alternative designs- why go jubilee?

[ZAKO]

Seti.....Why drag your body over all that broken glass.... Get the Jubilee bass bins. You wont regret it......Im too old now to start over...Your still young...Disposible income will be easier to find & you will be ahead of the hobby. The only hurdle is the big bass bins. You can probably run & jump over them (financially)....I can barely carry the ladder anymore. I said earlier about the Jubs. It will be the young turks to carry the momentom forward with the Jubs....As I did with the earley Khorns.

[JBryan]

I'm really enjoying this thread - it has a lot of meat to it. I remember reading that one of the reasons for re-designing the bass bin was that PWK wanted to address the distortions in the upper bass region. The Khorn's bass bin is being pushed a bit beyond its limits to meet the 400Hz xover point and the frequency waves above say, 250Hz become increasingly distorted as they make their way through the folded horn. Does that sound familiar to anyone?

What I like about the 2-way design is that it not only simplifies the xover but also creates more cohesion by reducing time-alignment and frequency overlap problems between the drivers. The result should be a more defined image.

[seti]

Seti.....Why drag your body over all that broken glass.... Get the Jubilee bass bins. You wont regret it......Im too old now to start over...Your still young...Disposible income will be easier to find & you will be ahead of the hobby.  The only hurdle is the big bass bins. You can probably run & jump over them (financially)....I can barely carry the ladder anymore. I said earlier about the Jubs. It will be the young turks to carry the momentom forward with the Jubs....As I did with the earley Khorns.

I guess part of me wants to do it as a progression through my favorite speakers to the ultimate. I can't go without tunes that long and for me to purchase the jubilees the progression would be xovers, bass bins, hf horns and drivers but not necessarily in that order. Maron thanks for the encouragement and I will get there in the next couple years perhaps sooner if I prostitute myself properly : )

[chops]

I'm almost affraid to get involved in this thread, but I'm going to take a jab at it anyway... Just keep in mind, I'm pretty good with this kind of stuff, but I just don't know all of the technical jargon that some of you do. LOL []

As far as the quality of low-end bass of any of these horns are concerned (fat, light, loose, smeared, etc, etc...), I have not seen mentioned anywhere anything about the kinds of amplification being used when these assessments were made.

To my understanding, not only is it a matter of the amp being SS or tube, but the quality of the power supply, the topology, the components, the power output, etc, etc used to make up said amplifier. All of these key factors plus others in and of themselves also play a roll on how bass sounds. All amplifiers lean either towards fat or lean sounding, slow and sloppy or fast and tight sounding, so that too has to be factored into what you are hearing coming from your Khorn, Jub, LS bass bins. One amp can make a speaker sound lean whereas another amp can make that same speaker sound fat.

In the ideal world, the electronics should add nothing to the sound, then we would only be limited to the limits of the loudspeaker itself (and of course the room they are in). But even then, you still have to factor in personal taste. Fat and sloppy bass to me may sound natural and detailed to someone else, and lean and thin bass to you may sound open and airy to the next person. It's a never-ending battle.

**********

Now as far as the limited upper-range of the Khorn, if I understand correctly, it is NOT a function of the driver, but of the horn itself. So no matter what driver you install in a "stock" Khorn, you're still going to be faced with an acoustic rolloff of around 400Hz or so no matter what, right?

If that's the case, then I would only imagine that modifications would have to be made to the original Khorn, or an entirely new design would have to be born (a.k.a. - the Jub and DM's V2).

**********

The discussion of 12" vs 15" vs 18", single, dual, whatever, there are pros and cons there as well. I think the same rules still apply to those particular size drivers no matter how many are being used of each, it's just that those rules come into play at much higher power and SPL levels than they would with a single driver.

IOW, if you have 1% THD from a single 12" driver at Xmax, then you will have 2% THD from dual 12" drivers at Xmax. Granted this would be reached at double the power and SPL output.

Correct me if I'm wrong with this, but if you're running dual drivers and you reach Xmax again, then wouldn't you be hearing double the amount of distortion because you are now hearing twice the amount of distortion due to running dual drivers?!

Of course, all of this is a moot point when considering say 100dB with a single driver vs 100dB with dual drivers of same make and model.

And once you get into the discussion of 2x12" vs 1x15" or 2x15" vs 1x18", there are some things to consider there as well...

If you look at any decent brand and model driver, say the Eminence Definimax series, they make them in 12", 15" and 18". If you look at their specs, they have nearly identical motor structures (109oz magnet, 4" VC, 8 ohms). However, their Re, Le, Pe and SPL change slightly due to the added mass and size of the cones(I assume). Also, the Xmax changes slightly between models, not due to limitations of the spider, but because of the size limitations of the cloth surrounds between the edge of the cone and basket. If you look at all three drivers on PartsExpress's site, you can clearly see that there is physically more space between the edge of the cone and basket on the 15" driver compared to the other two drivers, allowing the surround to be slightly larger, hence why the 15" has the most Xmax of the bunch.

So getting back to my original point about the motor structures, wouldn't you think that running dual 12's would out-perform a single 15", NOT only because of the 28% increase of surface area, but simply because of the 100% increase in motor strength?!

**********

The way I see it, a bass horn is similar to a bandpass subwoofer enclosure; it has freq range limitations on both ends of the spectrum due to size issues. If you increase horn length/size, you extend deeper, but lose more topend. If you decrease length/size, you lose bass extension but gain topend. But I guess that also isn't totally correct either considering what kind of horn you design, unless it's a folded horn.

Also, (me assuming things again), should it not matter what type, size or quanity of driver used that would determine the freq range of a given horn? Isn't it totally up to the length/size of the horn that determines the freq range? Kind of like a governor on an engine, it doesn't matter is the engine has 100hp or 350hp, if it's governed to 65mph, it's ONLY going to do 65mph no matter what.

Like Dr Who says, "It's all about compromise".

If you want lower bass extension, you have to design a physically larger folded horn, and if you want better topend extension, you need to design a somewhat smaller horn, or go with a completely different horn design altogether. Maybe a bass reflex/horn hybrid, something like the Altec A7 which will get you the topend you want along with decent bass extension, however with a larger footprint. It has been around nearly as long as the Khorn (early 1950's) and every bit as successful, so they must be doing something right.

Anyway, that's my take on it. []

[Duke Spinner]

I

IOW, if you have 1% THD from a single 12" driver at Xmax, then you will have 2% THD from dual 12" drivers at Xmax.

driver Distortion .component's...

iare not Additive

[Horatio]

I'm not so much replying to this specific post as to the thread.

When I originally made the first post opening this thread, my question/challenge was to think outside the box, in terms of how we approach horn-loaded systems. In particular, I offered up, along the way, two concepts (sub, Khorn/Jub style, with 'satellites' that were two way, and another concept: cylindrical wavefront/omni system). We have seen subsequent discussions debate the relative merits of Khorns/Jubs/Scoops/etc., and alot of discussion on folding. It sort of reminds me of reading the literature of the 1950's again, but with a modern twist. We have found pretty much all the basic ways to fold a horn, and to fit one into a corner. We have some pretty good designs for this. We are treading familiar ground, again and again.

To go back to the original question: what's next on the horizon? I submit that we have tapped out the potential in our present methodology, and our improvements are incremental.

One thing that has come out in this thread is the very present need for measurements. We have designers on this forum who design and design, and we think we are improving, but we rarely have measurements to support this (although we DO have the very important golden ear'd impressions). Somewhere along the thread I picked up a comment about PWK, and his affinity for 'rough curves'. This is a great comment, because it sheds light on our problem: first, we need to measure. Second, we must decide WHAT to measure, and third, we need to figure out what to do when something measures well, but sound's bad, or measures poorly ('rough curves') but sound's great. If it measures good but sound's bad, we're measuring the wrong thing. An example: I saw someone post about a Huygens reflector design style in their folding geometry. That's a conceptually interesting thing- what is its impact? One of the cool things about the Jub style of folding is that (in addition to being a walk in the park to build, compared to a Khorn), it ought to lend itself to direct measurement of the acoustic wavefront (I don't know quite how this'd be done, but, you have direct access to the path in this design, and our measurement technology today is substantially more capable). It would be really interesting to make measurements of just what DOES happen to the wavefront as it propagates through. And the question of whether Huygenian reflectors help or not could be directly answered, among other things. Lacking direct measurement, surely we have indirect measurements that could make such comparisons (e.g., the standards, frequency response, IM distortion, and so on) of the effect of subtle changes to the folding geometry. Indirect measurements ultimately, though, will not inarguably answer the question of what it happening to the wavefront.

But, all this discussion of corner foldings and relative merits...it is rather like the fellow who lost his wallet in the alley, but is hunting for it by the street light, because it's brighter there. We can continue to debate the merits of various foldings and driver combinations and so on, but the original question still stands lurking in the darkness of the alleyway: what will the 'next big thing' be (unfettered by our predisposition to work with what we have and know...)? When I looked at this a lonnnnggg time ago, it was apparent to me that the polar radiation patterns were much more important than we had thought. I ask again: if we are reproducing music that is recorded by a transducer with specific properties, including a very defined polar response, ought we not be also attempting to design transducers that play back with these same kinds of properties?

<playing the cantankerous crank, here>

[D-MAN]

I didn't hear a resounding "yes"...

it's not quite convincing?

Brings up another point about things in general, once they get so good, or the performance is at such a level, there are only differences, not a complete re-ordering of the universe! It's not that one totally eclipses the other, rather it's a lateral shift, more akin to personal preference than a striking difference in performance.

DM

DM

I'm not sure what your point is here as far as: I didn't hear a resounding "yes"... it's not quite convincing?

Just to make my personel opinion clear for you. The Jubilee I bought (this includes the K402/K69A also) is not just a lateral shift or just a different sound to me. It was a clear and meaningfull improvement in Sound Reproduction over my KHorns! and it was important enough to me to make every effort to obtain the Jubilee since Life is short and I wanted to enjoy them while I can.

What I wouldn't do is be irresponseable enough to talk someone else into them when they say they really like what they have now.

mike tn

Mike, granted. However, having and sharing an opinion, is NOT irresponsible.

Why won't anyone answer the question: Does the Jubilee "Kick" or not? Yes or no.

Dana

[Coytee]

In my room at my house, with my electronics, YES, the Jubilees OUTKICK the Khorn by a noticable margin.

They do it at lower levels, they do it at higher levels (db's)

They sound more cohesive closer in and further away (the Khorns sounded better to me if you were 20' back & gave the sound some time to 'meld together'... the sound melds together much quicker with the Jubilees)

[]

Now... when can we expect your arrival so you can hear them for yourself?

Even better idea... perhaps I can get my tape recorder out and simply record them & mail the tape to you?

[6]

[Coytee]

Maybe since Mark1011 heard the Khorns in the same room he heard the Jubilees, he too can offer his opinion (of which I've not noticed yet if he has)

Sending him an email to this thread now.

[jwc]

Well...I was there. I'll chime in.

Dana...are you meaning like...."bass drum kick"?

At any rate. I feel like many are tired of my description how the Jubilee bass bin sounds. But here it is again.

Mark1101 has Richards Khorns in his house right now and was with me at Richards to hear his jubs in the home. Mark got to hear richards past Khorns in the same corners that richards new jubs sit right now.

To start with...the Jub bass bin and the K402 horn are outstanding. Richard has a wonderful stereo setup.

The Jub bass bin kicks you in the chest....not just bass around the room. It isn't bass in the chest in the 30Hz range...but probably hard in the upper 40's and 80-100's. The 80-100's in my limited experience seems to be something my ear loves. If I were to EQ a stereo to taste w/o an RTA, I would probably have this range turned up too high. I also describe the jub bass bin sound as having a slight "boom". It is a good "boom'. I heard that same sound at Richard's and at Hope.

Would I say a Jub "kicks" more than a khorn? I can't answer that. I also reserve to say that I am in need of a demo of Khorns in a proper placement in corners and in the right room.

jc

[chops]

I

IOW, if you have 1% THD from a single 12" driver at Xmax, then you will have 2% THD from dual 12" drivers at Xmax.

driver Distortion .component's...

iare not Additive

Sometimes I have absolutely no clue what you're saying...

If you're implying that the distorsion from both drivers don't add up to louder distorsion than from a single driver, then how is that so?

Distorsion is sound too. If there are two sources of distorsion, that distorsion has to be louder from both drivers combined than just from a single driver. And if that distorsion is louder, then wouldn't be measured as "more" distorsion?

**********

To get back to the original question that started this thread "to think outside the box" and "what's next on the horizon?", I think that might be a little bit on the impossible side when confined to the interior of a home.

To do something like that, you would still need a fairly large driver for the bass section, you would need very large 360* horn lenses for the bass and topend, and enough space between the surrounding walls and large speaker arrays to get anything good out of them.

When I had my Maggies and Definitive Technologies, and even when I used to set up Maggies, Quad and Martin Logan and any other kind of bipole/dipole loudspeakers in a client's house, they always sounded best when placed a few feet (at least) in from the side and back walls. A speaker design like that needs room to breath, and being that a 360* fullrange horn system would be the size of a small house, it would be highly impracticle for home use.

[Coytee]

Chops,

I don't know if it's the same or less. My understanding from a brief email from Roy was, using 2 drivers (what ever their distortion may be) will mean in this case, 1/2 LESS movement of each driver to obtain the same output. Since the drivers move LESS to get the output, there is less distortion.

Though the specifics of that may not be exact, the general point of it is what I understood him to be saying.

To put another way,

If you have 500 bose 4" drivers, each playing at 50 db's, would you have 50 TOTAL db's of sound in the room, or 25,000 db's?

(I fear that's not apples/apples comparison)

[chops]

Chops,

I don't know if it's the same or less. My understanding from a brief email from Roy was, using 2 drivers (what ever their distortion may be) will mean in this case, 1/2 LESS movement of each driver to obtain the same output. Since the drivers move LESS to get the output, there is less distortion.

Though the specifics of that may not be exact, the general point of it is what I understood him to be saying.

To put another way,

If you have 500 bose 4" drivers, each playing at 50 db's, would you have 50 TOTAL db's of sound in the room, or 25,000 db's?

(I fear that's not apples/apples comparison)

Of course I realise that for a given SPL, but I was referring to when you reach Xmax on the drivers. Xmax is Xmax, it doesn't matter how many drivers there are.

Does that make a little more sence from me? LOL

[mark1101]

I guess I could contribute on this too. I did hear the Khorns at Richard's and my house, and then the jubilees back at Richards.

I still have not heard the Khorns I have make anywhere's near the bass I heard come out of the same speakers at Richard's house. I attribute the vast difference to me using 60 watt tube power, and Richard using over 100 watts of s/s power. Yeah, the rooms are different and all, but the sound difference I'm talking about is pretty large.

I have a s/s amp setup in an adjacent room in my basement running my LaScalas and that system too puts out way more bass than my Khorns running on tubes. It's nowhere's near as musical, but it puts out bass.

But.....the Khorns go way lower. Lower is the key here in my opinion. I could simply add a powerful s/s amp and change the whole game....and still have it go lower. I'm pretty sure of that.

I also think it is not fair to compare the Jubilee to a Khorn. You are talking about a speaker system designed for a theater compared to a home speaker. The Jubilee has a much harder hitting bigger sounding bottom end...way more bass output. It doesn't seem to be even close from what I heard. The jubilee will simply bowl you over without much effort.

But...I hear my Khorns play lower in my house. I'm sure of that.

I gave Richard's Jubilees a rave review somewhere in a thread on here, and I also said in the same thread I wouldn't be selling my Khorns. I still feel exactly the same way.

Two excellent speaker systems that sound different and were built to sound different....and too many variables in my travels and between our houses to make much more of a comparison.

[seti]

I guess I could contribute on this too.  I did hear the Khorns at Richard's and my house, and then the jubilees back at Richards.

I still have not heard the Khorns I have make anywhere's near the bass I heard come out of the same speakers at Richard's house.  I attribute the vast difference to me using 60 watt tube power, and Richard using over 100 watts of s/s power.  Yeah, the rooms are different and all, but the sound difference I'm talking about is pretty large.

I have a s/s amp setup in an adjacent room in my basement running my LaScalas and that system too puts out way more bass than my Khorns running on tubes.  It's nowhere's near as musical, but it puts out bass.

But.....the Khorns go way lower.  Lower is the key here in my opinion.  I could simply add a powerful s/s amp and change the whole game....and still have it go lower.  I'm pretty sure of that.

I also think it is not fair to compare the Jubilee to a Khorn.  You are talking about a speaker system designed for a theater compared to a home speaker.  The Jubilee has a much harder hitting bigger sounding bottom end...way more bass output.  It doesn't seem to be even close from what I heard.  The jubilee will simply bowl you over without much effort.

But...I hear my Khorns play lower in my house.  I'm sure of that.

I gave Richard's Jubilees a rave review somewhere in a thread on here, and I also said in the same thread I wouldn't be selling my Khorns.  I still feel exactly the same way.

Two excellent speaker systems that sound different and were built to sound different....and too many variables in my travels and between our houses to make much more of a comparison.

If you look at the Jubilee PWK is pictured with featuring the veneered front and horn this was meant to be a home speaker or at least a version of it was. At some point during our time at Hope this year it was mentioned that PWK considered replacing the Khorn with the Jubilee. If I remember correctly PWK just got too sick to be able to complete the Jubilee as a consumer product but at least it made it to the pro cinema line.

[jwc]

I again don't think the Khorn or any of the heritage speakers need to be in the same class as the jubilee. That cinema setup has no noticeable sound characteristic of Heritage stuff. Is sounds awesome and sounds different. There are a lot of variables that make this conclusion.

If the Khorn was to be "replaced" with the Jub......

[Coytee]

I understood the story to be the Jubilee was supposed to be the next generation Klipschorn BUT, when they finished it, PWK felt it was significantly superior to the Khorn as to not be an improvement but a quantum leap forward. Because of that, he then decided it needed its own designation other than Khorn.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

I was looking for the email to back me up but my memory says the above commentary was from <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Roy. I cant find the backup to verify.

The below IS an email from Roy with his words being in blue. I was wondering if the Jubilee would have as quick bass as we talk about the Khorn having. It was the last of several questions I put to him.

Would these have as "quick" of bass as the Khorns do? quick is mostly related to how well the driver is horn loaded and some to mass of the driver. the 12 in the jub has more mass than the 15 in the khorn but there are two 12's and they don't have to move as much. the horn expansion on the jub is much more known and controlled and loads better. the distortion data show this. where the khorn is 3% to 1% the jub is 1% to .3%.

[Duke Spinner]

I

IOW, if you have 1% THD from a single 12" driver at Xmax, then you will have 2% THD from dual 12" drivers at Xmax.

driver Distortion .component's...

iare not Additive

Sometimes I have absolutely no clue what you're saying...

If you're implying that the distorsion from both drivers don't add up to louder distorsion than from a single driver, then how is that so?

Distorsion is sound too. If there are two sources of distorsion, that distorsion has to be louder from both drivers combined than just from a single driver. And if that distorsion is louder, then wouldn't be measured as "more" distorsion?

**********

Chopsy .....

Noooooo..... Polite way to say this

ifn' ya wanna Debate these answers

YOU need to start from a Genuine landed technical background....

because what you propose is happening here ....Re: doubled distortion component

is laughable to a first year Engineering student

[Duke Spinner]

yer just not gettin' the drift, Chopsy ....

[chops]

Chopsy .....

Noooooo..... Polite way to say this

ifn' ya wanna Debate these answers

YOU need to start from a Genuine landed technical background....

because what you propose is happening here ....Re: doubled distortion component

is laughable to a first year Engineering student

Well that's all fine and dandy, but doesn't explain anything.

So Dukey, do tell me what's going on then. I'm not trying to start a fight or get into name-calling, I'm just trying to find out information.

Maybe I'm not explaining myself, I don't know. What I'm trying to get at is if you have 2 cones distorting instead of just one cone distorting, then the distorsion should be twice as loud, no/yes?!

And I am referring to reaching the limits of the drivers, whether it be one driver or two.

2 hands clapping is NOT as loud as 2000 hands clapping.