ZAKO Posted September 20, 2015 Share Posted September 20, 2015 GOOD POINT,,,Whos going to make another Plexi glass Bass Bin,, to show this,,? 1 Quote Link to comment Share on other sites More sharing options...
LarryC Posted September 20, 2015 Share Posted September 20, 2015 Plus all 155 tech letters from Paul to George... I sent copies to Jim Hunter... I haven't read them in many years,,, The additional wedges in the bass bin are a mystery to me,,, I don't remember who ,,cant remember his name also found these wedges in the bass bin and was able to remove them.. Coming in late (as usual) on this thread...the "mystery pyramid" in front of the bass driver is really called a splitter bar. Paul told me long ago that this improved the response at the top of the bass bin's range. My interpretation is that at the frequencies involved, and with the geometry of the motherboard, this acts somewhat like a phase plug at the very top end. Recalling that the purpose of a phase plug is to make the path length from all parts of the diaphragm to the throat the same; at the frequencies of interest here, the effect would be the same. We are probably describing two different "pyramids" or "wedges" here. One is the "splitter" which is attached to the FORWARD wall of the first stage of the bass horn, directly in front of the center of the bass driver, and opposite the 3 X 13 slot in the motherboard . It runs parallel to the slot, and has a triangular cross-section. The "wedges" that ZAKO mentions are also triangular in cross-section, but there are a pair of of them, running the length of the 3 X 13 slot and parallel to it, one positioned along the top of the slot and the other along the bottom of the slot. This places both directly on front of the motorboard, and on the REAR wall of the first stage of the bass horn, opposite the splitter. This has the effect of narrowing the throat passageway following the slot. I'd have to dig out the pics of my bass horn thread, to make it any clearer. I wish those pics had survived with the thread. Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted September 20, 2015 Share Posted September 20, 2015 Plus all 155 tech letters from Paul to George... I sent copies to Jim Hunter... I haven't read them in many years,,, The additional wedges in the bass bin are a mystery to me,,, I don't remember who ,,cant remember his name also found these wedges in the bass bin and was able to remove them.. Coming in late (as usual) on this thread...the "mystery pyramid" in front of the bass driver is really called a splitter bar. Paul told me long ago that this improved the response at the top of the bass bin's range. My interpretation is that at the frequencies involved, and with the geometry of the motherboard, this acts somewhat like a phase plug at the very top end. Recalling that the purpose of a phase plug is to make the path length from all parts of the diaphragm to the throat the same; at the frequencies of interest here, the effect would be the same.We are probably describing two different "pyramids" or "wedges" here. One is the "splitter" which is attached to the FORWARD wall of the first stage of the bass horn, directly in front of the center of the bass driver, and opposite the 3 X 13 slot in the motherboard . It runs parallel to the slot, and has a triangular cross-section. The "wedges" that ZAKO mentions are also triangular in cross-section, but there are a pair of of them, running the length of the 3 X 13 slot and parallel to it, one positioned along the top of the slot and the other along the bottom of the slot. This places both directly on front of the motorboard, and on the REAR wall of the first stage of the bass horn, opposite the splitter. This has the effect of narrowing the throat passageway following the slot. I'd have to dig out the pics of my bass horn thread, to make it any clearer. I wish those pics had survived with the thread. Is this the picture your looking for Larry? https://community.klipsch.com/index.php?/topic/23463-changing-the-throat-area/ 1 Quote Link to comment Share on other sites More sharing options...
LarryC Posted September 20, 2015 Share Posted September 20, 2015 Is this the picture your looking for Larry? https://community.kl...he-throat-area/ Attached Thumbnails Exactly!!! Wow, do you have the rest of those pics? Anyway, that's the drawing I did. Were you able to pull it out of that old thread, or did you just store it up just in case!! =- Larry Quote Link to comment Share on other sites More sharing options...
ZAKO Posted September 20, 2015 Share Posted September 20, 2015 And what do the Khorns have today,,??? 2 Quote Link to comment Share on other sites More sharing options...
boom3 Posted September 21, 2015 Share Posted September 21, 2015 OIC, I forgot about those. I can only think they are a part of the pseudo phase plug I mentioned earlier, and work together with the splitter bar.. I'm sure that Klipsch has not forgotten what they are for, perhaps Jim Hunter will see this thread. Quote Link to comment Share on other sites More sharing options...
mikebse2a3 Posted September 22, 2015 Share Posted September 22, 2015 Is this the picture your looking for Larry? https://community.kl...he-throat-area/ Attached ThumbnailsExactly!!! Wow, do you have the rest of those pics? Anyway, that's the drawing I did. Were you able to pull it out of that old thread, or did you just store it up just in case!! =- Larry Just pulled it from that thread. Quote Link to comment Share on other sites More sharing options...
LarryC Posted September 22, 2015 Share Posted September 22, 2015 Just pulled it from that thread. I can't pull any of those pics from that old thread. There are other pics that show the actual inserts I pulled out, etc. Maybe a different browser> Hm. Quote Link to comment Share on other sites More sharing options...
BeFuddledinMn Posted September 22, 2015 Author Share Posted September 22, 2015 LarryC, That's a great illustration you made of the wedges inside your Klipschorn motorboard. Great detail and measurements! Can't ask for more than that. Thanks much to mikebse2a3 for finding it! I think this discussion has been very helpful. Mounting boards and woofer tests still planned for October. Should be interesting. Quote Link to comment Share on other sites More sharing options...
horatio2 Posted September 23, 2015 Share Posted September 23, 2015 I have been reading and researching the 6x13 vs 3x13 slot issue with great interest on this site. I wonder, BeFuddledInMn, if doing your tests using straight drive to the bass horn would not be better than trying to sort crossover matching with passive crossovers. It certainly would lend itself much better to A-B comparisons with woofers and slots, given how the impedance can dance about and make the crossover so vitally important to the sound. I might suggest using a MiniDSP ($100, easy enough to use, performs quite well, no affiliation, just satisfied user) to do the crossover function, and drive with a solid state amp so that the usual tube amp damping factor issue is not present, either. Finally, since there has been much discussion of the EV 15-WK driver: reading the EV datasheet would suggest that the EV15W is also a good bet, if one does biamp/triamp, so that the woofer impedance for the 15W is a non-issue. Any thoughts on that? It'd be really nice if anyone has T/S data for the EV 15W, WK, Stephens Trusonic P52LX2 or 103LX2, and Jensen P-15-LL would post it. Part of the Khorn mystery is how this horn works so well, but follows non-standard drivers- how to pick, how to match (other than rank empiricism). Saw some T/S data for EV 15WK that looked pretty close to a Kappa 15C, except fs on the EV was quite high- 42 or thereabouts. If PWK treated the accordion of the EV to get Fs down to 30-32, then a Kappa 15C driving a 6x13 slot oughta be pretty good. -M Quote Link to comment Share on other sites More sharing options...
Axz Hout Posted September 24, 2015 Share Posted September 24, 2015 T Quote Link to comment Share on other sites More sharing options...
horatio2 Posted September 24, 2015 Share Posted September 24, 2015 Another comment for this thread. I run factory build Speakerlab K's. When I got these, they had EV 15L's in them, running with the Speakerlab crossovers. Sounded terrible. I put in the original 4 ohm Speakerlab drivers (W1504S, as I recall), and did not care for those, either. I bought K33E's and those woke up the bass. Got even better when I built a Klipsch A or AA (can't recall which, now). Here, I now had a bass horn with the same geometry (3x13 throat, and all else) as factory Khorns of the same era. I have been intrigued with comments that have been posted, littered all about this site, regarding the sound of those 1950's Khorns (with the 6x13 throats) and the big 50's alnico drivers. And I have seen reference to the altered frequency response brought about by the small throat and the K33E. Most of those seem to focus on the somewhat improved response above 300 Hz, but some reference the altered low end and overall response from this combination. I am after restoration of this altered low end on my system. I do not care as much about response above 300 Hz, as this has been the traditional (and stubborn to fix without revisiting the whole folding scheme ala Jube) weak spot of the Khorn design, and I find it better to sidestep it altogether by getting a midrange that can reach down a bit further. But the deep bass response is another thing, and I would be willing to open the slot to 6x13 and run something like a Kappa 15C if I knew this would provide what I am looking for. Most of the sore spots with the Khorn concept can be readily dealt with in a way that is remarkable if one goes two (or maybe three) way, using a midrange that goes deep and attends to directivity concerns, and biamping/triamping digitally so that time alignment and other details (like being able to work with a constant directivity horn) can be dialed in. A set up like that is in another category altogether from the OEM Khorn. I run a setup this way, and have found my own nirvana with it. But I would be interested in returning the bass section to the classic Klipsch geometry, with the 6x13 throat, provided adequate drivers can be identified. My perception from what I've read would suggest better bass performance in terms of low end and smoothness of response. Has anyone on this thread collected bass response curves for the various bass horn production examples, so that the characteristics can be compared? I recognize that this would primarily mean finding curves from Hope; those would probably have the best chance of comparability. -M Quote Link to comment Share on other sites More sharing options...
ZAKO Posted September 24, 2015 Share Posted September 24, 2015 Yes I have many of the bass curves from the early Khorn done by ashworth,,, using both 3x13 and 6x13 throat boards,,,, They are pretty crude compaired to the plot recorders of today,,,But finding those files will take some time,, 1 Quote Link to comment Share on other sites More sharing options...
horatio2 Posted September 24, 2015 Share Posted September 24, 2015 ZAKO: That'd be great! I realize that comparing those must be done intelligently, inasmuch as the measurement method may well have something to do with what is seen (I'm guessing that Klipsch's anechoic chamber didn't exist then). But it will certainly enable one to muse over the choices and consequences. I am looking forward to those, if you find them! Quote Link to comment Share on other sites More sharing options...
Axz Hout Posted September 24, 2015 Share Posted September 24, 2015 A Quote Link to comment Share on other sites More sharing options...
boom3 Posted September 25, 2015 Share Posted September 25, 2015 Aren't we talking about the Type G motorboard? Dope From Hope, Vol. 2, No. 12, 10 November 1961. Paul calls this a "multitude taper". He mentions the Type G again in Vol. 12, No. 5, June 1974; edition revised February 1982 Quote Link to comment Share on other sites More sharing options...
LarryC Posted September 25, 2015 Share Posted September 25, 2015 This is the best sound from the K bin I have so far. The old EV 15W/15WK will not run at 25v RMS very long. Twenty-five volts??? I don't understand the application of this -- in the bass horn, at an efficiency of perhaps 30%, the 15WK will probably run at milliwatts for huge sound output. I'm glad you will be testing your various configurations and combinations. Of course, I confirm everything by ear, i.e. how closely does it sound to the real thing? 1 Quote Link to comment Share on other sites More sharing options...
BeFuddledinMn Posted September 25, 2015 Author Share Posted September 25, 2015 We continue to get a lot of good input, information and knowledge sharing on these topics. Thanks again to EVERYONE who has contributed here! Horatio2: Your points on testing are well taken. I will begin the testing with a straight no-filter signal to each of the woofer and woofer board combinations to get a baseline on the unfiltered response, sensitivity and impedence characteristics. Testing will be done with a mosfet equipped adcom 5400 solid state amplifier at 125 watts per channel fed through an adcom GFP 600 preamplifier set to mono output. More to come later on the testing equipment. I may be adding both k-33P and k-33B woofers the mix, and possibly an Eminance Kappa C. After this level of testing is done and recorded, I plan on introducing crossover networks ("a" type variations) to the various woofers and boards with various inductor values to establish best performance for each with crossover at 400 - 450hz. I plan to then follow this all with a full range comparison with both K-5-J and K-400 mid range horn setups. - BeFuddledInMn Quote Link to comment Share on other sites More sharing options...
horatio2 Posted September 25, 2015 Share Posted September 25, 2015 Great plan- I will be very interested in the results, as I am sure many others will as well! Quote Link to comment Share on other sites More sharing options...
djk Posted September 25, 2015 Share Posted September 25, 2015 " at an efficiency of perhaps 30%" At a couple of peaks near 200hz, otherwise less than 10% below 100hz or so. Quote Link to comment Share on other sites More sharing options...
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