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Is this a k77 tweeter or not?


rplace

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Maybe this is crazy you guys tell me. I have been kicking abound the idea of build different tops for my khorns. They would be constructed such that they would not have the "home plate" looking top piece. My design is still in the thinking phase, but I figure by not having the back/sides extend all the way into the corners I could then pivot the HF section out a bit to widen my sweet spot and sit further back.

The down side to this would be that I would need to pirate my current parts to put into my prototype. Having an complete extra set of hight/mid drivers and horns would make the swapping and comparison to original a lot faster and hassle free.

Would that horn/driver be a good start to the parts needed to build my prototype or would the fact that my current 87 vintage drivers are the square type be an issue? By issue I mean is there any problem with voicing, different sound, crossovers or anything else?

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The square ceramic magnet K77 are newer versions than this older Alinco magnet K77. I forget the range, but these older tweeters do not have as high freq extension as the ceramic jobs. Sometimes I read a post where someone prefers the sound of the older Alinco tweeter, but I don't know that I've been able to tell any appreciable difference.

I think the ability to "swivel" your HF would be a worthwhile project. If you're not in a real rush, you might check out that thread on the Eminence tweeter. Bob Crites is working on a K77 replacement that sounds very good. I've been listening to a prototype, and to my ears it is a runaway improvement over the K77.

http://forums.klipsch.com/forums/657718/ShowPost.aspx

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I was going to design a "swivel top" but decided not to after analyzing teh problem and just built false corner instead. The problem is the K400's depth. It is so deep that there is not much room to swivel and not hit the wall. You can swap in a set of Al's tracthorns of Altec 511b's (a good idea) but you will still have a problem with swiveling the top. When teh top is turned, the outlet of teh horn will be restricted by the top and bottom of the top enclosure.

Hard to explain, but look at it in plan view and visualize rotating the horn and you will see that the soundwaves leaving the horn will nto be allowed to radiate out 360 degrees from the mouth of the horn. This may not be a big issue, but for me, my K Horns are now much more user friendly with the false corners.

Chris

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TigWKH, interesting. I can't envision this problem in my mind. I have two great corners...they just are not as far apart as I would like.

See my crude drawing below and tell me where I am missing something. Original placement is in red with yellow lines for intersection of sweet spot. New position is towed out a bit in purple with blue lines crossing to form sweet spot. What am I not thinking about correctly?

EDIT: BTW my thinking was to leave the piece of wood in place that makes the riser between the HF and LF section in place. Then construct my new tops narrower (side to side) and shorter (front to back) in addition to leaving out the "corner piece". This way I have a couple of inches on each side and front to back to move forward/back and swivel side to side.

post-16462-13819279151018_thumb.jpg

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Or you could go the 511B route with a set of Bob C's tweeters. You'd get improved clarity, decreased physical depth so they would probably be easier to rotate; the 511b's are about the size L to R and Top to Bottom of a La Scala top section but not as deep. Youd end up kind of looking similar to the 50th anniversary in ratio of top section to bass horn albeit a bit taller.

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I toed mine out even further so that the horn axis is actually outside the listening position.

As a note, the dispersion of the K-77/EV T35 is wider in the vertical placement - it's a diffraction horn.

Klipsch mounts it horizontal for "looks" me thinks, due to the wideness of the midrange horn they use and that prevents the cabinets form being either a "left" or "right" cabinet, which is a manufacturing "pickle", of course.

Theoretically, the tweeter would have wider horizontal coverage if it was mounted in the vertical position.

DM

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It is hard to tell from your pictures precisely what you have. If you post a shot straight on from the side I can give you a better idea. EV had two retail versions of their tweeter: the T-35 that was teamed up with the SP12, SP12B, etc. woofers, and the TW-35 which had a smaller magnet and was matched with the Wolverine woofers like the LS-12. What you have appears to be an OEM version of the TW-35.

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Interesting ideas guys. I am intrigued to say the least. Keep the info coming.

D-man, if I mount the tweeter vertical you say I end up with a Left and Right speaker. No problem there...but does the tweeter go to the "outside" or "inside" of the midrange?

J.4, I'll have to do some digging on that (the search stinks now can you point me in the right direction) hopefully they are recent posts and I can find them.

3dZ, are those just sitting in your HF section meaning they are not attached to anything? Strange look to me as I am not all that knowing in the various horn configurations. I would probably go the buying route versus making my own...but how does one make a horn. That looks to be wood and it is curved am I right? Are the dimensions/tolerances very particular and precise or is it more of a ball park sort of thing. I would imagine it would be hard to bend wood in a very exact manner...but then what do I know [;)]

All, when you start swapping out drivers/horns does this effect your crossovers? I would think so. If so what must be done.

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"3dZ, are those just sitting in your HF section meaning they are not attached to anything? Strange look to me as I am not all that knowing in the various horn configurations. I would probably go the buying route versus making my own...but how does one make a horn. That looks to be wood and it is curved am I right? Are the dimensions/tolerances very particular and precise or is it more of a ball park sort of thing. I would imagine it would be hard to bend wood in a very exact manner...but then what do I know Wink [<img src='https://community.klipsch.com/uploads/emoticons/default_wink.png' alt=';)'>]"

I described building my horns based on Bruce Edgar's article in "Speaker Builder" in this thread:

http://forums.klipsch.com/forums/657225/ShowPost.aspx

At this time, while I experiment with them, they are a friction fit at the front and at the back they sit on the support brace

Rick

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right or left side tweeter mounting - I recommend that you experiment before locking yourself in on that.

I went with the tweeters on the outside for a seemingly wider soundstage.

This introduces some reflection problems with the proximate walls, though.

Also experimentation would confirm the vertical vs. the horizontal coverage to see if that meets your requirements and particulars of the room.

DM

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Dm, With a corner horn and 100 X 100 dispersion, wouldn't the reflection be the same only different inside or outside?

I like mine outside myself.

When I had them on the top, it made Dean nervious if they weren't centered. He thought it upset the karma of the universe. Now, he can't see them.-)

Rick

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rplace, check out the carpentry subthread posts in the LaScala Questions thread in 2 channel.

Your sweetspot is just a few wall relocations away. Has the complete instructions for DIY demolition and construction, and includes an enlightening section revealing the major defect of horn loaded speakers - failing to provide the distortion necessary to properly reproduce bass guitar. (I'm not kidding, looks like PWK may have been all mixed up about this)

Pauln

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Clearer with more "presence" Dee. I can't say louder per se. I left the ALKs at 4 and 0, the same as with the K-400s to appreciate the difference and I'm still evaluating them at that setting. I will try 4 and X to see the difference next. I have a set of L-pads that are in the back room that would be more convient. These days it is a lot of work moving the Belles to move the Ks to get at the xovers and basically, I'm too lazy.[;)]

Really, I have been involved in another project this week that is nearing completion and getting myself ready for the State Championships.

Rick

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