Jubilee Alternate Folding

[Edgar]

I've seen a lot of references here to "ugly" Jubilees. So I sat down this morning with a copy of the original Klipsch/Delgado JAES paper and TurboCAD, to see if I could change the external appearance while keeping the internals the same. The graphic shows what I came up with. It is now a true corner horn. The shape of the backchamber is different, but the volume is the same. The horn follows the taper described in the JAES paper almost exactly, in fact the "A", "B", "C", and "D" callouts correspond to the similarly labeled points in the paper.

Note that I haven't built this, only fiddled with it in CAD. But maybe it will give some of the DIYers some inspiration.

[Guest " "]

That looks real good.....please submit a patent on it before Roy does.

[ajsons]

Or one a-ho from Washington state.

[bluesboy]

Here's an idea. How about Edgar's bass horn design with a large format Altec horn and driver on top?

[ajsons]

Edgar,

Nice folding, but I don't think it will take care of the plug ugly situation.

With 2 180 degree folds and mouths well separated, it will not perform like the jub.

Bluesboy, I think you mean Bruce Edgar.

Which bass horn though?

[Edgar]

Here's an idea. How about Edgar's bass horn design with a large format Altec horn and driver on top?

Won't fit without hanging-over the edge. The 805 and 1005 are 17+" deep, plus 4½" for throat, plus maybe 6" for driver. The bass horn is only 25¼" from the corner to the front face.

[Edgar]

Edgar,

Nice folding, but I don't think it will take care of the plug ugly situation.

With 2 180 degree folds and mouths well separated, it will not perform like the jub.

 

Like I said, just fiddling with CAD. Sometimes it's good to stimulate the imagination.

On edit:

PS "Edgar" is just my forum name; I have no relation whatsoever to Bruce Edgar. I took the name from Edgar Montrose, a character on the Red Green show who likes to blow stuff up.

[bluesboy]

How about a 511 horn with a 902 driver?

[mikebse2a3]

Interesting folding.

The problem I see with this is the folding has even more turns and they are higher in degree also versus the Jubilee folding which I suspect would create a rougher response with an earlier cutoff versus the standard Jubilee.

Remember in the AES Jubilee Paper when the folding was held closer to the Klipschorn by staying next to the room's side walls the increased performance seeked did not happen. The width of the front panel(ie distance between the bifurcated horns mouth) chosen was a critical part of the design to acheive the improved performance.

mike tn

Note the test performance differences in the paper!

[bluesboy]

Really the idea I've been toying with is the existing Jube bass bin with a 1005 horn and 288 driver on top.

[Edgar]

How about a 511 horn with a 902 driver?

The 511A is 18½" deep but doesn't need a separate throat. Might work.

http://www.voiceofthetheatre.com

[Edgar]

 

Note the test performance differences in the paper!

The frequency response associated with Figures 4 and 6 is in Figure 5, not in Figure 9. Compare Figure 5 with Figure 8, and below 500 Hz they're pretty similar.

[mikebse2a3]

Yes you are correct Edgar and here is Fig 5.

The Jub still exhibts several db tighter response and because of our hearing sensitivity in that range I would expect it to be noticable.


mike tn

[Duke Spinner]

Bwaaahahahah .....

good one, AJ

[Edgar]

Here's another one. This one is 28½" from corner to face, so the 500 Hz Altec horns will fit.

Again, I'm just playing with my CAD program. I wouldn't dream of second-guessing Paul Klipsch or Roy Delgado. But I do like to think about what could be ...

[bluesboy]

That looks sweet. Let's build one.

[seti]

Here's another one. This one is 28½" from corner to face, so the 500 Hz Altec horns will fit.

Again, I'm just playing with my CAD program. I wouldn't dream of second-guessing Paul Klipsch or Roy Delgado. But I do like to think about what could be ...

That is a very coool jubilee inspired looking folded horn you've got there.

[mikebse2a3]

Hey Edgar

I like that second drawing [Y] especially were the mouths come together. Would really be interested to see that one built and tested for frequency and especially polar responses.

mike tn[]

[Edgar]

Here's the HORNRESP response for that design with two EVM-12L inside (which I used because I just happen to have four of sitting unused in boxes). Of course, HORNRESP cannot model the effects of the folds.

And here's the HORNRESP.DAT file info: 0.5 x Pi 2.83 0.00 14.99 580.00 816.00 23.53 0.00 816.00 1727.40 59.75 0.00 1727.40 2817.66 29.45 0.00 2817.66 5527.15 44.81 0.00 500.002.12E-04 32.00 5.20 17.50 3.30 0.50 2P 80.00 40.00 0.00 20.00 4.00 376.00Two EVM12L; Alternate Jutilee 3 ConConConCon

[mikebse2a3]

In looking at Edgars 2nd drawing versus the Jubilee the mouths come back together and It would be interesting to see how the different fold locations would change the frequency response(different fold locations and cancelation effects etc..) versus the Jub. I would expect there to be some advantage in the polar response as far as lobing due to the speaker itself having in effect one mouth. At this Time I have been excluding the room.

Now for my real world question. Assuming we want to corner load these two horns(Edgars and the JUB) I wonder could there be an advantage to having the bifurcated mouth horn acting as two seperate sources in relation to the corner boundaries versus a single horn mouth and the same boundaries. This is assuming that both horns are snug in the corners and not rotated so that the mouths of even the single horn is at different distances from the side walls which would be another avenue to investagate also.

So! If we could build a Jub or any horn with a single mouth for instance would we want to?

Part of the answer might depend on how high in frequency we needed the horn to work I believe and Right off the top of my head I can see that because of the real world corner and it's mirror image effects that there are still going to be lobing effects for both types of horns and so maybe the answer would be that depending on the listener's room and listening location in relation to the lobes that neither horn would necessarly be superior but one type might work a little better versus the other in certain situations.

mike tn