered a Klipsch designed hardware/software based optimization kit in conjunction with an advanced, variable setting crossover - providing a direct Klipsch based hardware approach to user optimization, vs. say an Audessy based approach. Risks? Efficacy? Cost? Of course, that might be considered a new version of heresy and it will inevitably beg the question as to whether this is a problem in search of a solution, or a solution in search of a problem. -BefuddledInMn
  11. Interesting discussion. I'm a huge PWK fan myself, but I for one wish Klipsch would take a new crack at the top section of he Klipschorn. Yes, there are pros and cons to that, but just my personal feeling. Meanwhile, many of us, including myself have no problem using alternatives produced by Roberts and others. However, in my experience, integrating a midrange horn/driver change for real improvement to a Klipschorn, both measured and heard, is not as simple or easy as it looks. While I do own Volti midrange horns, have measured, listened and custom integrated those successfully to the Klipschorn, (I have a thread "Klipschorn Woofer polarity challenge" touching on this in the technical section), I have never owned Volti speakers, nor measured or listened to them to give an opinion on performance efficacy. For that matter, I've never taken the Volti "drop in" complete Klipschorn "upgrade" package for a test run either. In any event, I have always respected and valued invention, while admiring any and all efforts toward real improvement. As an aside, I've owned a lot of speakers including presently most Klipsch heritage models - and I'll go with the Klipschorn everyday of the week. However, as we all know, they do present some challenges, and consequently, I'm not surprised at the direction Volti went.
  12. OP: I've done extensive testing of the Volti horn with the B&C DCM driver - compared to the k400/k55 and the Klipsch K5J/K55, with numerous crossovers including ALK universal, etc. You can search for my thread "comparing vintage Klipschorn woofers, midrange, etc., in the technical section. You can review the measurements and comparisons I've made there, but in my opinion, the Volti horn, properly integrated with the right crossover, is an upgrade to the stock k400/401 which is often identified as the biggest issue with the Klipschorn. Some will prefer the Klipsch house sound with the k400, but there is a reason that after all these years, Klipsch refined the midrange crossover down to 4500hz. I will I'll also add this: there is a lot going on with the Klipschorn when it comes to proper woofer/bass horn integration and crossover to a particular midrange horn - and achieving real improvements is a bit more complex than simply dropping in a different mid horn, driver, etc. Having said that, I would agree with most that even the simple "drop in" of the Volti midrange horn offers the Klipschorn a more listenable sound at a minimum. FWIW, I wouldn't shy away from a pair of Klipschorns with Volti horns. -BeFuddledInMn
  13. WMcD, I've always appreciated your contributions and this is no exception. (And I rarely have the time to get on here either) Based on my own experience I can't disagree with anything you've said. Measuring Klipschorn performance is a real headache in the home for all the reasons you've mentioned and then some, so after doing separate measurement positions per driver, I try to measure the whole package at the distance and level that I would typically listen - believing that this best reflects what a listener's ears will hear. Having said that, about a month ago I asked a very knowledgeable colleague who has 50 years of Klipsch experience and professional measurement equipment and measuring experience to investigate my observations with his own tests. He reported woofer polarity results similar to my own. Your point on differences between the Georgian and Klipschorn are valid of course and I was simply drawing attention to the common challenge with folded bass horns - even though, as you correctly suggest in my opinion, there may be different solution paths with each. Admittedly, I may have leaned a bit into the wind here to stir the discussion, but my aim here has been to get all the knowledge and perspective we can out on the table on an issue that seems seldom noted and even less understood. More importantly, I believe you've identified and described one of the key variables in determining the "correct" polarity choice - the midrange horn used - and the point at which it's crossed. In fact your discussion is confirmed by the testing I've done with three different midrange horns in combination with three different woofers and two different motorboard slots, etc. In short, my testing has shown that the woofer polarity choice largely depends upon which midrange horn is used - followed by crossover point and motorboard slot. From what I've uncovered and measured, the optimal woofer polarity choice is not uniform but rather, "customized." Conversely, depending upon the woofer/midrange mix used in the Klipschorn, aligned or reversed woofer polarity appears to matter. My best "hunch" at this point is that this explains the different polarity choice between PWK and EV. (I'm still a little puzzled by the fact that PWK apparently sent Klipschorns out the door until 1958 with random driver polarity wiring - given what contemporary measurements and listening tests reveal) On a practical level, given the amount of effort and interest in "upgrading" the Klipschorn - particularly the replacement of the K400/401 with one of the tractrix midrange horns, I would have to believe this discussion is all the more worthwhile. There is a lot more to cover here, but I wanted to get back to you quickly in the time that I have. -BeFuddledInMn
  14. It took some digging, but I've found an old copy of the EV instruction manual from 1955 - on building the Georgian - the EV version of the Klipschorn, with specific instruction on Woofer polarity alignment below: This corresponds to what I had read years ago in another EV report that described the issue in more detail. The Georgian crossover point from woofer to midrange was 300hz, not the 500hz of the Klipschorn at that time, but the EV engineers felt pretty certain that the woofer polarity alignment 1) made an audible difference and, 2) had a definite perspective on which choice was optimal, and why. As I recall, the x336 crossover EV used here, incorporated a 2nd order high pass filter on the midrange as well. In any event, the phasing and transition challenge presented by the Klipschorn bass horn length should be the same. No? -BeFuddledInMn
  15. In my experience, both listening to and measuring Klipschorns, both room and corner issues can be decisive. Long vs short wall positioning, total room length and width, ceiling height and furniture placemeant all come into play. Of course, sufficient corners with about 4'+ of clean wall space is very important. In my experience with the Klipschorn, real world measurements from listening distances in any room, will vary considerably from factory response measurements. Getting back to the Klipschorn woofer polarity puzzle, I think there have been a number of good points raised in the discussion, including bass horn length and phasing, bass horn behavior across the woofer range with peak horn efficiency, and the ability of crossover slopes to mitigate the corresponding issues in the midrange transition. However, I believe the woofer polarity challenge is far from resolved. Further, dozens of measurements with several,woofer and midrange horn combinations appear to confirm that there is a lot going on with this in the Klipschorn. I don't have the time to post all of the measurements and what I've learned, but it's clear from testing that woofer polarity does impact performance - both measured and heard ( particularly with material that emphasizes the affected range of ~250hz- 500hz) and, the optimal polarity alignment is dependent upon several factors, including crossover point and midrange horn used, among others. Both the degree and location of "destructive interference" between the woofer and midrange is in play, along with the correspondent degree and location of measured distortion. As someone said, there's a lot going on here. Moreover, understanding this challenge should, in my opinion, be of interest to anyone interested in "upgrading" or optimizing Klipschorn performance. I had a chance to pose the issue to Jim Hunter and Roy Delgado in a recent historian thread " Klipsch Licensed Enclosures" Here's a copy of my comment there on April 29th: " Great stuff! One of the most interesting things about BOTH the Patrician and the Georgian is the fact that EV specified and used a reversed woofer polarity arrangement. A few years ago, I read an EV manual description of exactly why this was done - to align phasing in a Klipsch-based design where the folded horn travel length created phasing challenges when integrating with the midrange horn. The EV Patrician assembly documents that WMcD has once again so kindly posted, point that out as well, although they don't go into detail. I've posted a thread on the Klipschorn Woofer polarity issue, but this Patrician discussion should be very instructive IMHO. We know that Klipsch didn't observe any polarity specification at all on the Klipschorn until 1958, and then instituted a matched polarity alignment between all drivers. Interestingly, the copyright dates on the EV documents WMcD has provided, demonstrate that EV was well aware of, and specifying the need for phasing alignment through REVERSED woofer polarity with the Klipsch-based design - at least as early as 1955! More still, the documents I read years ago described a very audible difference to EV engineers with particular reference to a real deficiency in a key octave range if the polarity / phasing issue were not addressed properly. I will look through all of my old documents to find that discussion. Meanwhile I'm pondering a few thoughts/questions: 1) Did PWK really not hear a difference or believe that the polarity/phasing issue mattered until 1958? 2) Why, when the Klipschorn driver polarity did become specified in 1958, was the matched polarity chosen as opposed to the EV perspective/testing? 3) Is it possible that EV engineers knew something about the Klipschorn that PWK didn't, ( hard to accept ) or that PWK simply didn't want to address it? (EV designed and built the EV 15wk woofer used in the Klipschorn and Georgian, so presumably understood that better) (May reflect school of perfection vs school of "good enough") 4)I wonder which way Vitavox, the English Cadillac of Klipschorn copies, went with woofer polarity? My own testing suggests there is a lot going on here, but I'm reserving judgement. Does Jim Hunter or Roy Delgado have some perspective they'd like to share on this? " -BeFuddledInMn
  16. Great stuff! One of the most interesting things about BOTH the Patrician and the Georgian is the fact that EV specified and used a reversed woofer polarity arrangement. A few years ago, I read an EV manual description of exactly why this was done - to align phasing in a Klipsch-based design where the folded horn travel length created phasing challenges when integrating with the midrange horn. The EV Patrician assembly documents that WMcD has once again so kindly posted, point that out as well, although they don't go into detail. I've posted a thread on the Klipschorn Woofer polarity issue, but this Patrician discussion should be very instructive IMHO. We know that Klipsch didn't observe any polarity specification at all on the Klipschorn until 1958, and then instituted a matched polarity alignment between all drivers. Interestingly, the copyright dates on the EV documents WMcD has provided, demonstrate that EV was well aware of, and specifying the need for phasing alignment through REVERSED woofer polarity with the Klipsch-based design - at least as early as 1955! More still, the documents I read years ago described a very audible difference to EV engineers with particular reference to a real deficiency in a key octave range if the polarity / phasing issue were not addressed properly. I will look through all of my old documents to find that discussion. Meanwhile I'm pondering a few thoughts/questions: 1) Did PWK really not hear a difference or believe that the polarity/phasing issue mattered until 1958? 2) Why, when the Klipschorn driver polarity did become specified in 1958, was the matched polarity chosen as opposed to the EV perspective/testing? 3) Is it possible that EV engineers knew something about the Klipschorn that PWK didn't, ( hard to accept ) or that PWK simply didn't want to address it? (EV designed and built the EV 15wk woofer used in the Klipschorn and Georgian, so presumably understood that better) (May reflect school of perfection vs school of "good enough") 4)I wonder which way Vitavox, the English Cadillac of Klipschorn copies, went with woofer polarity? My own testing suggests there is a lot going on here, but I'm reserving judgement. Does Jim Hunter or Roy Delgado have some perspective they'd like to share on this? -BeFuddledinMn
  17. It looks like we're getting all the pieces out on the table here thanks to the many great contributions, but I have to interject for a moment with a bit of a laugh...... In looking for Paul Klipsch's thoughts on the topic, I came across this piece from 1961 in reference to polarity and phase: Too bad I couldn't locate the referenced report, but I had to chuckle a bit here because it would appear that if PWK were still here, and were to visit our forum, he might not stop talking for two weeks, lol. - BeFuddledinMn
  18. Wvu80, I appreciate your point. To help clarify my approach here, I must first say that I too am a student here, and don't have any theory or theoretical depth on the subject to pose to the forum but instead, a lot of questions. In measuring Klipschorn performance which I've posted in the thread "comparing vintage Klipschorn woofer, motorboard, midrange performance, etc....." , I literally stumbled upon this puzzling woofer polarity question. I'm simply hoping that the way I've introduced the issue will bring out as much knowledge on the subject as is possible. My comment you quoted wasn't meant to be a complaint about not getting a free education, just an observation - more in line with "gee, maybe there is a real mystery here." I think your input has been very helpful clarifying what could be misconstrued. I wish I did have the answers here, but simply put, I'm stumped and have raised the issue to learn. Apologies to any and all if if it has seemed otherwise. - BeFuddledinMn
  19. WMcD, When changing woofer polarities, I have measured differences of 5db on the modern K33/3x13 Klipschorn, and as much as an 8db variation in the crossover region with the older style 6x13 motorboard slot Klipschorn, so you'd think it would be clearly audible to just about anyone. The implications of your statement are both interesting and potentially profound! It's very unfortunate that once again, PWK, Max Potter and others, aren't here to help illuminate the subject further. - BeFuddledinMn
  20. John, thanks for your insights on Klipschorn behavior and woofer polarity. I think that your knowledge of the fundamental workings of the Klipschorn - as a horn - with variable horn loading properties within the woofer range - is very helpful here and well communicated/illustrated. Thus far in the discussion, we've considered the impact of horn loading/unloading and gentle slope networks in creating some level of "destructive interference", and thus the results illustrated earlier with the Klipschorn. If we accept that with the Klipschorn there will be an inevitable amount of "destructive interference" between the woofer and midrange horns, we are still left with the question as to which woofer polarity option - which appears to offer a choice on the "destructive interference" position along the 200-500hz range, is "correct" and why? If we consider the two disguised options - matched or reversed woofer polarity - as illustrated in measurements with a standard Crites/k400/k55/"a" network below, does theory or known Klipschorn behavior suggest which is the "correct" choice? - BeFuddleinMn
  21. That is a fantastic piece of Klipsch history in amazing condition! Museum quality! I wouldn't be surprised if the Klipsch company inquires about purchasing it. I don't know if you'll be able to find a match - especially all original in that condition, as early vintage Cornwalls are exceptionally hard to find. Thanks for sharing! -BeFuddledInMn
  22. I own Lascala's and have listened and measured both ways, so I'll share what I've learned. The Lascala with the AL crossover attenuates the midrange -6db, while the AA attenuates the midrange -3db. Most, including myself, believe the -6bd of the AL network is a bit much, but it's really personal preference and room acoustics. However, the AL network Lascala will have a softer midrange and slightly more pronounced bass, which may or may not be helpful in the center depending upon what your objective and listening use is. Myself, I would match AA networks as John suggests, and if doing home theater, do the opposite of your situation, softer minds on the sides, more pronounced minds in the middle channel. As far as drivers, I would match those as well, as a second step. There are measurable differences between the K55v's and the K55m's on both average sensitivity (minor ~1db) and more importantly, mismatched response characteristics across the midrange frequencies. More and more, I believe in new diaphragms across the board as well. You may have a tweeter mismatch as well, but in my opinion, that much less important unless one or more tweeters are worn out. For what it's worth, I've posted some midrange comparisons with K55v and m drivers in the technical section under "comparing vintage Klipschorn Woofer and midrange performance." Best, -BeFuddledInMn
  23. Thank you very much gentlemen. Khornukopia, Complete agreement. I've always believed that room conditions are the single biggest factor in speaker sound performance in terms of frequency response. And it fits well with PWK's belief that frequency response was the fourth priority in terms of judging a speaker. I would have to agree as well, that the Klipschorn is a tough one to measure. To help clarify my work here, you'll note from the first set of graphs that I've measured not only the woofer/midrange combinations under both polarity scenarios, but also included separate overlays of the woofer and midrange traces as well - measured in the same room, same time, same distance, etc. My experience has been that setting a mic on axis about 8ft out from a Klipschorn in a proper, unobstructed corner, with a height equal to dead center of the midrange, captures the in room performance measurement that a listener would hear. Is the sound and measurement "room contorted"? yes, but all of the traces that I've done to display this polarity puzzle, are on the same room playing field. Wirrunna, I either missed, or forgot the potential connection with the Al Klappenberger piece, thank you very much. It makes sense when considering that any slope greater than a first order, would by definition reduce the likely interaction opportunities which would create polarity discord to begin with. Of course, PWK used the first order approach for a long, long time, and more puzzling, didn't publicly observe driver polarity alignment for a significant period of time. In any event, it's always humbling to go down the path and stumble on a sign that's says "Al" or "Bob" etc, was already here, lol. Thanks much for bringing it to my attention! When testing the polarity alternatives, I noted the second order harmonic distortion created under each scenario, and again, there was a tradeoff with each. I've considered that perhaps one polarity option may measure and theoretically look more correct, but conceivably sound worse - per the singing in the shower analogy. But when you have a 5-7db frequency response difference in a crossover region, it's hard to imagine that PWK didn't notice that in the 1950's. In the absence of a factory polarity standard, did PWK believe then that it made no difference to the ear? -BeFuddledInMn
  24. WMcD, I've always appreciated your informed, clear and insightful contributions in the forum, and your comment here is no exception. I've always understood the internal speaker polarity issue as you've described the issue - polarity alignment creates a sum of parts in the crossover regions between drivers, while a polarity reversal, or mismatch creates a cancelling or, as you've put it so well, "destructive interference." Having done a lot of testing/measurement of Klipschorn performance over the past year or so, what I'm finding is "destructive interference", as illustrated in the first set of graphs above, appears to occur on either side of the woofer/midrange crossover region, depending upon the polarity choice one chooses. Neither choice appears to deliver a clean, sum of parts result in measurements. Thus, apparently, one is left to choose between "destructive interference" occurring in the 275-350hz range, or the 375-500hz range, more or less. So it would appear that another way to pose the question I raised initially is to ask whether it is better with the Klipschorn to accept the "destructive interference" in the relatively lower, or relatively higher band of the woofer/midrange crossover region. In any event, it seems that something is either wrong or there is a Klipschorn puzzle here. The issue here seems to hold true across the range of woofers, midrange horns and crossover points used by Klipsch, but I've observed that the relative magnitude is different, as illustrated earlier above. One suspicion is that the optimal polarity choice may be different for different Klipschorn woofer/midrange combinations and crossover points. I've left the polarity options disguised to produce a fair discussion on theory and practice, but unfortunately this thread hasn't generated much discussion. With your permission, I'll PM you. -BeFuddledInMn
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