New to horns here. I have the JBL 4722 speakers that I'm playing around with and would like to further explore horns.
how is it possible to be deep and not beam? which horns?
Does the me464 horn need a tweeter horn?
Does the K-402 horn need a tweeter horn?
which horn is better from 500- 4k?
how is it possible to be deep and not beam? which horns?
Does the me464 horn need a tweeter horn?
Does the K-402 horn need a tweeter horn?
which horn is better from 500- 4k?
Unfortunately we have moved off the topic of compression drivers and onto horns. They are certainly related, but the topic of horns should be in another thread - and there are plenty of horn threads. If you have a specific horn topic that doesn't already have a current thread, feel free to start one.
No, not if the compression driver is good to 16-20 kHz without chattering (i.e., non-pistonic motion).
More on that subject can be found here.
Chris
Pano, which compression drivers do you like on your multicells? Serious question here, no joking around.
I have to agree about what you've said about multicells. I have no idea why they sound as good as they do ... and it has nothing to do with "vintage" sound. You want vintage, try an AR-3 or EV Patrician. That's vintage.
I'm hoping my little adventure with the Yuichi A290 lands me halfway between the sonics of a multicell and the latest low-diffraction horns, although I don't expect the stupendous scale of the really big multicells. I still find it remarkable the "fingering", which looks so terrible on polar maps, is barely audible in a normally furnished living room. I strongly suspect audibility of polar map disturbances depends very much on the frequency band and the listening room itself.
Anyway, thoughts on compression drivers, for some of these old-school horns, are appreciated.
I have to agree about what you've said about multicells. I have no idea why they sound as good as they do ... and it has nothing to do with "vintage" sound. You want vintage, try an AR-3 or EV Patrician. That's vintage.
I'm hoping my little adventure with the Yuichi A290 lands me halfway between the sonics of a multicell and the latest low-diffraction horns, although I don't expect the stupendous scale of the really big multicells. I still find it remarkable the "fingering", which looks so terrible on polar maps, is barely audible in a normally furnished living room. I strongly suspect audibility of polar map disturbances depends very much on the frequency band and the listening room itself.
Anyway, thoughts on compression drivers, for some of these old-school horns, are appreciated.
"Normally furnished" implies that early reflections are not well controlled enough in-room to experience what I've found...
Here is my experience with better horns and compression drivers, minimizing crossover filter all-pass phase growth, controlled directivity down to 100 Hz (instead of ~800 Hz using direct radiating woofers), and controlling early reflections. On the same thread page, this is where I managed to reduce crossover all-pass phase growth dramatically, and using only IIR filters (not FIR).
After that point, I began to really listen to the music and forget about the hardware. Four years later, I'm still listening to the music and basically forgetting about the loudspeakers/electronics/room treatments. I found an apparent threshold that is reached where this subjective effect occurs, and it doesn't take anywhere near an anechoic chamber to achieve it (which, of course, would be a terrible place to listen, in my experience). Just attention to three details: full-range directivity, good inherent loudspeaker transfer functions in-room (smoothness and freedom from chatter) and avoiding all-pass phase growth due crossover filters, and avoiding strong early reflections.
Chris
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Typically the phase plug is a more pronounced source of limitations to the bandwidth of the driver, especially when placed in a horn. In order to perform at high frequencies in a horn the integrity of the wavefront is a key factor. At high frequencies we typically get a lot of rotating modes in the phase plug which leads to large changes in the wavefront shape. When the wavelengths are tiny, these changes are significant and the horn can not propagate these distorted wavefronts and reshape them as intended. This results in lack of high end energy, consistency and dispersion.
Yes, if you also pay attention to early reflections in-room from adjacent walls (using room boundaries below ~100 Hz to reduce bass modulation distortion), racks of equipment near the loudspeakers, coffee tables near the listening positions, and reflective headrests (leather or leather-like) chairs.
Chris
Chris
Right. Assuming straight-sided throat walls in the horn and 2" compression driver, anything above 6.9 kHz (13.8 kHz for 1" compression driver) is really controlled by the phase plug and/or its possible extension like the Klipsch patent application. This corresponds to a half wavelength of sound across the throat entrance.
Chris
Indeed, and the Klipsch patent is a sort of resignation saying "we have given up on solving this issue".
I works, however. Roy D. (Klipsch) mentioned that he had discussions with Mark Dodd (Celestion) over the driver (Axi2050) and horn (K-402). One can only assume that the extension is the result of those discussions.
Chris
Chris
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The "fingering" is caused when the horn is driven by a nearly flat wave front (which is usually the case for most compression drivers and adapters.) because the channels do not combine phase coherent at fin/channel exit. The fins should be compared to a phase plug where the designer intends to make the channels/paths of equal length or nearly equal. Although the fin distribution could be changed to mitigate the fingering.
That's a good enough explanation. However, I assume that there are probably more dynamics going on in those old multicell horns, since they were designed before the current tools (BEM, FEA, etc.) were available. Experience and elbow grease had to make up for as much as possible.
I think that's why we had dome diaphragm radiators for so long: lack of analysis tools. I think that Jack Oclee-Brown found fertile ground in applying late 20th century engineering tools to the problem of diaphragm and phase plug design. I assume that there will be other drivers that follow in that vein, but it was pretty amazing to see and hear that extremely large diaphragm and phase plug perform as smoothly as it does on the K-402.
Chris
I think that's why we had dome diaphragm radiators for so long: lack of analysis tools. I think that Jack Oclee-Brown found fertile ground in applying late 20th century engineering tools to the problem of diaphragm and phase plug design. I assume that there will be other drivers that follow in that vein, but it was pretty amazing to see and hear that extremely large diaphragm and phase plug perform as smoothly as it does on the K-402.
Chris
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Cask05,
just a bit off topic here but I think it's a bit sad you would only chose to develop your discussion around a moderator (if I understood correctly and that was not one of the rare jokes). 😉
I learned a lot in the past two days about why I prefer old school horns. Your dialectic with Pano was super informative. 🙂
On the business of 'beaming' I am still at a complete loss. My ears must be insensitive to happens between 16-20KHz while other factors seem to play a much more important role for me.
just a bit off topic here but I think it's a bit sad you would only chose to develop your discussion around a moderator (if I understood correctly and that was not one of the rare jokes). 😉
I learned a lot in the past two days about why I prefer old school horns. Your dialectic with Pano was super informative. 🙂
On the business of 'beaming' I am still at a complete loss. My ears must be insensitive to happens between 16-20KHz while other factors seem to play a much more important role for me.
The Axi2050 is a nice design but I see it more on the LF part. Have seen application in large horns below 100Hz. But the diaphragm is huge and I doubt that it performs on the same high level beyond 3k-5k. And the K402 has a throat design issue.
Actually, the beaming problem typically starts at 6.9 kHz for 2" compression drivers, ~9.7 kHz for 1.4" drivers, and 13.8 kHz for 1" compression drivers. If you find the patent application that I posted earlier for the phase plug extension, you will actually see the problem and a solution to that problem. Alas, it is under patent application and Klipsch isn't selling the extensions (and apparently has no intention of doing so without a pair of $35K USD loudspeakers attached to them), so legally, you're out of luck. If you choose to ignore that apparent roadblock, then...
The only way that you can really hear the difference between HF beaming and good HF polar coverage is to actually hear the two in your listening room. Or you could go to a live acoustic instrument concert (unamplified), particularly percussion instruments and perhaps violins/human voices, and you will hear a large difference in sound quality.
That's unfortunate that you've chosen to not hear a good setup with something like K-402s, etc. I think you would immediately change your mind.
First off--my name is Chris. I sign each message with it.
I'm actually sorry that it came down to what it did since I find it extremely distasteful to talk about such things on forums. If I thought that PMs would have addressed the issue, I clearly would have used them instead.
About 30 years ago, when I was inducted into a pretty widely known interdenominational religious study group (BSF) and was immediately asked to become a weekly in-person moderator of 16 guys (in addition to the separate weekly discussion leader meetings early on Friday mornings), I learned first hand why moderators cannot really share their own feelings with their members at the same time they are trying to moderate...it just doesn't work very well. I tried on separate occasions to do just that, and found that it creates problems for the members that they just didn't need. They are put into a no-win situation of trying to discuss the subject matter without appearing to disagree with their moderator. All the other moderators that I shared Friday morning meetings with all concurred (there were 15 other moderators plus a main discussion leader). They all said the same thing: it doesn't work. So when I finally accepted that, I found the discussions to be much more animated, insightful, and diverse. That was a big lesson for me. Apparently, that lesson is not widely known on internet forums. YMMV.
Chris
I think you need to add the expression, "in my opinion" to these two statements of belief. They are, in fact, not statements of truth, in my direct listening experience, which is reasonably extensive for these two items.
Chris