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Why are coaxials so rare?

thewas

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1) At 1kHz wavelength is 34cm. Why would a 4cm bridge (1/9 octave) have a major effect on the emitted signal?
At 2,5 kHz we are already at 13,7cm.

2) Show me a standard layout speaker that has better directivity.
Better directivity than the 0°, 45° curves of the ME 100 you posted?

Here for example of the Dynaudio LYD 5, also a 5"/1" combo without waveguide where I plotted the 0° and 50° (as there are no 45° ones) from ASR:

1635163338667.png


A bit worse till 3 Khz but better above, but as said just 2 horizontal angles don't tell the whole story. Loudspeakers with will designed waveguides like Genelec, Neumann and Revel beat those of course easily.
 
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sarumbear

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A bit worse till 3 Khz but better above...
A bit worse is 3dB and 3kHz is where most vocal range ends.

Anyway; I simply asked why a design where the tweeter is on a bridge is used. So far all I heard is it shouldn't work but no explanation given that makes sense to an acoustician like me. When I showed an example of speakers out there that shows it to be working I was told that no manufacturer should be trusted. Those charts are phoney.

I give up. Forget that I asked the question.
 

voodooless

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A bit worse is 3dB and 3kHz is where most vocal range ends.

Anyway; I simply asked why a design where the tweeter is on a bridge is used. So far all I heard is it shouldn't work but no explanation given that makes sense to an acoustician like me. When I showed an example of speakers out there that shows it to be working I was told that no manufacturer should be trusted. Those charts are phoney.
I think you missed the nuance here. The question was: why does nobody do it? Answer that I gave: because it's hard! I never said it should not work.

And no, I do not trust manufacturers. We've seen too many examples of bad data, even from so-called reputable companies. Also, nobody called the charts phoney. They were called lacking in detail, which is absolutely correct. They are low resolution, and only two angles were measured. We have no waterfall plot to check for resonances and other decay products, nor do we have an idea of what the individual driver units do and how they interact. For a company that allegedly has such a fantastic anechoic chamber, the fact that you get only this kind of graph is quite frankly appalling.
 

voodooless

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Stumbled across a Charles Rodrigues chestnut today and I just felt moved to drop it into this thread, where (I would opine) it fits rather well actually.

View attachment 161380

(YMMV, of course)
;)
Oh, quite a few years ago I’ve seen a Dutch company slap a cheap ordinary 6x8 car audio coax on a few wooden boards and call it a high end audio product, complete with all the high end woo, and not only the audio kind :facepalm: At first I thought it was a parody, but it turned out they were for real.
 

mhardy6647

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I've found a few "Frankenspeakers" over the years that had been... shall we say... reanimated with automotive loudspeakers of various kinds. :rolleyes:
 
OP
Pearljam5000

Pearljam5000

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So which is the ultimate coaxial speaker
KEF, Genelec or Geithain or something else? :cool:
 

TimVG

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1) At 1kHz wavelength is 34cm. Why would a 4cm bridge (1/9 octave) have a major effect on the emitted signal?

I remember the KEF R3 test from Erin's audio corner where there were quite measurable differences at ~1,2kHz when the shadow flare (trim ring) wasn't sitting absolutely perfect down to half a mm.

1635191922168.png
1635191947794.png
 

sarumbear

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Timcognito

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Matias

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Thiel made quite a number product lines measuring very well. Example:
As a proud owner of a 3.7 I can say that this graph is very telling, they really are very, very wide up to the mid highs 6kHz and start directing from there.

1208T37fig7.jpg


More here:
 

sarumbear

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A much better implementation than the Geithaine
Why? We have not yet seen Geithaine speakers tested. How can you know, by looking at them?
 

JWAmerica

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Why? We have not yet seen Geithaine speakers tested. How can you know, by looking at them?
It's like seeing a poorly designed speaker with obvious comb filtering issues. But you're obviously emotionally invested in Geithaine speakers and no longer objective on the topic.
 

KSTR

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@JWAmerica , you really have no idea and you're just sharing your arm-chair musings.
MEG Geithain speakers are world-class and have stood the test of time in studios all around the world for decades. The RL900 has been around since 1984. And mind you, this a company from the former GDR and those guys are truly representing what is known world-wide as the proverbial thorough (East) German engineering paired with ingenuity, having to cope with lack of resources (well, at least they had time and were not subject to capitalist distractions).
Geithains measure well and sound fantastic. One of the few speakers in the world you can listen to for many hours without fatigue. Genelecs and many others make your ears bleed instantly, in comparison.
 

thewas

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Geithains measure well and sound fantastic. One of the few speakers in the world you can listen to for many hours without fatigue. Genelecs and many others make your ears bleed instantly, in comparison.
For listening of such "ear bleeding" recordings I would recommend then Geithain for people who don't or can't use EQ, a good friend of mine (music listener) has replaced his Neumann KH 420 with Geithain 921K and enjoys them more, mainly due to their cardioid bass though.

But on the other hand I would rather have music mixed and mastered on some as linear as possible measuring monitors like the Genelecs Ones if we want to get finally rid of audio's circle of confusion one day, otherwise we will still have recordings that sound only good with euphonically deviating loudspeakers like Geithain, B&W etc.
 

Sancus

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The biggest downside of Geithain is that they're not a realistic purchase outside of a small handful of EU countries. Unless you fancy an extremely expensive import that you can't see or hear beforehand, with no local dealer support and shipping back to Germany at your expense in case of any issues. Assuming they even honor their warranties outside of the EU.

For such good speakers you'd think they would try selling them in more places, lol.
 
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