Is it possible to cover the whole spectrum, high SPL, low distortion with a 2-way?

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I would say, if constant directivity is not possible, then at least slowly and smoothly narrowing at the high end. I was really surprised by the great performance of the Keeley expo-conical radial horn in my EV SH1502ER speakers. According to the paper, a 290 Hz horn based on this principle would be quite huge, so I will most probably try to model one usable from 600 Hz up. Also, Wayne Parham's paper on his speakers recommends a CD horn with 90 x 45 dispersion and offers some useful info on his crossover design philosophy.

I believe that 15" (or even 12") + a large CD horn is the way to go, even if the crossover point is at around 600 - 1000 Hz. Of course, I mean two way with subwoofers. And I would be very tempted to horn load the woofer. High SPL, sensitivity and low distortion from ca 80 - 100 Hz up is not too difficult I'd say.

cowanaudio, thanks for the remark about using delay for correcting offset - I have not realized that, I always thought about on axis only.
 
There was no mockery, I'm sure Dr. Geddes is confident in his abilities and isn't offended in its presentation or by me, nor did I intend there to be, rather, I 'm prying for some better convincing.

Every time this has been brought up words like "constant directivity speakers... home listening conditions...universally preferred" are used...did you even notice that these speakers are not exactly for home listening conditions lol

Warrants a perfect array of stand points for a person who is ignorant (me) to what is supposedly going to result of the beaming.

How exactly is the highly directive spectrum, lacking room energy, going to sound, in the sweet spot and why?

I don't think that question has been answered by the constant directivity team. The "I'm ok with traditional long horns" team says that round long horns....in the sweet spot, are for "pure signal elitist".... and the only argument #TeamCD has really brought to the table is that "most people prefer CD" and "the perception will be different" lol. I'm not calling #teamCD a liar either. I am just asking to please provide more info!
 
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I have tried many a horn......beaming at high frequencies...nuts...moving my head ....inch or two ...mid/high frequency response significantly changed, both in measurements and listening. That's why I went CD and ....looked back.
Ok, so Mitchba has pretty much made the same comment earlier in the thread. When you say "an inch or two" am I supposed to take that as literal? You measured this inch? I took it as exaggeration, like someone saying "I've been waiting forever". Around the time Mitchba made the comment, Kevin (owns axi2050 and 250hz tractrix horns) says the beaming results in a sweet spot the size of a love seat or so, in a listening triangle spread out, 8x8x8ft.....those are two different experiences...makes no sense how exactly both experiences differ so much but Kevin gave more details so he wins....
 
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You know what, now that I think about it, I've heard (during my listening escapade, last spring) a somewhat clouted monitoring...(at least the store owner says it was) ...system, that used an AMT tweeter in the middle of two, inverted dust capped, 4" woofers....a popular setup I guess. Anyways, is that beamy enough? Its more beam than a 1" tweeter at least. In the sweet spot, it was fine, outside the sweet spot, the expected happened....is that a close enough experience?
 
I assume Cow is referring to me. I've never been called that before. Novel.

The room sounds dark. It is quite obvious. This was in a room that was quite a bit larger than a domestic space too. The system sounded bright and the room sounded dark, it just didn't work, for me at least. The owner of that system exclusively does CD now. If you've been following along you have already seen pictures of the beamy system and the CD ones that followed it.
 
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I experienced something similar but it didn't seemed to me the room was dark ( the room wasn't this large), but there was some mismatch between the loudspeaker and the room.
I thought it was because the ratio of ER/difuse field was changed and the fact the room was kinda polarized with most reflection coming from the back which might play a role too.
 
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Pano:Behind listening position, facing the loudspeakers.

Room polarisation i used to describe some control rooms acoustics where you have for example the front of room ( where loudspeakers are located) being fully reflective and the back fully covered with diffusors.
Live End Dead End are an example from the one i've seen.
There was the same kind of effect to me.

Camplo have you ever heard an RFZ?
 
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OK, thanks. I don't like too much reflection from behind me, so I understand. :up:

Well specular reflection i don't. If decorelated and spread they can give the feeling the room doesn't have backwall and being larger it actually is.
That said i've had the feeling in some control room their was a price to be paid, the character of the difuse field is somwhat synthetic sounding to me, not very natural. It reminds of some algorythmic generated reverb effect.

Probably a pattern within the difusor at work.