The Jubs convergence point is something like 6 to 8 feet....allowing one to sit rather close to them. The khorns are about 10-15 feet, which I think has more to do with the sound coming out of the sides having enough room to bounce back towards the listening position (the mid bass always sounds lean if you're too far forward).

Mike Lindsey:

Ceilings are 9.5' and are flat.

Mike

DrWho:

The Jubs convergence point is something like 6 to 8 feet....allowing one to sit rather close to them. The khorns are about 10-15 feet, which I think has more to do with the sound coming out of the sides having enough room to bounce back towards the listening position (the mid bass always sounds lean if you're too far forward).

Where did you get this info? What assumptions? 

Bill W.:

seti:

Excellent write up. PWK & Roy hit one out of the ballpark with the Klipschorn Jubilee. Are live bands use the Jubilees to play through?

 

Please post some pics! 

Hi Seti -

Yes we are using the Jubilees for live bands. The word has gotten out and the musicians invite their friends to come and enjoy the performance because they have never sounded better. We booked a regional singer/songwriter who sang for the closing ceremonies of the Salt Lake City Winter Olympics. She enjoyed it so much she has been back to perform twice. 

Cask05:

DrWho:

The Jubs convergence point is something like 6 to 8 feet....allowing one to sit rather close to them. The khorns are about 10-15 feet, which I think has more to do with the sound coming out of the sides having enough room to bounce back towards the listening position (the mid bass always sounds lean if you're too far forward).

Mike,

Where did you get this info? What assumptions?

I used my ears?

Actually, if you want to calculate it...the convergence point is where the polars of the bass bin and the HF section fully overlap. Because the K402 is truly a constant directivity design, and the polars are closely matched at the crossover frequency, the overlap point is going to happen very near the point calculated by using the nominal coverage angles (aka, 90x60 degrees). So from the center of the K402, draw a line that falls at 30 degrees until it intersects with a line rising at about 20 degrees from the bassbin (the bassbin beams a bit more than the 402)...I think you end up about 6 feet away or so.

WIth the Khorn, the polar response of the individual drive sections are changing quite a bit...especially with the bassbin and the top end of the squawker (since it's using collapsed vertical polars to extend its high frequencies). With this in mind, the true convergance point is going to be further away than the nominal advertised polars because you're going to have narrow mismatched polars in the critical crossover bands. Saying it this way makes it sound really negative which isn't really my intention...PWK was thinking about polars with the Khorn too (in fact, he puts it as #3 more important over #4 the  on-axis frequency response)

You gotta be like 10 feet away with the Heresy and about 15 feet away with the lascala. If you ever get the chance, play some music on some speakers outdoors and start walking away from them...there will be a very well defined point where the sound just gels together. The same physics apply in a room, but usually you've got so many reflections that it totally masks whether or not the direct sound from the speaker has converged or not.

And if you're feeling really lazy, just measure the distance between the centers of each of the drivers and then multiply by 10...it seems to yield a ballpark number that coincides with typical speaker dispersion patterns. (It makes sense that taller speakers will require longer distances to converge).

Cask05:

Mike Lindsey:

Ceilings are 9.5' and are flat.

Mike

Wow.

It's Florida! Will this room be big enough?

DrWho:

Cask05:

DrWho:

The Jubs convergence point is something like 6 to 8 feet....allowing one to sit rather close to them. The khorns are about 10-15 feet, which I think has more to do with the sound coming out of the sides having enough room to bounce back towards the listening position (the mid bass always sounds lean if you're too far forward).

Mike,

Where did you get this info? What assumptions?

 

I used my ears?

Actually, if you want to calculate it...the convergence point is where the polars of the bass bin and the HF section fully overlap. Because the K402 is truly a constant directivity design, and the polars are closely matched at the crossover frequency, the overlap point is going to happen very near the point calculated by using the nominal coverage angles (aka, 90x60 degrees). So from the center of the K402, draw a line that falls at 30 degrees until it intersects with a line rising at about 20 degrees from the bassbin (the bassbin beams a bit more than the 402)...I think you end up about 6 feet away or so.

WIth the Khorn, the polar response of the individual drive sections are changing quite a bit...especially with the bassbin and the top end of the squawker (since it's using collapsed vertical polars to extend its high frequencies). With this in mind, the true convergance point is going to be further away than the nominal advertised polars because you're going to have narrow mismatched polars in the critical crossover bands. Saying it this way makes it sound really negative which isn't really my intention...PWK was thinking about polars with the Khorn too (in fact, he puts it as #3 more important over #4 the  on-axis frequency response)

You gotta be like 10 feet away with the Heresy and about 15 feet away with the lascala. If you ever get the chance, play some music on some speakers outdoors and start walking away from them...there will be a very well defined point where the sound just gels together. The same physics apply in a room, but usually you've got so many reflections that it totally masks whether or not the direct sound from the speaker has converged or not.

And if you're feeling really lazy, just measure the distance between the centers of each of the drivers and then multiply by 10...it seems to yield a ballpark number that coincides with typical speaker dispersion patterns. (It makes sense that taller speakers will require longer distances to converge).

I think I get what you are saying.  You are talking about vertical convergence due to driver/horn vertical separation.  I think that you are apparently assuming that the vertical coverage angles of the Jub horn/driver combination is based on geometrical coverage angles at frequencies above the fc of the horns in the vertical dimension of the horn. For direct radiators, etc., the horizontal and vertical coverage responses are more cardioid and otherwise a strong function of frequency.  I believe you are implying that the off-axis response of the vertically separated driver/horn or direct radiator (whatever the case may be) must be relatively balanced in amplitude across the listening spectrum to achieve "convergence".  Is all this tracking with your explanation above?

I do hear some sort of "convergence" as I walk toward my speakers, although I find that when I'm on axis of the K-402, I always seem to feel that I'm not in the convergence zone, alluding to Geddes's white paper posted under http://forums.klipsch.com/forums/p/44621/1000333.aspx#1000333 where he recommends NOT being on axis above 500 Hz. As I have stated, I haven't tilted my K-402 horns down from the factory-supplied positions.  I found that the minimum "convergence" distance apparently changed when I inserted bass traps into my room--it seemed to decrease but I may be sensitive to the relative tonal balance due the mid-to-upper bass (100-300 Hz) room modes with corner-mounted speakers.  Still tracking?

Chris

Wardsweb:

Congratulations on a worthwhile investment. There are few things that feed our souls and when you find one it is truely a good day. By the way, I have version 2 of my reference CD, if you would like a copy. 

 Bill W.

Am I to understand you have these in Sedona now?  I'm only about 4 miles from the intersection of I-17 and the 101.  Not that far.  Post a note if I could visit mabe week after next?  I'd like to have a good excuse to get away from town and work and all that.

DrWho:

The Jubs convergence point is something like 6 to 8 feet

Is this perhaps an actual, technical term?  I've tried to describe in the past how my Khorns sounded noticably better from say 30' away and the Jubilees sound just as good "up close" (probably me standing at 10') as they do from the same 30' I referenced with the Khorns.

I've thus far, attributed it to them being 2 way and the sound coming together faster/closer.  Either way, I was initially let down that they didn't sound "better" at 30', then I realized it's a GOOD thing that this difference isn't there. (cause they have this 'better sound' at 10')

Same thing?  Different?

Coytee:

DrWho:

The Jubs convergence point is something like 6 to 8 feet

Is this perhaps an actual, technical term?  I've tried to describe in the past how my Khorns sounded noticably better from say 30' away and the Jubilees sound just as good "up close" (probably me standing at 10') as they do from the same 30' I referenced with the Khorns.

I've thus far, attributed it to them being 2 way and the sound coming together faster/closer.  Either way, I was initially let down that they didn't sound "better" at 30', then I realized it's a GOOD thing that this difference isn't there. (cause they have this 'better sound' at 10')

Same thing?  Different?

 

Coytee,

One of the reasons why I asked the questions I did was that I am somewhat unsure of the properties of "speaker convergence" without first talking about room acoustics issues.  You might ask why the La Scala and Heresy convergence distance is so long, but that the Jubs are much shorter (unless driver phase correction/delay is the answer to the question).  They (La Scalas and Heresy's) don't look taller than Jubs; in fact they're not taller, they're shorter.  I think first-bounce areas around the speaker have such a great effect on the perception of convergence in any real room using any real source material other than impulsive ones that the concept is more than a little muddy in practice.  If you throw in the fact that the ear begins to not distinguish directionality below about 500 Hz and many speakers lose directionality at the frequency decreases below 500 Hz, then it really gets complicated (including Haas effects). Driver delay may affect the answer also, assuming good polars of the speaker system drivers.

I really would like to know the source of this idea (i.e., "convergence") and where I can read more about it.  I know that there is some sort of convergence that must be present in any non-coaxial multiple-driver loudspeaker system, but I've not seen the term used in context of what Mike B stated above.  My response was an attempt to get onboard with this idea.

(Breathlessly waiting for an answer),

Chris

Cask05:

I am somewhat unsure of the properties of "speaker convergence" without first talking about room acoustics issues

You're heading into water over my head...(this is MAS territory?)

I will say this again...  my Khorns sounded better when I was standing something like 30' away from them (never really measured the distance) than they did when I was in the open ended room with them (as they fired from the corner into the open end, opening up to foyer and dining room)

The Jubilees simply do NOT have this difference in sound and the room has not changed, so it's GOTTA be the speaker somehow?  (my opinion)

Faced with that and Roy's talk of bubbles...  mixed in with Mike explaining some of the benefits of 2 way over 3 way, I came to believe that the melding of the sound so much closer to the speaker themselves had to do with them being 2 way verses the 3 way Khorns I had.  Maybe some time alignment of the drivers has something to do with that also?  (hadn't thought of that until you mentioned it)

Guess we're both, waiting to exhale...

I think maybe Roy needs to conduct a class "Bubbles 101" or "Bubbles for dummies"

Coytee:

 

I will say this again...  my Khorns sounded better

Hmmmmmmmm

Coytee:

Cask05:

I am somewhat unsure of the properties of "speaker convergence" without first talking about room acoustics issues

You're heading into water over my head...(this is MAS territory?) (I hope not...)

I will say this again...  my Khorns sounded better when I was standing something like 30' away from them (never really measured the distance) than they did when I was in the open ended room with them (as they fired from the corner into the open end, opening up to foyer and dining room) (Yes, agreed.)

The Jubilees simply do NOT have this difference in sound and the room has not changed, so it's GOTTA be the speaker somehow?  (my opinion) (Also agreed.)

Faced with that and Roy's talk of bubbles...  mixed in with Mike explaining some of the benefits of 2 way over 3 way, I came to believe that the melding of the sound so much closer to the speaker themselves had to do with them being 2 way verses the 3 way Khorns I had.  Maybe some time alignment of the drivers has something to do with that also?  (hadn't thought of that until you mentioned it) (bubbles maybe are useful concepts for horn speaker theory, but I'm thinking more about diffraction issues or time-of-arrival issues here - you know, remember your high school science labs.)
 

Guess we're both, waiting to exhale... ( I think that we're both in violent agreement...)

I think maybe Roy needs to conduct a class "Bubbles 101" or "Bubbles for dummies" (or just point to something written on the subject of convergence...)