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wings on Jubilees?


juniper

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  • Klipsch Employees

I don't believe that I'm going to be able to answer your rhetorical questions (i.e., questions that aren't really questions, but arguments) in the space limited here to "Wings on Jubilees".  I'm not sure that you even want me to answer any of your questions, so I'll wait until you start up a thread on that subject, then I'll attempt to answer any questions that I can ascertain are questions, and that I believe can help.

 

Just one thought to munch on until that time:

 

On a folded horn (with or without dual bifurcated mouths), where do the final high frequencies originate and how much of the horn's path do they actually use to form their pattern before exiting the horn mouth(s)?  I'd also recommend thinking about Danley's multiple-entry horn designs (which, of course, you believe don't work as advertised, but I actually do.)  Think also about equivalent bandpassed filters in parallel and in series. Think about "evanescent modes" and the "cut-on frequency" of a horn segment -

f(co) = 1.84c/2πa

 

Chris

Evanescent and cut-on freq? Cool terms. Maybe too cool for me.....
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  • Klipsch Employees

So just to be clear, you don't have any numbers indicating this alleged improvement? No dimensions or design targets for the people wanting to actually implement something? No data from other designs?

I think it's only natural to consider adding a nose alongside the wings if you're gonna go through all that work. Misconstrue my motives all you want, but these have only been serious questions. Your disrespectful attitude is unappreciated - which is extra annoying because you're actually well read. Try to smile sometime - I hear it's good for the soul.

Smiling comes a lot easier after a brew or 6......
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  • Klipsch Employees

I need to get around to using Akabak more freely - I feel like it is capable of modelling some of these ideas - I'm just not comfortable enough yet to trust the results.

 

 

Actually, the plots that I've seen of AkabaK and Hornresp plotted with actual measured SPL/frequency on these type of horns show that Hornresp does a lot better at lower frequencies (below 2 kHz) and AkabaK does better above that point (assuming that you can model it in Hornresp). 

 

 

I'm not convinced it'd improve the HF polars though...once you bifurcate, you're dealing with two acoustic sources.

 

 

Having two horn mouths emitting side by side at greater than 1/4 wavelength separation induce polar cloverleaf patterns and other diffraction artifacts (including interference maxima)--that are much worse than combining mouths together again internally.

 

I think that the same issue appears when combining two line array speakers together as a common acoustic source (assuming symmetric paths).  For instance, Danley claims that their designs achieve wave summation (not cancellation) at the boundary between the horn mouths.

 

Chris

Is that why phase plugs don't work?
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  • Klipsch Employees

In my spare time, which isn't much these days, the nosepiece along with extending panels on top and sides, does in fact lead to improvement. In something as invisible as those stupid acoustic waves are, there is something missing......got to get some free time to find it. Remember my friends this is supposed to be fun......

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What can I say? I'm a data driven guy. I've actually built some speakers to explore this idea a bit. The nose had to be really long before it 'fixed' the problem, but even then it still existed.

I'm at the point now where I want to explore having the acoustic sources fire across each other (much like a phase plug), but I could see that being a very difficult exercise in balancing the outside edge diffraction. I thought I'd get there with some of my experiments, but the outside diffraction threw it off - or so I thought.

Anyways, that approach would necessitate handling the "wings" differently - which is the original reason I brought it up here...

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What can I say? I'm a data driven guy. I've actually built some speakers to explore this idea a bit.

 

What data?  Did you post it?

 

Chris

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Unique to every THX Certified Cinema is the THX “baffle wall.” If you were to peel away the screen at any THX Certified Cinema, you will see a massive wall of speakers housed in an acoustic baffle (speaker system enclosure).

 

The baffle wall is approximately the same size as the screen, providing a solid, smooth and uninterrupted surface to distribute sound throughout the auditorium. It produces a large sound image and accurately tracks sound elements with the onscreen action. This makes panning shots and off-screen sounds more believable and natural, helping to pull audiences into the storyline. Without a baffle wall, sound is uncontrolled – producing a weak, uneven image.

 

With the baffle wall
 

The baffle wall in a THX Certified Cinema controls the sound behind the screen – projecting a smooth audio experience out to the audience.

 

Without the baffle wall
 

Without the baffle wall, sound is uncontrolled behind the screen – producing a weak sound image that “jumps” across the screen.

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Unique to every THX Certified Cinema is the THX “baffle wall.” If you were to peel away the screen at any THX Certified Cinema, you will see a massive wall of speakers housed in an acoustic baffle (speaker system enclosure).

 

The baffle wall is approximately the same size as the screen, providing a solid, smooth and uninterrupted surface to distribute sound throughout the auditorium. It produces a large sound image and accurately tracks sound elements with the onscreen action. This makes panning shots and off-screen sounds more believable and natural, helping to pull audiences into the storyline. Without a baffle wall, sound is uncontrolled – producing a weak, uneven image.

 

With the baffle wall

 

The baffle wall in a THX Certified Cinema controls the sound behind the screen – projecting a smooth audio experience out to the audience.

 

Without the baffle wall

 

Without the baffle wall, sound is uncontrolled behind the screen – producing a weak sound image that “jumps” across the screen.

 

The baffle wall also loads the speakers to provide a few dB more bass. 

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I was wondering what wings do on speakers or their purpose, or if anyone ever thought about putting them on Jub bass bins. On youtube there is a video named DIY Klipschorn  2, but the speakers look like a Jub clones but  with wings. Even though its coming out of computer speakers, the sound is very interesting.

not sure as you did not provide a link and I did not feel like spending the time searching past this one.

If that is that the video you refered to?

If so the user has what appear to be a set of Jubilee. On is out from the corner the other does not look to have a corner so he is on the left channel using short wings to prevent bass from rolling back around the cabinet and similarly on the right channel since he has no corner there the wings will help to project the low frequencies. Using wings will also help to extend the mouth just a little but mostly here it looks to be for the benefit of additional directionality. This is probably the owner simply making the best of a less than ideal situation. Proper corner placement would be much more effective. (got my coffee now).

 

 

The "wings" look to be about 12" wide, certainly no more than 18".

 

The wavelength of a 500Hz tone is more than 2'. At 40 Hz the wavelength is 28'.

 

I have to wonder what "bass" frequencies one hopes to reflect, reinforce or control directivity with those apparatus.

 

I might be wrong, but wasn't one of the design goals of the Jubilee (as an improvement to the original Klipschorn) to throw the bass more directly into the room instead of along the walls?

 

The person who assembled those contraptions, I'm sure,  "believes" they have made a substantial improvement. The laws of physics speak otherwise.

 

And what about the room? It sucks. No amount of "wing" is going to improve anything in that kind of space.

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And not only that, the guy is so concerned about adding wings to the Jubilee to improve LF response/directivity but look at the long table. No mid of treble reflections from that? Oh wait. That must be a large diffuser. My Bad.

Edited by artto
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That is one experiment, yes. There have been several. That's when I stopped posting, and even then I didn't post everything from that experience. Having the bifurcation separated like that allowed for several experiments that could be applicable here.

Have you designed and built anything?

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Yes.

 

But, you know, it takes too much effort to share it with anyone... ;)

 

Actually...I'll share my latest at some future date, but there are a lot of kinks to work out.  It's a bit complicated--and nothing like I've attempted before.

 

My first experiments occurred before Thiele and Small published their paper - and it was a large acoustic suspension design (15" woofers) using methods later developed into the T/S parameters.  It certainly is nice to have had access to a full woodworking shop growing up (and presently).  Having someone that could help out on setups and design refinements was nice, too. 

 

My father built and tested a full Khorn--the 2-way version of the 1950s with the K-5 horn--that I grew up with when he worked as an assistant professor (SMU EE).  Access to test equipment has always been real advantage, too.  

 

It's nice to have the time available to do these sort of things now :emotion-21:

 

Chris

Edited by Chris A
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  • Klipsch Employees

Unique to every THX Certified Cinema is the THX “baffle wall.” If you were to peel away the screen at any THX Certified Cinema, you will see a massive wall of speakers housed in an acoustic baffle (speaker system enclosure).

 

The baffle wall is approximately the same size as the screen, providing a solid, smooth and uninterrupted surface to distribute sound throughout the auditorium. It produces a large sound image and accurately tracks sound elements with the onscreen action. This makes panning shots and off-screen sounds more believable and natural, helping to pull audiences into the storyline. Without a baffle wall, sound is uncontrolled – producing a weak, uneven image.

 

With the baffle wall

 

The baffle wall in a THX Certified Cinema controls the sound behind the screen – projecting a smooth audio experience out to the audience.

 

Without the baffle wall

 

Without the baffle wall, sound is uncontrolled behind the screen – producing a weak sound image that “jumps” across the screen.

I don't agree. Most of the cinemas going up (dare I say all of the ones I am involved in) do not use a wall and they exhibit excellent imaging and staging. Although the original spec of thx included a wall, it was like most things in cinema to compensate for the current speakers being used. If a horn is designed for half space then it will need a wall. If not then it won't. And since coverage is a strong positive the crossover points are picked while still in the coverage pattern. Lfs that use a single woofer tend to exhibit some increase gain but again that sometimes is not a good thing.
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Unique to every THX Certified Cinema is the THX “baffle wall.” If you were to peel away the screen at any THX Certified Cinema, you will see a massive wall of speakers housed in an acoustic baffle (speaker system enclosure).

 

The baffle wall is approximately the same size as the screen, providing a solid, smooth and uninterrupted surface to distribute sound throughout the auditorium. It produces a large sound image and accurately tracks sound elements with the onscreen action. This makes panning shots and off-screen sounds more believable and natural, helping to pull audiences into the storyline. Without a baffle wall, sound is uncontrolled – producing a weak, uneven image.

 

With the baffle wall

 

The baffle wall in a THX Certified Cinema controls the sound behind the screen – projecting a smooth audio experience out to the audience.

 

Without the baffle wall

 

Without the baffle wall, sound is uncontrolled behind the screen – producing a weak sound image that “jumps” across the screen.

I don't agree. Most of the cinemas going up (dare I say all of the ones I am involved in) do not use a wall and they exhibit excellent imaging and staging. Although the original spec of thx included a wall, it was like most things in cinema to compensate for the current speakers being used. If a horn is designed for half space then it will need a wall. If not then it won't. And since coverage is a strong positive the crossover points are picked while still in the coverage pattern. Lfs that use a single woofer tend to exhibit some increase gain but again that sometimes is not a good thing.

 

 

Yeah, the "wings" -- essentially baffle walls --  I have seen in cinemas were all put in in the 1950s, 1960s, 1970s, surrounding either big Altec 4 woofer horn-loaded designs (Cinerama, and some 35 mm 'scope theaters), or big 4 woofer JBLs (Todd-AO, and other 70mm theaters) that had their front-loaded bass horns embedded in a huge enclosure (with a port) that served as baffle/wings in & of themselves.

 

On the other hand, the San Francisco IMAX at the Sony center has neither wings or a baffle board, and, even with a big subwoofer, the bass is weak sounding, compared to that of the types of cinemas mentioned above.  I'd say the deficit would be in the upper bass region, maybe from 100 to 250 Hz ...

 

Roy, what theaters does Klipsch supply the speakers for?   I've heard that they do Regal, but I don't know if that would be for all in the Regal chain.  Are they horn-loaded?  Are Jubilees being currently installed in theaters? 

 

Some of us (at least I) would like to go to Klipsch equipped theaters to see what the sound is like.  We'll bet it's good.

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  • 9 months later...

post-26262-0-64680000-1466168058_thumb.p

 

Jub wings in blue, and room corner shown behind the bass bin for reference only--since you wouldn't typically have the bass bins in corners if using wings.  I'd guess that the wing extensions need to extend 12-18 inches in front of the bass cabinet.

 

While you're at it, I'd also recommend a "nose" on the center section--like you see on the center of a La Scala bass bin--in order to improve and widen the midbass polars by gradually combining the two horn mouths into one mouth.  Roy has discussed the advantages of adding this.

 

Chris

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