This type of mountainrange fq-response is typically a big turn-off for diy builders, especially for non DSP folks. Even a ‘normal’ plate amp like a Hypex with its limited PEQ:s won’t really make this palatable. The “flying squirrel” filter needed for a smooth handover from cone to cd, the drooping response of the 18”, the break up close to the passband of the cone drive, all are sort of the opposite of f.i. a Purify/Dome driver setup.
Attachments
Mabats ATH4 and Augerpro's waveguide simulations have reached advanced levels. It might be an idea to focus on optimization of diy mini-waveguide+compact tweeter combo's that would be suitable to be built into existing (mid-)woofers. Member 5th Element did that with B&W mids.
Many years ago I did some crude attemps, but without optimizing the first section (a la KEF) , results around 8-10 kHz are far from optimal. Then the cone termination is next....
Many years ago I did some crude attemps, but without optimizing the first section (a la KEF) , results around 8-10 kHz are far from optimal. Then the cone termination is next....
Some people mention horn speakers, but what, if any, advantages does a horn offer compared with other speakers? Yes, the shape of a horn is such that a horn has a continuum of standing wave frequencies.
not just a Kevlar B&W, a paper cone 5” Satori, and a 6” metal cone SB Acoustics driver. He’s cracked the code for sure. @5th element
Good times ahead without needing a large MEH. (not that there’s anything wrong with that)
Watch this space!
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It is much like tube amps and folks that like vintage drivers.
Which often comes to mind when coaxial is mentioned.
Sometimes there is a romance with them. Aesthetically
and historical value.
Otherwise many modern drivers are more live sound
so the high efficiency is attractive. maybe more challenging
crossover.
Far as mounting another driver in front of another.
I see the space saving property the advantage.
Or just something fun to do.
Have thought of using a sealed back driver for the application.
which would allow foam or felt to be mounted to the back
to reduce diffraction.
Having seen " beam blockers" for pro audio.
Mounting another driver seems to be a fancy
beam blocker. So depending on the application
and crossover points. I seen the front mounted
driver a issue, and then not really a issue.
Depending on what you actually hear, or what people
" think" they hear
Deemed not common in some aspects.
but incredible common in car audio.
Being car door is a horrible baffle.
And listening position horrible.
Having heard rather glorious audio
in cars.
Tend not to overthink, and with DIY
you can build what you want
Which often comes to mind when coaxial is mentioned.
Sometimes there is a romance with them. Aesthetically
and historical value.
Otherwise many modern drivers are more live sound
so the high efficiency is attractive. maybe more challenging
crossover.
Far as mounting another driver in front of another.
I see the space saving property the advantage.
Or just something fun to do.
Have thought of using a sealed back driver for the application.
which would allow foam or felt to be mounted to the back
to reduce diffraction.
Having seen " beam blockers" for pro audio.
Mounting another driver seems to be a fancy
beam blocker. So depending on the application
and crossover points. I seen the front mounted
driver a issue, and then not really a issue.
Depending on what you actually hear, or what people
" think" they hear
Deemed not common in some aspects.
but incredible common in car audio.
Being car door is a horrible baffle.
And listening position horrible.
Having heard rather glorious audio
in cars.
Tend not to overthink, and with DIY
you can build what you want
Yeah spendy. But the compression drivers alone are $$$. The P.Audo 18” coax was a relative bargain when they were made at $750 a pair. That would be $1000 today.
@WhiteDragon Yes, you've hit the nail on the head. It's visually impressive and makes you want one - and the 16" cone does work well with the 1.4" compression driver.
But I don't want to drag this off topic, I'll be posting more about my project in late May or June.
But I don't want to drag this off topic, I'll be posting more about my project in late May or June.
In a manner of speaking, modern waveguide design is about understanding and moderating non-essential modes.
Yep just do it yourself!
Attachments
I number of people asked me about the applicable patents and info about the KEF coaxial design:
Stiffening ribs to push up first breakup frequency:
https://patentimages.storage.googleapis.com/c0/cb/5e/d0dc2981970841/US8942407.pdf
This describes the phase plug on the tweeter:
https://www.researchgate.net/profil...hase-Plug-and-Novel-Rigid-Body-Diaphragms.pdf
Surrounds:
https://patentimages.storage.googleapis.com/d5/95/30/9f2dcabbd76047/US9271082.pdf
you can probably find more with searches for Jack Oclee-Brown and Mark Dodd, : GPACOUSTICS (UK) LIMITED,
Stiffening ribs to push up first breakup frequency:
https://patentimages.storage.googleapis.com/c0/cb/5e/d0dc2981970841/US8942407.pdf
This describes the phase plug on the tweeter:
https://www.researchgate.net/profil...hase-Plug-and-Novel-Rigid-Body-Diaphragms.pdf
Surrounds:
https://patentimages.storage.googleapis.com/d5/95/30/9f2dcabbd76047/US9271082.pdf
you can probably find more with searches for Jack Oclee-Brown and Mark Dodd, : GPACOUSTICS (UK) LIMITED,
And the multiple whitepapers from the 2 lasts range of Kef's products ( the one availlable at Kef's product pages and with a bit of googling for the older one).
Kipman725 you work(ed in relation) with them?
Kipman725 you work(ed in relation) with them?
@5th element very cool. I think I recognize that tweeter. Is it back mounted to the magnet pole of the woofer?
here's some coaxial's
Seas 112re/xfc
Trenner & Friedl
https://www.stereophile.com/content/trenner-friedl-sun-loudspeaker
https://www.madisoundspeakerstore.com/coaxial/seas-prestige-l12re/xfc-h1602-5-alum/fabric-coaxial/
http://www.seas.no/images/stories/prestige/pdfdatasheet/L12RE_XFC_AppNote.pdf
Dayton CX120-8 from PE Forum
https://techtalk.parts-express.com/forum/tech-talk-forum/1426474-cx120-8-easy-build
Dayton CX150-8 from PE Forum
https://techtalk.parts-express.com/...73-dayton-cx150-8-coaxial-project?q=crossover
$$$$$
https://www.dhtrob.com/impressies/phyhp_km30_en.php
Ceiling Speakers (gasp)- Focal IC108
https://www.focal.com/sites/www.focal.fr/files/shared/catalog/document/FT-IC108-gb.pdf
post#35
Polk MC60 (they don't look like coax)
- I have a pair in OB. I like them
https://6moons.com/audioreviews/polkingfun/1.html
Car Audio Speakers?
Seas 112re/xfc
Trenner & Friedl
https://www.stereophile.com/content/trenner-friedl-sun-loudspeaker
https://www.madisoundspeakerstore.com/coaxial/seas-prestige-l12re/xfc-h1602-5-alum/fabric-coaxial/
http://www.seas.no/images/stories/prestige/pdfdatasheet/L12RE_XFC_AppNote.pdf
Dayton CX120-8 from PE Forum
https://techtalk.parts-express.com/forum/tech-talk-forum/1426474-cx120-8-easy-build
Dayton CX150-8 from PE Forum
https://techtalk.parts-express.com/...73-dayton-cx150-8-coaxial-project?q=crossover
$$$$$
https://www.dhtrob.com/impressies/phyhp_km30_en.php
Ceiling Speakers (gasp)- Focal IC108
https://www.focal.com/sites/www.focal.fr/files/shared/catalog/document/FT-IC108-gb.pdf
Polk MC60 (they don't look like coax)
- I have a pair in OB. I like them
https://6moons.com/audioreviews/polkingfun/1.html
Car Audio Speakers?
John Wyckoff (RIP), Hammer Dynamics (sort of coax?)
http://web.archive.org/web/20020811011234/http://www.hammerdynamics.com/
http://web.archive.org/web/20020805004410/http://melhuish.org/audio/super12.htm#driver
http://web.archive.org/web/20020805...music.com/magazine/equipment/0600/super12.htm
from old Single Driver Website - James Melhuish
http://web.archive.org/web/20020603071230/http://melhuish.org/audio/index.htm
http://web.archive.org/web/20020811011234/http://www.hammerdynamics.com/
http://web.archive.org/web/20020805004410/http://melhuish.org/audio/super12.htm#driver
http://web.archive.org/web/20020805...music.com/magazine/equipment/0600/super12.htm
from old Single Driver Website - James Melhuish
http://web.archive.org/web/20020603071230/http://melhuish.org/audio/index.htm
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I've used the Dayton Audio CX120-8 and the Omnes Audio CX 3.1. Both have dome tweeters rather than compression drivers like pro coaxials often use. Both have some response irregularities, which are unavoidable when mounting a tweeter in the middle of a non-ideal cone shape, but they aren't too bad, and both sound pretty good to me.
newp I'm just an electronic engineer with an interest. It would be fun for my job to be designing such things!
on the subject of coaxs I have used the 12FCX76 in stage wedges:
thats with a passive crossover 2.83V.