I started to look at it a few years back. It would be interesting to see if it offers useful compromises in other horns vs venting the back chamber to the external world.
I played with it, haven't built anything with it. From what I saw in my simulations, it was pretty tricky to add useful extension, but it did reduce driver excursion noticeably. Over quite a broad range.
As built, the Klipsch Heritage Jubillee horn path is about one meter (39") long, and the tuning (Fb) around 22Hz, a wavelength ~16 meters (51 feet) long.
It's processing uses ~18dB boost below the horn's 1/4 wavelength of around 87Hz, so it does not appear the horn is contributing to the vent output SPL.
Reducing heat exchange via direct venting to the external air, thereby reducing thermal compression caused by voice coil heating would be an advantage this design lacks.
Appears the "useful compromise" in this design is simply retaining the aesthetics of the previous Jubilees which had no BR ports to augment response and reduce excursion below the horn cutoff.
Art
Many thanks Art - I knew it used EQ. An old Peavey FH1 with 2 cubic feet added via a base, two ports tuned to ~31Hz and some EQ at Fb (DJK's "Vented La Scala" mod) might save some money. A parallel vented "Dean" could look kinda cool.
D-MAN at Klipsch forums had vented back chamber horns - plus something "jam (?) - did you keep any of those plans ?
D-MAN at Klipsch forums had vented back chamber horns - plus something "jam (?) - did you keep any of those plans ?
Here's two patents by Dana Moore ("D-MAN"):
A parallel ported horn
https://patentimages.storage.googleapis.com/79/57/f2/d7a1c44365bc75/US7252176.pdf
Series vented horn
https://patents.google.com/patent/U...moore+dana)&oq=ported+horn+speaker+moore+dana
Dana - IIRC had a "Jamboree" horn. There was something smaller than that I beleive which I can't find anymore -?
James Novak had one of the earlier throat vented horn patents
https://patentimages.storage.googleapis.com/fb/ba/6e/3059c759353ef7/US2900040.pdf
A parallel ported horn
https://patentimages.storage.googleapis.com/79/57/f2/d7a1c44365bc75/US7252176.pdf
Series vented horn
https://patents.google.com/patent/U...moore+dana)&oq=ported+horn+speaker+moore+dana
Dana - IIRC had a "Jamboree" horn. There was something smaller than that I beleive which I can't find anymore -?
James Novak had one of the earlier throat vented horn patents
https://patentimages.storage.googleapis.com/fb/ba/6e/3059c759353ef7/US2900040.pdf
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No, I don't recall seeing any of D-MAN or Dana Moore's patents before looking at your links.
Concepts he claims in the FOLDED HORN ENCLOSURE WITH INTER-CHANNEL REFLEX-PORTING (you called series vented horn) patent are flawed:
"each port or a combination thereof could optionally be tuned to different resonant frequencies in order to achieve a wider resonant response as desired."
Multiple different length ports combine to a single Fb (box tuning).
The different length port internal pipe resonance each would be different, so the upper midrange peaks and dips they cause would be distributed over a wider frequency band.
He also claims:
"Venting reflex ports into a horn channel would eliminate the well-known negative “chuffing" effects associated with ducted ports...Additionally, by using the same horn channel, the phase response between frequencies would be better retained and presented to the audience in a cohesive manner. In addition, the dispersion pattern would be controlled by the horn structure."
The horn structure is not large enough to control the vent output's dispersion pattern, nor is there any reason to expect phase response between frequencies would be "better retained", or the horn channel would eliminate "chuffing".
Patents are fun...
That Novak horn looks like it would fit well with a Sputnik chandelier and space age/mid century vintage lounge chair 🥰🤭
Only missing the chandelier if you look hard.
Personally, I think Art about nailed it. Probably some other market-based reasons for the choice. Haven't thought through how much horn could really fit the same space and what it'd do, but fixing the delay would have to happen anyway plus probably some boost. Maybe it protects itself below unloading better (?). Haven't looked that hard. Fred whaddya thinking to do or just curious? I can hack-up a 16-bit Akabak model for you to play with if you'd like, it just doesn't seem worth it. To my eye, the chief values are shorter path than LF horn (valueless with processing) and the radiation resistance/better matching...plus it's yunno PWK's lineage so it Has to be a horn-looking thing (but I'm sure Roy has a half-dozen other reasons no one will ever know). IMO, a Dean (bottom) is still an interesting thing on its own merit if a person has corners, but the world doesn't seem to make C-15W's...or houses that accept Deans anymore. Architects/builders keep destroying perfectly good corners with doors and windows.
Personally, I think Art about nailed it. Probably some other market-based reasons for the choice. Haven't thought through how much horn could really fit the same space and what it'd do, but fixing the delay would have to happen anyway plus probably some boost. Maybe it protects itself below unloading better (?). Haven't looked that hard. Fred whaddya thinking to do or just curious? I can hack-up a 16-bit Akabak model for you to play with if you'd like, it just doesn't seem worth it. To my eye, the chief values are shorter path than LF horn (valueless with processing) and the radiation resistance/better matching...plus it's yunno PWK's lineage so it Has to be a horn-looking thing (but I'm sure Roy has a half-dozen other reasons no one will ever know). IMO, a Dean (bottom) is still an interesting thing on its own merit if a person has corners, but the world doesn't seem to make C-15W's...or houses that accept Deans anymore. Architects/builders keep destroying perfectly good corners with doors and windows.
Attachments
Ha, that's right!
David Mcbean has already indicated how to sim a reflex port firing into the same horn. I found it hard to create any meaningful SPL addition with the configuration, but it did lower excursion quite noticeably. So more headroom for EQ to a low Fc, I guess.
I had a pair of LaScala bass horns with Altec drivers way back. I bought them from Bert Doppenberg of BD-Design and used them with a passive line level filter he advised. I don't remember exactly its values and slopes, but it was two low pass filters. One at about 60 Hz and the other at 110 Hz, essentially the one at 60 Hz creating a less steep bass roll-off to complement room gain, and the one at 110 Hz taking over where room gain ended. I later dropped the lower filter to 45 Hz. It sounded really good. The horn and room worked very well together.
Obviously that LaScala bass horn setup relied on the short horn to give dynamic upper bass, the sealed chamber to have some response below the horn's FC, room gain, and passive EQ. I don't understand why the heritage jubilee has a shorter horn length than an old Khorn. And I understand even less why it has more cone area and more volume than my LaScalas and it still needs reflex ports and 18dB boost to get bass out of that thing.
But PWK was involved in development of the original Jubilee and they also worked on reflex ports firing into the horn. So there could be merit that I'm missing. The principle is also used in that cinema horn sub. I'm trying to keep an open mind here. But it still feels like probably a Khorn bass horn, or the original Jubilee, with a smaller amount of EQ and room gain, would produce a similarly low cutoff with fewer tricks and amplifier power.
David Mcbean has already indicated how to sim a reflex port firing into the same horn. I found it hard to create any meaningful SPL addition with the configuration, but it did lower excursion quite noticeably. So more headroom for EQ to a low Fc, I guess.
I had a pair of LaScala bass horns with Altec drivers way back. I bought them from Bert Doppenberg of BD-Design and used them with a passive line level filter he advised. I don't remember exactly its values and slopes, but it was two low pass filters. One at about 60 Hz and the other at 110 Hz, essentially the one at 60 Hz creating a less steep bass roll-off to complement room gain, and the one at 110 Hz taking over where room gain ended. I later dropped the lower filter to 45 Hz. It sounded really good. The horn and room worked very well together.
Obviously that LaScala bass horn setup relied on the short horn to give dynamic upper bass, the sealed chamber to have some response below the horn's FC, room gain, and passive EQ. I don't understand why the heritage jubilee has a shorter horn length than an old Khorn. And I understand even less why it has more cone area and more volume than my LaScalas and it still needs reflex ports and 18dB boost to get bass out of that thing.
But PWK was involved in development of the original Jubilee and they also worked on reflex ports firing into the horn. So there could be merit that I'm missing. The principle is also used in that cinema horn sub. I'm trying to keep an open mind here. But it still feels like probably a Khorn bass horn, or the original Jubilee, with a smaller amount of EQ and room gain, would produce a similarly low cutoff with fewer tricks and amplifier power.
just curous to see where it might work to advantage - I'm a KARLSON Man anyhow(one our of maybe 3) and those BP delites come before horns as I'm crammed into a little 10x50 foot trailer with two people who don't like speaker cabinets nor what I think of as "music".. For a small space a 3-way Karlson stack plus subwoofer could suffice. I'd like to do a KUBE18 to go under the K8mmmmic and K-tube - but won't fit in shelf under a tv. A KUBE15 "would" I'd to keep around 100dB sesnsitive to drive with cheap class D and passive crossover. My KUBE12 sounds prety good in the 3 way stack with a generic xover Also god as helper woofer with $40 Kinter 2.1 3118 amp and K3.5 with 3fe25 at nominal 180Hz cross point.
The old RJ is kinda a hornless thorat vented horn. (adn a ery good way to do things as its cavity is so small as not to be of a mjor concern in teh woofe rto midrange range) - I'll have to lookd at nornresp and see if a horn can be added to an RJ. -?
The old RJ is kinda a hornless thorat vented horn. (adn a ery good way to do things as its cavity is so small as not to be of a mjor concern in teh woofe rto midrange range) - I'll have to lookd at nornresp and see if a horn can be added to an RJ. -?
Where did David show how to vent the port into the horn ? I'd imagine one could male a new access door for a K-horn - mount the ports on that door then boost @ ~Fb I've got a nitemare contrast problem in my pc - tv where the cursor annot bee seen -takes 100x longer to do anyting then if cold see
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It can be modeled as a "Horn-Loaded Vented-Box Enclosure With Port Exit Located Inside Horn Mouth", using the tapped horn option, as described in the Hornresp Help file.
https://www.diyaudio.com/community/threads/hornresp.119854/page-218#post-3899207
It was also mentioned in #13 in this thread you were a part of:
https://www.diyaudio.com/community/threads/10-top-design-open-discussion.320677/
I don't know if there have been changes since then.
https://www.diyaudio.com/community/threads/hornresp.119854/page-218#post-3899207
It was also mentioned in #13 in this thread you were a part of:
https://www.diyaudio.com/community/threads/10-top-design-open-discussion.320677/
I don't know if there have been changes since then.
Where did David show how to vent the port into the horn ? I'd imagine one could male a new access door for a K-horn - mount the ports on that door then boost @ ~Fb I've got a nitemare contrast problem in my pc - tv where the cursor annot bee seen -takes 100x longer to do anyting then if cold see
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You're getting as bad as me, man 🙂 We can't remember anything but I know we did this a few times somewhere.
TH1 with the 1st two segments 0.1 long. Seg 3 is backwards to turn entry, seg 4 out to mouth. The first one misfired on the throat, the second one was a correction.
Start here: https://www.diyaudio.com/community/threads/hornresp.119854/post-6779341
Stop here: https://www.diyaudio.com/community/threads/hornresp.119854/post-6783145
Could morph RJ-ey, if 3 & 4 shortened, and 1 & 2 grew a little. Never built or heard an RJ. Must be K-like, sounding?
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You're getting as bad as me, man 🙂 We can't remember anything but I know we did this a few times somewhere.
TH1 with the 1st two segments 0.1 long. Seg 3 is backwards to turn entry, seg 4 out to mouth. The first one misfired on the throat, the second one was a correction.
Start here: https://www.diyaudio.com/community/threads/hornresp.119854/post-6779341
Stop here: https://www.diyaudio.com/community/threads/hornresp.119854/post-6783145
Could morph RJ-ey, if 3 & 4 shortened, and 1 & 2 grew a little. Never built or heard an RJ. Must be K-like, sounding?
For what it's worth, a good friend of mine installed a pair of Jubilee's around Christmas. I helped a little. Finally ending up running them with a pair of Bryston 4B cubed amps. He does not need the power, it is the quality and lack of system noise (they are 11 dB/watt).
I'll say one thing. I wish I could afford a pair. They are the best speaker system I have ever heard anywhere at any price. Realistic doesn't begin to describe them. The bass? It goes low enough to move things. I sold speakers in the 1970's and designed systems for the first 10 years of my career using T/S parameters early.
Anyway, what they are doing really works and works very well up past concert levels. Just amazing.
-Chris
I'll say one thing. I wish I could afford a pair. They are the best speaker system I have ever heard anywhere at any price. Realistic doesn't begin to describe them. The bass? It goes low enough to move things. I sold speakers in the 1970's and designed systems for the first 10 years of my career using T/S parameters early.
Anyway, what they are doing really works and works very well up past concert levels. Just amazing.
-Chris
That is all probably true - but even they don't escape being horn loaded only to the mid 80's and requiring significant boost at fb - which kinda negates the 111dB one watt figure. A test would be to see how they do with a SET45 or 2a3 SET smp. And #35,000 is a fair chunk of change for some folks.
I think these days a diy-er with carpentry skills could make a pretty good horn rig - not stellar but say as good as modern La Scala for $1000 a pair - and if wanted , incorporate a vented back chamber..
It would be interesting to see for a given bulk what can be done with a vented back chamber to the external world vs one ported into the horn's throat. - Say like a BP6 parallel vs BP6 series situation.
The RJ box does not sound like a Karlson. It's basically devoid of cavity resonance and measures "smooth" Its a very good way to do vented boxes.
I think these days a diy-er with carpentry skills could make a pretty good horn rig - not stellar but say as good as modern La Scala for $1000 a pair - and if wanted , incorporate a vented back chamber..
It would be interesting to see for a given bulk what can be done with a vented back chamber to the external world vs one ported into the horn's throat. - Say like a BP6 parallel vs BP6 series situation.
The RJ box does not sound like a Karlson. It's basically devoid of cavity resonance and measures "smooth" Its a very good way to do vented boxes.
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These things are so revealing, you really do not want to go near them with a SET anything. Why on earth would you do that? The background noise would be extremely annoying! We could easily hear a pair of Nakamichi PA-5II amplifiers. The PA-7II was better. We ran to above concert levels with the PA-5II's and were nowhere near clipping. The Bryston amps would simply end any drivers connected to them if they required that much power.
Honestly, distortion matters. The tractrix horns are so darned clean, if any of the electronics are misbehaving you'll hear it.
I'm using a pair of Klipsch THX 6000 on the bench, and RP-280f in the bedroom, PSB Stratus Gold (original) in the main system. The Tractrix horns sound like domes and do not beam, plus they have been measured to be flat by two people using calibrated mics.
As for the efficiency at fB, that isn't what you hear. You hear the average broadband, you notice the bass kicks and such. There were zero problems using the smallest amplifiers at the loudest levels we subjected ourselves to. I wasn't used to getting kicked in the gut, and I was authorized warranty for Klipsch and worked with the LaScala and Belle along with the others. Back then the crazies were hitting them with Carver PM 1.5 amplifiers (and burning the woofers out). I was also warranty for Carver then. No, I didn't sell anything.
Anyway, you can't call the Jubilee "legacy" at all. These are a totally new animal, more like the RP-7III and other new systems. Just awesome.
Honestly, distortion matters. The tractrix horns are so darned clean, if any of the electronics are misbehaving you'll hear it.
I'm using a pair of Klipsch THX 6000 on the bench, and RP-280f in the bedroom, PSB Stratus Gold (original) in the main system. The Tractrix horns sound like domes and do not beam, plus they have been measured to be flat by two people using calibrated mics.
As for the efficiency at fB, that isn't what you hear. You hear the average broadband, you notice the bass kicks and such. There were zero problems using the smallest amplifiers at the loudest levels we subjected ourselves to. I wasn't used to getting kicked in the gut, and I was authorized warranty for Klipsch and worked with the LaScala and Belle along with the others. Back then the crazies were hitting them with Carver PM 1.5 amplifiers (and burning the woofers out). I was also warranty for Carver then. No, I didn't sell anything.
Anyway, you can't call the Jubilee "legacy" at all. These are a totally new animal, more like the RP-7III and other new systems. Just awesome.