New Klipsch Jubilee speaker

[Travis]

This guy did a nice video, and he is one of the many younger generation who jumped in on this project which is encouraging to see:

And this awesome video by TikToker Derrick Gee helped!

 

[Travis]

Only 5 days left:

 

[DRNNOO]

This is a DIY project I am working on for a Mastering Monitor. I'm waiting/looking for Jubilee measurements at 115db/1m if anyone has them. I'm betting the crossover point won't allow 115db/1m on the Jubilee but measurements don't lie.

 

[Bjorn]

I'm waiting/looking for Jubilee measurements at 115db/1m if anyone has them. I'm betting the crossover point won't allow 115db/1m on the Jubilee but measurements don't lie.

Here's a raw measurement of the K402 horn used in Jubilee with the Celestion AXi2050 driver. 1/12 oct. smoothing at 1 m distance.

This wasn't measured with 2.83V though, but based on Celestions own measurement it's likely the highest sensitivity is around 110 dB. At 200 Hz, the level has dropped with 15 dB. And at 170 Hz (one octave lower than 340 Hz) the level is about 17-18 dB lower. In other words, there should be enough sensitivity here to do 115 dB at 1 m with the crossover at 340 Hz.

The dual 12" in the bass bin shouldn't struggle either with 115 dB with the crossover. The main disadvantage of the folded horn with twin drivers is a response that isn't very linear. We can see that clearly here with the broad cancellation between 200 Hz and 300 Hz and some other unlinearities. This is a measurement of the old Jubilee that was crossed higher FIY.

With a crossover at 340 Hz, the response now is probably more even. A problem using such a low crossover though is the loss of vertical directivity as the K402 horn starts to gradually loose the 60° directivity at 1000 Hz. However, in the Jubilee where the bass bin/folded horn probably doesn't offer a vertical uniform directivity, it's likely that lowering the crossover is a better compromise also in regards to the vertical directivity.

Below is the vertical coverage of the K402. We can see that at 340 Hz (the crossover in today's Jubilee), the directivity has risen to 100-110°.

 

[DRNNOO]

Thank you!! The Axi2050 appears to have its bandwidth optimized for the critical zone. On the horn above in my pic, the response is very smooth in the critical zone, something like 1.5db margin of error with no other eqing but to fix the tilt of the response.

On the above measurement it is best in the critical zone as well.

I agree about the Jube being able to hit 115db.... I almost didn't think I'd mske 200hz except I forgot about the -9db between xo and stereo pairing. For that reason 340hz is likely fine at 115db/1m

I tried raising the xo point but once I got used to the whole vocal range coming from 1 axis point theres no going back. I listen in the nearfield so that likely puts stress on the loudspeaker to perform in the regards of summing between tweet and woof with the lower xo point having the advantage

My ctc spacing, if I put the woofer to the top, is 18.5" which 2 inches shy of a 1/4wl optimal crossing, something that is unheard of, of a horn, unless we talking about synergy horns. The summing at 200hz works well enough that I can put woofer at the floor for the best FR, though the ctc is stretched to about another 4". Only Barry White's talking breaks the illusion lol!

 

[Bjorn]

Here's Radian 950BePB in comparison. Both with Klipsch K402 at 1 m distance and 1/12 oct. smoothing. Radian in red.

Radian 950 had the dip with Klipsch K402 between 700-800 Hz for some reason. We don't see that in our horn with Radian 951.

What's interesting is that the AXi2050 doesn't go very much lower than the Radian in the K402 horn. The distortion is much lower with the Radian already from midrange and sounded also much more open with better details. The comparison was of course conducted with proper EQ of both and level matching.

 

[DRNNOO]

I'm not mad about it, but I did discover that a top shelf compression driver of the 4 inch diaphragm 2" exit variety, can move about as much air as the Axi. I think the Axi has more xmax and lf extension but would need to compare on the same device to know for sure...

If you have thd readings showing what you described, thatd be awesome.

Beryllium is slightly scary... the dust... I have children... experimenting with lf extension... scary....

I do recall reading your thoughts as well, you told me during our brief discussion over the Axi. I think that at this point we are at the top percentage of performance and that the differences are somewhat trivial, then again Be is supposed to be the better material and having Ti keep up, without a coating, thats something to lol

Outside 115db/1m, little voicing, look how dry the decay is.

 

[Bjorn]

I'm not mad about it, but I did discover that a top shelf compression driver of the 4 inch diaphragm 2" exit variety, can move about as much air as the Axi. I think the Axi has more xmax and lf extension but would need to compare on the same device to know for sure...

If you have thd readings showing what you described, thatd be awesome.

Beryllium is slightly scary... the dust... I have children... experimenting with lf extension... scary....

I do recall reading your thoughts as well, you told me during our brief discussion over the Axi. I think that at this point we are at the top percentage of performance and that the differences are somewhat trivial, then again Be is supposed to be the better material and having Ti keep up, without a coating, thats something to lol

Outside 115db/1m, little voicing, look how dry the decay is.

An exit of 2" will generally have higher distortion than a driver with smaller exit. JBL showed us that a long time ago. See the paper "New Optimized Aperture Horns and Low Distortion Drivers", which can be found in the link below.

JBL Professional 2352, 2353, 2354

jblpro.com

What surprised me, was that the distortion with the Radian 951BePB was lower already from part of the midrange (from around 600-700 Hz if I remember correctly). I did a bunch of THD distortion measurement at different levels. Even if I can find them, I may not share them because achieving accurate distortion measurements are difficult and mine can easily be misleading. While I think I saw the overall picture correct when measuring at different levels, the percentage of distortion is likely wrong. It's better to see proffesional distortion measurements here.

But as the paper of JBL shows, distortion is lower with a more rapid flare rate from the driver into the horn, and another benefit is a beamwidth that's constant higher in frequency. Higher mass also normally increases distortion. Even the Radian 951 with alu with a good horn should be an improvement. Or another high quality compression driver with either 1.4" or 1.5" exit.
2" exit isn't something I would recommend unless one plans to use another tweeter. And using a tweeter with big horns isn't exactly trivial.

 

[DRNNOO]

I agree, except I personally have not felt the need for an extra tweeter. My last system used 1" Kevlar tweeter that I really liked. It fell off at 19khz. Maybe that is why I like the Axi's top end? Midrange is everything they say, and 2" exit is supposed to be the better performer in that regard. I was trying to get the lowest XO so that kind of sealed the deal. Also.... can you hear 20khz? At a 2" exit, Hf may be all in the on axis for you. I never intend to be anywhere else so it suits me. Someone once said that the high frequency will be limited to the visibility of the throat walls? That seems to be true my situation, and probably directed at horns from the salmon family

I love seeing measurements but like you say, things can be get distorted. Maybe taken with a grain salt, is best.

 

[Bjorn]

I see no reason why a 2" exit should be better at the midrange.
A lower Xover is something AXi2050 achieves, but with the cost of a lower quality (high-fidelity) of upper midrange and treble. However, the driver never sounds fatiguing. Less resolution is also less revealing, which may very well be preferable to some.

 

[DRNNOO]

Is this something you think you can show in a measurement or is this just subjective listening? A larger Exit size has more LF efficiency, in turn, provides better midrange, through lower excursions per spl.

Considering that the Axi Diaphragm is moving as low as 0.04mm at domestic volumes. That 0.04mm is on the LF of the passband....I find it hard to see that it is going to somehow, not produce the signal accurately. Timbre is the only thing happening at that low of excursion.

Do you have any measurements that show the spectral decay in a waterfall like mine above? It could be possible that the Axi2050 is more accurate than the Beryllium Diaphragm and that people aren't use to such a Dry presentation. Sorta like a person desiring more Room response versus moving towards Anechoic, at some point. The room is distortion, yet we want a certain amount of it, at least. It is possible that a longer decay sounds more pleasurable to your ears, no different then how people choose High Thd Tube amps that color the sound in a way they like, even though essentially, it is added Distortion, and it is less accurate to the signal

 

[Bjorn]

Is this something you think you can show in a measurement or is this just subjective listening? A larger Exit size has more LF efficiency, in turn, provides better midrange, through lower excursions per spl.

Considering that the Axi Diaphragm is moving as low as 0.04mm at domestic volumes. That 0.04mm is on the LF of the passband....I find it hard to see that it is going to somehow, not produce the signal accurately. Timbre is the only thing happening at that low of excursion.

Do you have any measurements that show the spectral decay in a waterfall like mine above? It could be possible that the Axi2050 is more accurate than the Beryllium Diaphragm and that people aren't use to such a Dry presentation. Sorta like a person desiring more Room response versus moving towards Anechoic, at some point. The room is distortion, yet we want a certain amount of it, at least. It is possible that a longer decay sounds more pleasurable to your ears, no different then how people choose High Thd Tube amps that color the sound in a way they like, even though essentially, it is added Distortion, and it is less accurate to the signal

Late reply. In regards to the higher distortion of the Celestion AXi2050 I haven't been able to find those measurements. But Joseph Crowe has measured the driver and also applied IMD measurements. He saw elevating intermodulation distortion.
Some of his writing below about this.

We have excellent results in the midrange between 500Hz-2kHz showing IMD -78dB. However we see a steady climb in IMD starting at 2kHz rising to only -60dB at 15kHz. For comparison’s sake, a recent tweeter tested here had IMD at -68 dB for the same test SPL. An earlier test found here had IMD at -78dB. The Axi2050 does not achieve my target for audiophile sound quality, at least not for the high frequencies.

As we can see from the above results, IMD is -50dB for the 95dB test, and only -40dB for the 105dB test when looking at the treble region. Distortion is only acceptably low in the 500Hz-1kHz region.

I then measured the intermodulation distortion of the complete system. (Includes bass cabinet No.1798). We can see from the above results that the Axi2050 starts out favourable on the 85dB test, however by 95dB the distortion quickly rises well above that of the bass and midrange. By 105dB distortion is almost +15dB higher than the bass (100Hz vs 15kHz).

He saw some trouble in the time domain behaviour:

The above CSD shows multiple small artifacts across the region from 5kHz upwards.

Obviously the horn will play a role though. Personally I didn't experience what he did. He says the following.

The Celestion Axi2050's behavior changed drastically at elevated listening levels. It went from pleasant and musical to somewhat strident in nature at the higher listening level. This is in the context of using the driver for midrange and treble duty. It’s pretty safe to conclude that there are better choices available if needing 500Hz-20kHz coverage for two channel music home audio.

Perhaps I didn't listen loud enough, but I found the driver to sound smooth. For me it was more lacking in clarity and in detail and this made it sound less engaging and realistic. Sort of like listening to a large 2"-4" piston driver without a tweeter.

Here his test:

Celestion Axi2050

In this blog post I test the Celestion Axi2050 compression driver. I test it on my 300Hz Biradial (ES290 No.1670). I began my measuring the impedance sweep which is shown below. The raw on-axis frequency response is shown below. Sensitivity is excellent at 110dB shelving down -5dB at around...

josephcrowe.com

I haven't seen any concluding data that a 2" exit loads lower then a smaller exit if the horn are optimized for both. It may be true, but there are other factors that have much more influence on this. There are compression drivers with 1.4" exit that go very low (100 Hz and 350 Hz). What we do know from JBLs research is that a smaller exit will exhibit lower distortion above a certain frequency and maintain directivity higher in frequency. Going from the Klipsch K402 with the Radian 950BePB (best 2" driver I tested in the horn) to a horn with 1,5" and 1,4" exit (tried both) was a definitive improvement. But since the horns are different, one is comparing other attributes as well.

Personally I'm not in the school of a lower crossover is always better. That's something I have experiemented a lot with different speakers. While I certainly prefer a low crossover and dislike speakers with crossover especially in the presence area, one also has to consider direcitivity and how the speaker interacts with floor and ceiling. That's one of the reasons why I don't believe a synergy/multry entry horn is the way to go. Distortion also comes into play when choosing the optimal crossover.

 

[DRNNOO]

Something is not right about Joseph's comments. The Axi's IMD is better, through out, according to his own measurements! yet he made no negative comments about the RCF, actually saying that
"The RCF ND850 2.0 exceeds my target for sound quality by a wide margin. Subjectively the driver sounds excellent."
vs
"The Axi2050 does not achieve my target for audiophile sound quality, at least not for the high frequencies."

His Burst Decay of the 2 drivers are not comparable as it seems the RCF was gated and the Axi is not.

The Axi has better IMD measurements and The Cumulative Spectral Decay is comparable in HF as well, much better controlled moving towards the horns Cutoff (reflective of the impedance charts)....As well the Axi2050 has a much Smoother response above 10khz....
The disconnect leads me to discredit his comments. As well, the FR is not very nice for the Axi on his horn. Yet the Axi on my horn as smooth as the RCF on his horn.

As well, He left out the 105db IMD measurements for the RCF so I cannot judge the Axi in comparison to a driver that he found to be "excellent"....It sorta reminds me how manufacturers conveniently leave out measurements....Given that the Axi has lower IMD than the Driver he preferred, at levels he did show, if I was a betting man, I'd say IMD performance is still better with the Axi at 105db compared to the RCF.... So "Excellent driver" vs his comments that at 105db the Axi only has acceptable distortion below 1khz would be conflicting, thus taking away credibility, so best to leave that RCF 105dfb measurement out lol.

I think something is right and somehow the horn + Axi is a no go. Could it have to do with Throat issues? I as well have not noted any significant change due to levels, and unlike some, I experiment above "safe" levels for short periods of time.

Regarding the low crossover. I can only speak for myself, as it seems that I am sensitive to the vertical axis of speakers. Having all the vocals on one Axis is definitely desirable. Distortion definitely comes into play when choosing a XO point but the very large horn (36" wide 20" height) I have allows me to stay within Xmax even at 115db/1m down to my 200hz XO. My experience lives mainly in the 1m world so once again, that is my preference.


I still think things are at the top 10% of the performance regarding these drivers. And that one could be happy with many different drivers, meant to compete at the top.

It also should be noted that people should stop comparing drivers that haven't been SPL matched throughout the whole frequency range.... With todays software, that should be an easy target for most well performing drivers.

 

[kipman725]

Here are more measurements of the AXI2050: https://data-bass.ipbhost.com/topic/1381-measurements-from-big-cds-and-horns/

I'm into big horns we have a 3 way horn system that is in progress:
1) Exponential midbass horn 100-400Hz with 15" driver
2) Midrange horn using 2*M200 midrange compression drivers 400-3k
3) Coaxial 4 element tweeter constant curvature array 3k - 20k

From 400Hz directivity is controlled in the horizontal to 90 degrees, I can't recall what frequency the vertical directivity is controlled from but it's nominaly 60 degrees. Underneath all this we are constructing 8 SKRAM 6th order BP subwoofers loaded with B&C 21SW152. Attached image of midbass horns with temporary soundgear orbit 4s and reflex subs.

 

[Sal1950]

Attached image of midbass horns with temporary soundgear orbit 4s and reflex subs.

WOW, how bigs the room?

 

[kipman725]

I think its this room, so 100-150 cap or so:

horns are 1.2m long, 1x0.6m mouth. https://www.diyaudio.com/community/threads/mega-midbass-straight-horn-139db.349105/

 

[Sal1950]

I think its this room, so 100-150 cap or so:

horns are 1.2m long, 1x0.6m mouth. https://www.diyaudio.com/community/threads/mega-midbass-straight-horn-139db.349105/

Dang I'd love to hear them. Where's Seth's Brundle's transport when we need it.
I grew up on Star Trek 1st gen. I thought we'd have this by now.

 

[Godataloss]

I think its this room, so 100-150 cap or so:

horns are 1.2m long, 1x0.6m mouth. https://www.diyaudio.com/community/threads/mega-midbass-straight-horn-139db.349105/

Should have let the sound engineer design the rest of the place.

 

[kipman725]

There out almost every weekend in the UK around the north west and at lots of festivals no bookings outside of the UK so far so if anyone is in the area just send me a message and I'm sure it can be arranged. Yes venue acoustics are typically awful just sheds or concrete boxes mostly, people just want to put loads of speakers in them not understanding spending less on the speakers and more on damping materials would be better, a capacity crowd helps a lot though. Sometimes we bring our own heavy drapes and mattresses for small concrete boxes. Festival tents are much better but have their own ploblems with adjacent stage bleed and too small stages causing feedback and mic bleed issues.

 

[Subohm]

Questions:

Is there a projected price? Will they come in at under 40K the pair?

I'd be interested knowing how the DSP crossover integrates what appears to be a non-horn bass module (from the clip they said it was some kind of 'horn reinforced' bass-reflex...).

Evidently, like La Scala, it doesn't require a corner? But is 'flat' to 18Hz? Hmmm... Low bass has always been somewhat 'different' with horns, and in any case you want the bass to match the 'attack' of the mid and high horn(s), as much as possible. The big Klipsch horns (K and La Scala) roll off naturally, down under; therefore you generally don't get any unnatural bass 'boom'. But you don't get the 'Deathstar Exploding' kick in the gut, either.

DSP? Does it come with microphone and software that 'measures' and adapts to room acoustics?

Finally, is this a 'poor man's' Everest?

View attachment 164943

I can attest that these jubilees are all the hype and like no other speakers.