longdrive03 Posted August 15, 2016 Share Posted August 15, 2016 Okay so call me Crazyman but I had two K-77 horn fronts laying around and wondering if I could fit a couple of EV drivers to the horns. I used a plastic female horn adapter and cropped the round edges, epoxied the horn and adapter together and drill two holes on the top side in the adaptor. These will fit in a Heresy cabinet. I screw in the four screws on the horn then two screws through the new holes into the 3/4" glue block to helps support the adaptor and take stress off the epoxy joint. I knocked out the center difuser on the K-77 and am working on cutting/filing down the dispersion ribs on the horn front. The sound is great but need more pad down since it's 110db. Not sure if leaving the ribs makes any difference? Any ideas? Too late now since I've started the process. Quote Link to comment Share on other sites More sharing options...
Marvel Posted August 16, 2016 Share Posted August 16, 2016 The k77 already had EV drivers. It's not a diffuser and who knows what you've created... Really, why would you do that? Quote Link to comment Share on other sites More sharing options...
Don Richard Posted August 16, 2016 Share Posted August 16, 2016 BEC has a replacement for the K-77 that looks somewhat like what you did. I believe it's called the CT-125, and it's sensitivity is 104 dB, a drop in replacement that doesn't require crossover adjustment. Quote Link to comment Share on other sites More sharing options...
wvu80 Posted August 16, 2016 Share Posted August 16, 2016 I have to admit, it looks pretty nuts to just combine random compression drivers with a K-77 horn with no apparent audio goal in mind. It looks like something I would do. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 16, 2016 Share Posted August 16, 2016 It looks like a cool project with some spare crap you have lying around. I say go for it. While you are at it, build a box and put like 5 misc drivers you have laying around in it and use this as the tweeter. Put in a simple 2 way passive network. Wire the thing so it has like 8-10 DCR. You could call this speaker Frankenstein's monster and we will not call you Crazyman because we will call you Dr. Frankenstein. You could sell it on ebay for dollars and dollars! Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted August 16, 2016 Author Share Posted August 16, 2016 I am aware of Bob Crites excellent tweeters having purchased them and living about 50 miles from his shop which I have visited many times. I'm also aware that the K-77 uses an EV driver. I'm also aware per Bob's website that there are apparently no good after market replacement diaphragms for the K-77/T-35 tweeters which is why he no longer carries same. Perhaps I wasn't clear but this was a see what it will do project. I had two EV drivers and two front horns laying around (I didn't take them off a working K-77) and modified the horn to attach a much better EV driver with a titanium diaphragm made in house by EV with a better response. My goal was to see what it would sound like. If it sounds bad then I unscrew the EV drivers and use them on another project and the K-77 horn pieces can go back on the shelf or trash since they weren't working anyway. That's why I did this. I've now removed the ribs and hit it with touch up paint and will final paint tonight. Here's another pic. So now can anyone address my question whether the ribs (for lack of a better term) will make any difference? Mustang, I may give your suggestion serious consideration!!!!!!!!!!!! Thanks. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 16, 2016 Share Posted August 16, 2016 No idea about the ribs. I think they are like racing stripes. They make the speaker "faster". We should have a franken sound competition where the entries create a working sound device, tubes, phono, speakers, or whatever. There are lots of DIY-ers here and lots of them have spare crap laying around. The trophy for the overall winner, could be a frankenstein head that is made of tiny speakers and wires and tubes and stuff by a handy artsy craftsy type person right here on the forum. The winner would be awarded at the 2017 Hope Gathering, and subsequently turn the trophy over to the winner the next year. The entry has to function how ever well. The entry has to be made of a bunch of spare crap they have laying. The entry has to look like something that was made from a bunch of spare crap they had laying around. The entry cannot be something that would look right anyplace nice. Are there more? Have I gone too far? Forget about Steam Punk, we are going to start a new thing called Franken Sound. Brought to the world from the Klipsch forums! 1 Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted August 16, 2016 Author Share Posted August 16, 2016 I could sweep the floor of my dirty shop and come up with an interesting monster. I think I have a few dead bodies in there now. At least two??? Someday I'll clean up and count. Good suggestions. I call that the "sweep the floor special" ala pizza. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 16, 2016 Share Posted August 16, 2016 LOL, throw in some adhesive and you might just make an actual living abomination. How cool would that be? Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted August 16, 2016 Author Share Posted August 16, 2016 Mummy tape dragging the floor with Boris Karloff head with two tweeters for eyes and port for mouth with teeth 1 Quote Link to comment Share on other sites More sharing options...
wvu80 Posted August 17, 2016 Share Posted August 17, 2016 3 hours ago, mustang guy said: No idea about the ribs. I think they are like racing stripes. They make the speaker "faster". I prefer a thick, sweet BBQ sauce with my ribs, if that helps. We should have a franken sound competition where the entries create a working sound device, tubes, phono, speakers, or whatever. There are lots of DIY-ers here and lots of them have spare crap laying around. I love it. The trophy for the overall winner, could be a frankenstein head that is made of tiny speakers and wires and tubes and stuff by a handy artsy craftsy type person right here on the forum. The winner would be awarded at the 2017 Hope Gathering, and subsequently turn the trophy over to the winner the next year. I would name it the No-Hope award, in honor of Mustang Guy. Have I gone too far? Always. That's your charm. Forget about Steam Punk, we are going to start a new thing called Franken Sound. Brought to the world from the Klipsch forums! We have to have a way to determine a winner, with the winning system being able to play back the highest quality music that matches the spirit of the No-Hope Award. 1 Quote Link to comment Share on other sites More sharing options...
WMcD Posted August 17, 2016 Share Posted August 17, 2016 Thank you for sharing your impressive experiment. Don't let the guys here get you down. WMcD 1 Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 17, 2016 Share Posted August 17, 2016 OMG Dave! HAHAHA!! 1 Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted August 17, 2016 Author Share Posted August 17, 2016 Thanks WMCD. Appreciate the encouragement! I sprayed some truck bed liner paint on the horn last night to cover any scratches and it looks pretty good. I mispoke above, and thank Marvel for pointing this out, when I referred to the "diffuser" which really should be a phase plug I believe. The 8442 EV CD has a phase plug. If I'm wrong please correct me. Yeah, Edison was scorned when he failed so many times (okay I realize this is a BIG exaggeration!). I need to get someone local to get some dispersion graphs if possible!!!?? ust to see how "ribless" horn disperses if possible. This project is sticking a knife in a wall socket just to see what happens. No preconceived ideas at all just playing with spare parts.. I like my KC Masterpiece "que" sauce!! Hard to beat. Quote Link to comment Share on other sites More sharing options...
WMcD Posted August 18, 2016 Share Posted August 18, 2016 (edited) I don't know where I found the attached advertisement from EV except I almost certainly off the Internet a long time ago. I don't know why a bit of the right side is missing. IIRC there was an earlier version of the T-35 without the button phase plug and this ad shows Mr. Avedon at EV came up with the new arrangement which EV touted. This was the late '50s when microgroove vinyl and FM was getting up above 8 kHz. PWK's earlier tweeter was from another source (?) but given his close relation with EV he must have jumped on it to maximize performance of his units. You'll note there is a version shown with a smaller magnet. This might have later become the more obscure Wolverine version. The T-350 (bigger magnet) is famous though. Regarding the ribs: There is no claim in the ad that they contribute anything to scattering or diffraction. They may be a little too small (not tall) to affect it. The wavelengths are about one inch and these are, what?, about 1/4 to 1/16th inch. OTOH, maybe they do something to channel the sound to the farther ends of the horn. In your set up, or Crites, the driver may very well have an internal phase plug. On the other had, the button is forming a ring radiator which when mounted just at the throat of the horn may have some benefits. I believe the forum should encourage experimentation like yours. WMcD EV Avedon T35.pdf Edited August 18, 2016 by WMcD Typos 1 Quote Link to comment Share on other sites More sharing options...
WMcD Posted August 18, 2016 Share Posted August 18, 2016 Another interesting document is the U.S. Design Patent on the T-35 (attached). Design patents cover only the appearance of the device whereas a "utility" patent would claim an invention. Therefore there is no technical discussion or "claim" beyond what is shown. In the past I posted the design patent on the Belle. And FYI, there was one on the Porsche Targa top. Both now lapsed of course. Again they claim the appearance. However the line drawings are beautiful. It is not possible to get into the head of EV or their attorneys. It may be that the structure of the phase plug and intermediate structure was already known. I can't say I've looked for a utility patent on the subject but EV should have mentioned it in the ad if there were one. Perhaps it would have described the function (if any) of the ribs. Edit: Note the reference cited section shows the ad is from 1954. WMcD Avedon Design Patent on T35.pdf 1 Quote Link to comment Share on other sites More sharing options...
longdrive03 Posted August 18, 2016 Author Share Posted August 18, 2016 Gil, You're as handy as a pocket on a shirt!!! Thanks for you comments and links. You truly are an outstanding source of wisdom and information. I'm about to wrap up the painting (high humidity here) and play with it this weekend. As I recall the Motorola piece horn tweeter that is similar in size to the T35 doesn't have any ribs but does have a different shaped phase plug and probably horn shape. Food for thought. Quote Link to comment Share on other sites More sharing options...
wvu80 Posted August 18, 2016 Share Posted August 18, 2016 Could the ribs be for structural strength of the horn? Quote Link to comment Share on other sites More sharing options...
WMcD Posted August 18, 2016 Share Posted August 18, 2016 Thanks for the kind comments LD. Dave, I don't know. The horn seems fairly beefy to me. If the choice was for esthetics, it was a good one to my eye. Quote Link to comment Share on other sites More sharing options...
WMcD Posted August 18, 2016 Share Posted August 18, 2016 You can read about the history of the tweeter, and other drivers, here. https://2d73e25b29782b6d6766-9c8af5cbfef16739445bc76457060528.ssl.cf2.rackcdn.com/KhornTimeline_635116436015580000.pdf Quote Link to comment Share on other sites More sharing options...
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