You don't need to travel or be an able DIYer to listen to the horns and drivers you own.
Your hunch, choice or guess in what you purchased was good.
It appears your continued "second guessing" of horns that are not available for you to hear in your own listening environment is crippling your potential enjoyment of what you own.
It's response does not look particularly bad regarding fingering.
That exponential bi-radial horn has a narrowing of it's directivity as frequency rises (beaming) and it's frequency response is not as smooth as yours.
It's rising raw on-axis response indicates it is more "beamy" than yours.
The low end ripple ("subtle resonance at 400Hz"?) goes along with it's reduced vertical mouth dimension compared to yours.
It's 2" throat has more top-octave response anomalies than yours.
In general, the vertical response of any horn with a vertical height less than it's width will exhibit pattern flip, the vertical dispersion becoming wider than the horizontal at the low end of the response.
Taking the time/$$ to produce charts and publishing those types of "features" don't drive sales of these boutique items which are usually purchased more for their appearance than technical details.
The asymmetrical vertical response of Crowe's horn #1670 with the tweeter horn #1671 would certainly not "look good", regardless of whether you think it's new ten degree draft angle providing a "more aggressive appearance" "looks cool".
Art
No, because among other things, Troy has my sealed Altec midwoofers, so it's how could it not be other than ludicrous to drill out brand new 425 horns and use brand new Radian 745Be drivers and expect what audio I'd manage to produce to be at all discernible to my ears/brain as good sound. Maybe you, Camplo, Docali and Troy could work that kind of magic and from the audible results know what to do next, but not I.
Please excuse the word count.........
Years ago, hunch #1, and clearly my best hunch, was to purchase the Altec 416-8Bs, largely based on Lynn Olson's and later Gary Dahl's glowing description of their sound. But when I later learned that the 416s are too sensitive to work with nearly all direct radiator midrange drivers, I got the 425 horns and Radian 745Bes to clone Gary Dahl's speakers. Indeed, Gary was thrilled with their sound for well over a year. But after a while it became clear to him that the Radian Bes produced a “hardness” that no voicing scheme he devised could eliminate. Luckily for Gary, his hunch on swapping out the Radians for the Yamaha JA6681B proved the perfect solution, as he had no issues with their 10kHz limit. See post 26.
https://www.diyaudio.com/community/threads/compression-driver-impedance-question.318749/page-2
Gary’s a highly capable DIYer; his builds and extensive upgrades on Lynn’s and Gary Pimm’s amps are awesome. But it obviously took Pierre’s EE chops to perfect the contour circuit and voicing for the Radians in the 425s to make a winning two-way system. See 15266, 15276. https://www.diyaudio.com/community/threads/beyond-the-ariel.100392/page-764
Looked like I was on my way out of the rut? But not necessarily for a few reasons. As great as the 425s had sounded to Pierre, he preferred the wide and deep sound stage that he found from the TH4001 horns, which produces the “You are There” sound that I too was looking for.
But though poised to jump on Pierre’s RadianBe HF extension filter, order the Athos version of the TH4001 horns and purchase a pair of Pierre’s throat adapters which were based on Docali’s design, Marco had convinced me to avoid using any adapters.
Instead, Marco and Docali suggested if using a 2” horn like the TH4001, the biradial that Marco https://exclusive-audio.jp/en/produ...Mq_EAYxI2ZOxlzJmxiinIrxFAd53PtbFfM_NIA0NsarO6 or Docali https://alg-audiodesign.com/pavillons/ had suggested, that I should use a 2” driver https://usspeaker.com/jbl 2450H-1.htm , not the 1.4” Radian.
But the Yamamoto SS300 are $9.5K/pair, plus shipping and duty and Trump tariff taxes. ALG provided no measurements on their horns. And while plots of NicoB’s X-shape and/or Next Gen TH4001 look impressive https://audiohorn.net/x-shape-horn/ https://audiohorn.net/next-gen-bi-radial-horn/ , I’ve yet to find any users of either horn for gathering feedback; also, NicoB and Docali had earlier seemed to have locked heads a lot on
several issues here on this thread.
Therefore, since Troy Crowe has my Altec midwoofers going with his ES450s or ES290s seemed like the best bet. With the ES290, coverage starts at 120 degrees and narrows to 90 degrees at 8kHz with a three-way system, or 60 degrees with a two-way. Would not this relatively low directivity index horn yield a very convincing “You are there” sound? https://josephcrowe.com/blogs/news/bms-4591-with-horn-no-1670
Nor is a throat adapter needed with the ES290. https://josephcrowe.com/products/es-290-biradial-wood-horn
The question then is what would the off-axis response be with the 1.4” Radian Bes? IF it was very good Troy would need only have to add and fine tune Pierre’s or his own HF contouring filter for the Radians to do a two-way system.
And from post 185, https://www.diyaudio.com/community/...001-clones-makers.375215/page-10#post-7798542 , assuming Art’s comparisons of the Altec 416 to the EV15 is accurate, then even if the Radian must be crossed at 900Hz https://www.usspeaker.com/radian 745neoBepb-1.htm , the Altec won’t get noticeably beamy.
But even so, would not most 2” drivers themselves, and perhaps also then allow the midwoofers, to deliver more male vocal authority? This was definitely what both Troy and Bappe found to be exceedingly true of the B&C DCM50. Scroll down end here for Troy’s listening tests. https://josephcrowe.com/blogs/news/es-450-biradial-no-2143
The DCM50 combined with the Fostex 925A tweeter would surely deliver awesome listening pleasure, and I am very torn about not going with it! But the DCM50’s warm sound, while likely not at all fatiguing, might thereby lack the neutrality and detail of drivers like the Yamaha JA6681B or berylliums, as Pierre had cautioned. Likewise, quoting Anders:
The DCM-50 is a very nice midrange driver that I used for some time in my e-jmlc300 and my intention was to top it off with the T900. The issue I faced was that I did not like the DCM over say 4k. The best result I had was to top it off with a 1" Celestion on a e-jmlc1000, crossing over at 3k. In the end I decided to go for the JBL 2451 with Be diaphragms in order to get a more coherent top end. This shift forced me to lift the crossover point a bit but all-in-all, a major lift in subjective performance to my ears.
I found the TAD's TD4001 lacked impact in the lower end and sounded a bit forward in the upper midrange, the midrange part could be EQ'd but that sort of robbed it of its "magic". In went the DCM50. That pretty much fixed the low-end problem but matching it to the T900 was impossible to my ears. Maybe I had gotten too used to the very crisp and impactful lower treble of the TAD? I did end up crossing them around 4k to get a balance that i could live with. I had a pair of JBL 2451 laying around so after a while I took the plunge and ordered some Radian Be diaphragms just to try them out and bingo, there it was. I lost the awesome authority in the low end that the DCM had but the rest was better than both the TAD and the DCM! Subjectively it is more consistent over the whole spectrum than the TAD at all listening levels and to my ears an almost electrostatic like lack of distortion but with great impact and dynamics. To gain back some of the midrange weight and impact the DCM had, my plan is to add a short front horn to the GPA woofers and play with the crossover a bit.
Furthermore, can’t most 2” drivers cross at 500Hz (with the proper horn), much lower than the Radian 745, thereby allowing let the Altec midwoofers to play at their lower upper range, and thus maximize their lowest directivity index (for “you are there” presentation), while producing their least distortion and highest output at ~100Hz, above my subwoofers?
That’s why I asked about alternatives to a $$$$ 2” JBL2450J (16ohm) + beryllium diaphragms for use with the ES290, though I might bite that bullet if the horns end up being not to crazy expensive, and hopefully later find a buyer for the brand new RadianBes.
BUT Troy’s had my midwoofers for well over a year and wants to complete this project, so I need to decide on a driver very soon.
Trust me, IF I knew for a fact that my ~ 3000 cu ft room could take two pairs of speakers, plus my three subs, I’d look to build with the 425 horns first. But with the above realities and stated goals……
1/) Directivity for producing “You are There” soundscape.
2/) Horn/Driver combination for avoiding need for throat adapters.
3/) Horns with wide and deep sound stage, so long as reflections can be tamed without any extensive structural room mods.
https://acousticfrontiers.com/
4/) Driver (s) with lower midrange authority, zero fatigue, neutrality, effortless detail, airy highs.
5/) Selecting midrange driver to maximize all performance aspects of Altec midwoofers.
6/) Horn/driver solution agreeable to my builder Troy Crowe so that Altec midwoofers can then be directly shipped to me as part of a completed, measured and proven build.
Thus, either the ES290 or another (from the links above?) 2” biradial look to be the way to go.
If I’m somehow wrong on the points, please explain.
But as explained I do have to wrap this up with Troy ASAP.
Your horns and drivers are now considered "used", drilling mounting holes won't change their resale value.
You don't need woofers to listen to horns, but you do need to mount the drivers.
If your ears/brain can't discern good sound, all the discussion about what to choose next is a waste of time.
Your hesitance to use what you own is based on hearsay from others listening in different environments, with different hearing, and experience levels.
You can't know if your ultimate preferences will align with their different, and ever changing perceptions.
Nothing wrong with that, any more than choosing a car, a piece of art, or a video monitor based on others opinions without having experienced them yourself.
As far as points (goals?) 1-4, your 425 horns/Radian 745Be with proper crossover design will certainly work well for all of them, and I could (but won't) argue even better than the alternate choices you are considering.
As to point 5, your 425 horns/Radian 745Be should cover the entire range above the Altec 416-8Bs quite well and eliminate a problematic mid horn to tweeter horn crossover region.
As to point 6, can't say what would or wouldn't be agreeable to your choice of builder.
Art
Pierre:
"In the mean time, I just wanted to share that the JMLC and these sectoral horns don’t sound coloured, and are fun to own and compare, just like fine wine."
Add sailboats, motorcycles and hang gliders to the list too.
I've eliminated the last three choices to simplify and extend the time available to appreciate other comparisons😉.
"In the mean time, I just wanted to share that the JMLC and these sectoral horns don’t sound coloured, and are fun to own and compare, just like fine wine."
Like cars, art, and video monitors, wine is another one of those things best chosen by personal taste.
Add sailboats, motorcycles and hang gliders to the list too.
I've eliminated the last three choices to simplify and extend the time available to appreciate other comparisons😉.
Yes, as shown in this Geddes plot Troy's ES290 horn does narrow with increasing frequency
https://cdn.shopify.com/s/files/1/0...BMS_4591-8_off-axis3_480x480.png?v=1649504045
He admits this here.
https://josephcrowe.com/blogs/news/es-450-biradial-no-2143
All exponential horns have a gradual narrowing of the directivity as frequency rises, and this horn is no exception.
But adds: What is important here is that the response is consistently even as you move off axis. Any disturbances will be an indication of edge diffraction which is a source of resonances, which give horns a coloured sound. There is a minor irregularity at 4kHz, otherwise this is a textbook polar map.
https://cdn.shopify.com/s/files/1/0..._BMS_4591-8_off-axis_480x480.png?v=1649503931
How true is this of the 425 horn? I have yet to find a directivity plot of that horn to compare to the ES290, but as Lynn Olson said it has a ~4 ft sweetspot, it's seems reasonable to conclude that its directivity would be far more narrow than the ES290's. Consequently, would not the ES290 do far better at delivering a "You Are There" (rather than "They are Here" ) presentation?
I think we may have been through this before. There are issues with this statement.
By the way, an axisymmetric LeCleach horn is an example of an optimum exponential horn because it respects waveguide theory as well as horn theory.
They are Here (your Room) You hear strong indication of the reverb character of your room (Low DI) (Livelier Room)
You are there (the Acoustical space of the Recording) the reverb character of the recording(via Direct sound), is the leader in perception of acoustical space (High DI) (More Damped acoustical space)
Earl Geddes found Bjørn Kolbrek's BEM simulations to be accurate (for the most part) for his OS horns.
From Bjørn Kolbrek's BEM polar simulations of the AH425 and actual on-axis measurements, the AH appears to have a smoother, more consistent narrowing response with less edge diffraction than the ES 290 or 450 bi-radial.
The 450 bi-radial can not be as smooth or have less diffraction in the vertical plane due to it's asymmetrical design.
Not a reasonable conclusion, the "sweet spot" would be 2 foot at half Lynn's listening distance, 8 foot at twice the distance.
In the horizontal plane, the ES 290 or 450 bi-radial have about a 5 degree wider dispersion at 10kHz than the AH425, ~10% more narrow.
To echo AllenB, we have been through all this before.
Several times..
Camplo and I have pointed out the "You Are There/They are Here" dichotomy regarding a horn that changes it's DI with frequency several times before.
You won't "get it" until you listen to your horns, though that won't happen until you stop going in and out this endless Deja Vu rabbit hole🤢
Art
Be that as it may, I was talking about a discussion of the quote from the other site.
First, I finally found some worthwhile data on the 425 horns.
https://horns-diy.pl/horns/jmlc/jmlc-400/# Click on that plot. Despite its other ascribed virtues, as it's anything but a CD horn, even the on-axis curve shows that its response drops rapidly above 5kHz. Or is this before some kind of "contouring" filter is applied to extend its response?
Second, I truly don't mean to sound ungrateful, but I cannot and will not attempt to DIY assemble and test this 425/Radian combo myself. Either one of you will simply have to fly out here to Long Island and help do it (just kidding), or I'm going to have to find someone at this or another forum with 425 horns in their system-and within ~ 300 miles of Long Island-who will invite me to hear them.
Therefore, as none of this will happen anytime soon-AND as my builder Troy Crowe has now given me until April to decide on a horn or else, please let us move on to other horn suggestions for above my midwoofers. https://josephcrowe.com/blogs/news/altec-416-8b-in-100l-sealed?_pos=8&_sid=085086a60&_ss=r
NicoB's horns.
https://audiohorn.net/x-shape-horn/
https://audiohorn.net/next-gen-bi-radial-horn/
Docali once suggested https://alg-audiodesign.com/ but he didn't specify which horn (s).
Some other (SEOS?) horn ideas?
https://www.audiosciencereview.com/forum/index.php?threads/compression-drivers.29697/page-10
Driver: SB Audience 65 CDNT gets lots of praise for use in a two way system.
And Troy offers this.
https://josephcrowe.com/products/3d...-audience-65cdn-t?_pos=1&_psq=sb&_ss=e&_v=1.0
And Troy offers this.
https://josephcrowe.com/products/3d...-audience-65cdn-t?_pos=1&_psq=sb&_ss=e&_v=1.0
The Auto-Tech JMLC-400 is a different size than the AH425, made by a different company.
The measurements list the driver as a 2" D1500-Ti, a driver of unknown origin.
The measurements of the JMLC-350 also listing the above driver are not consistent with the JMLC-400/D1500 response.
No test protocols are mentioned, so I won't try to guess why their tests are not internally consistent, or why they chose a driver which appears to have erratic response above 4kHz.
If you and your builder don't want to use your AH425/Radian combo, my suggestion would be to use whatever he suggests.
Cheers,
Art
Please check out my last three posts here.
https://www.diyaudio.com/community/...orns-you-can-actually-buy.329476/post-7939523
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I have checked out your last two (repeat) posts in this and the "large constant directivity horns you can actually buy" thread.
Can't help you choose your compromises any more than I have already.
I'd now suggest you buy a Magic 8 Ball to answer your questions.
Can't help you choose your compromises any more than I have already.
I'd now suggest you buy a Magic 8 Ball to answer your questions.
FWIW, if you happen to like the presentation of JMLC horns, this Reddit poster raves about the soundstage of this build with the Radian 950s. Beryllium version, though.
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They were quite good with a JBL horn I used to have, but performed poorly with the A-290 as noted in previous posts. I finally managed to find a new home for the Radians a few days ago.
Sorry, but I'm still somewhat confused. Are you saying that it's the AH425 which will most present "You are There"?
Not this https://alg-audiodesign.com/pavillon-iwata-2/
or these https://audiohorn.net/x-shape-horn/
https://audiohorn.net/next-gen-bi-radial-horn/
https://josephcrowe.com/products/es-290-biradial-wood-horn
I'm trying to relate this to what Weltersys said here.
https://www.diyaudio.com/community/...orns-you-can-actually-buy.329476/post-7962512
Oh my!
My suggestion (FWIW, and last time I'm posting in this thread):
Go with Troy's ES290 horns. You've already made the choice to select him as your builder, and he has your woofers and cabinets. He makes those horns himself (so he will not object to them), they're good products, and they can be made to match with a number of compression drivers (Troy understands the importance of throat angle matching, so he won't recommend a poor match).
My own personal recommendation for a compression driver would still be the JBL 2450 plus Be diaphragms, or failing that, with JBL non-ribbed, Aquaplas-coated Ti diaphragms (as originally used in JBL's K2 S9500 loudspeakers).
You won't need a separate tweeter in either case.
(If you later decide that you still want one, you can always add it... but that opens up another can of worms. E.g., accept that it is impossible to time align a tweeter at such high frequencies and you will get comb filtering... but then again that's arguably not such a big deal... so it's all a matter of trade-offs)
Lastly, for heaven's sake, forget all about the "You are there" thing. This is becoming an obsession, and frankly you still don't seem to really get what it means, nor what it implies/requires.
Bottom line is, ALL horns will give you more of it than ANY direct radiators, so don't worry, I'd bet you'll be ok in that regard.
Now, go ahead and seal that deal!
Then sit back, relax, and (FINALLY) get off this forum and enjoy some music with your new speakers. They'll be awesome, I'm sure.
My suggestion (FWIW, and last time I'm posting in this thread):
Go with Troy's ES290 horns. You've already made the choice to select him as your builder, and he has your woofers and cabinets. He makes those horns himself (so he will not object to them), they're good products, and they can be made to match with a number of compression drivers (Troy understands the importance of throat angle matching, so he won't recommend a poor match).
My own personal recommendation for a compression driver would still be the JBL 2450 plus Be diaphragms, or failing that, with JBL non-ribbed, Aquaplas-coated Ti diaphragms (as originally used in JBL's K2 S9500 loudspeakers).
You won't need a separate tweeter in either case.
(If you later decide that you still want one, you can always add it... but that opens up another can of worms. E.g., accept that it is impossible to time align a tweeter at such high frequencies and you will get comb filtering... but then again that's arguably not such a big deal... so it's all a matter of trade-offs)
Lastly, for heaven's sake, forget all about the "You are there" thing. This is becoming an obsession, and frankly you still don't seem to really get what it means, nor what it implies/requires.
Bottom line is, ALL horns will give you more of it than ANY direct radiators, so don't worry, I'd bet you'll be ok in that regard.
Now, go ahead and seal that deal!
Then sit back, relax, and (FINALLY) get off this forum and enjoy some music with your new speakers. They'll be awesome, I'm sure.