With protruding/convex domes and nearby/close-up tweeters you will get a reflection from the dome midrange ... a suitable sculpted foam absorber could probably fix the reflection ... maybe this reflection is part of the reason why some expensive studio dome midranges have a short horn loading integrated so the reflection is only minor!
In case of doubt , compare responses of the tweeter with or without the neighbouring midrange dome (covering the mountig hole of the mid with some stable piece of cardboard) ... btw , in a MTM layout - the reflection is more pronounced!
In case of doubt , compare responses of the tweeter with or without the neighbouring midrange dome (covering the mountig hole of the mid with some stable piece of cardboard) ... btw , in a MTM layout - the reflection is more pronounced!
@Marveloudio TRUE! And most designer seem to don't care. With my MTM layout for my last project I decided to print new frontplates for the Bliesma midranges to reduce this effect. The short horns etc are also introducing an unsteday front baffle and I also got influences with it. I belive it's more about protecting the domes.
Are there ANY useful measurement sof this driver? FR from the manufacturer loks good but impedance ... not even this smoothing can even it out
https://www.swanspeakers.com/product/view?id=168
Looks like they would give a very compact package when the frontplate is removed.
The latge domes from ATC and Volt need to be recessed due to large magnets. They also do this to get the flange smaller to decrease driver spacing. I've seen custom versions of the ATC and Volt domes with partially machined flanges.
Its always beneficial to recess the domes for exactly the reason you stated, which however isn't that significant of a problem, even at higher SPLs. Morel recesses their domes as well as Dynaudio.
I designed a 3 way with D76 and D330 esotar drivers on which the reflection of the tweeter output from the mid dome was repeatably measurable. It didn't however cause any audible issues being so close in time with the rest of the direct audio coming off the baffle. Im sure you'll see a minor disturbance in FR from it but its so small that you couldn't specifically say it causes some sort of acoustic signature.
Its always beneficial to recess the domes for exactly the reason you stated, which however isn't that significant of a problem, even at higher SPLs. Morel recesses their domes as well as Dynaudio.
I designed a 3 way with D76 and D330 esotar drivers on which the reflection of the tweeter output from the mid dome was repeatably measurable. It didn't however cause any audible issues being so close in time with the rest of the direct audio coming off the baffle. Im sure you'll see a minor disturbance in FR from it but its so small that you couldn't specifically say it causes some sort of acoustic signature.
The height of the rubber surround is the problem please check with a thin but stiff disc having the appropriate diameter , lay speaker on the back so the disc touches the rubber surround and making any residuing gaps more air tight .
For me it is the main reason that SBA has recessed rubber surrounds integrated into their baskets like no(?) other manufacturer ..... for drivers without a dustcap but accessible center plug ("phase plug") one can cut a conical piece of acoustic foam (BASF/basotect in white or gray) to fill up the empty space , for absorbing any unwanted sound being reflected towards the microphone!
Now , where are the flat cone/disc drivers built by some heavenly creatures dancing in the moonlight
For me it is the main reason that SBA has recessed rubber surrounds integrated into their baskets like no(?) other manufacturer ..... for drivers without a dustcap but accessible center plug ("phase plug") one can cut a conical piece of acoustic foam (BASF/basotect in white or gray) to fill up the empty space , for absorbing any unwanted sound being reflected towards the microphone!
Now , where are the flat cone/disc drivers built by some heavenly creatures dancing in the moonlight
Like this ?
from Japan too. sorry have no experience with them.
but there exist some drivers like that from different mfgs.
http://www.fal.gr.jp/products/flat-c90/
http://www.fal.gr.jp/products/flat-c60/
http://www.fal.gr.jp/products/flat-c40/
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maybe too expensive and too exotic
PE has recently introduced something similar more rectangle-shaped ...
But Dayton Sig120 4-inch is quite shallow so reflected energy should be less than typical ...
A compromise is a compromise is a compromise so please don't get crazy about it!
IT COULD BE WORSE ..
You actually really don't want a flat membrane in circular mids and highs due to energy storage within the flat surface and the circular size. It will cause a peak in impedance like no other. I'm not saying you can't work around this, but it can create one huge thorny problem.
In bass it's fine as the wavelengths are long enough to be longer than the offending frequencies, and more often than not the Le rise reduces their effective properties.
The bending wave Tectonic drivers are not rigid flat diaphragms in the traditional sense and can get away with it.
In bass it's fine as the wavelengths are long enough to be longer than the offending frequencies, and more often than not the Le rise reduces their effective properties.
The bending wave Tectonic drivers are not rigid flat diaphragms in the traditional sense and can get away with it.
I am well aware of the design constrains but FLAT sounds so promising in the context therefor I kept it as an idol for the future!
The BMR is a can of worms
But the round 88mm unit designed by german tech designer and smart-ear KHF in Essen measures very good in the frequency domain! (not available for the public unfortuneable)
The BMR is a can of worms
But the round 88mm unit designed by german tech designer and smart-ear KHF in Essen measures very good in the frequency domain! (not available for the public unfortuneable)
@gedlee
Joseph Crowe kicks off his testing with the deadly GedLee metric!
Primer:
https://josephcrowe.com/blogs/electronics-testing-and-reviews/measuring-gedlee-distortion-gm
Landing page for testing of Electronics
https://josephcrowe.com/blogs/electronics-testing-and-reviews
Eg.
https://josephcrowe.com/blogs/elect...ngle-ended-triode-integrated-amplifier-review
Landing page for testing of Speakers:
https://josephcrowe.com/blogs/news
Eg.
https://josephcrowe.com/blogs/news/18sound-10nmba520-10-midrange-on-horn-no-1723
https://josephcrowe.com/blogs/news/...orn-for-grs-pt6825-planar-tweeter-test-review
Looking forward to seeing more of these types of tests in the future!
Best wishes,
Thanh
Joseph Crowe kicks off his testing with the deadly GedLee metric!
Primer:
https://josephcrowe.com/blogs/electronics-testing-and-reviews/measuring-gedlee-distortion-gm
Landing page for testing of Electronics
https://josephcrowe.com/blogs/electronics-testing-and-reviews
Eg.
https://josephcrowe.com/blogs/elect...ngle-ended-triode-integrated-amplifier-review
Landing page for testing of Speakers:
https://josephcrowe.com/blogs/news
Eg.
https://josephcrowe.com/blogs/news/18sound-10nmba520-10-midrange-on-horn-no-1723
https://josephcrowe.com/blogs/news/...orn-for-grs-pt6825-planar-tweeter-test-review
Looking forward to seeing more of these types of tests in the future!
Best wishes,
Thanh
Do you mean PE Flat Face ?maybe too expensive and too exotic
PE has recently introduced something similar more rectangle-shaped ...
But Dayton Sig120 4-inch is quite shallow so reflected energy should be less than typical ...
A compromise is a compromise is a compromise so please don't get crazy about it!
IT COULD BE WORSE ..
zaza-casino.net
.@HiFiCompass your work inspires and supports others:
More measurements:
https://www.justdiyit.com/comparatif-tweeters-bc25sc06-04-dx20bf00-04-sb26adc/
More measurements:
https://www.justdiyit.com/comparatif-tweeters-bc25sc06-04-dx20bf00-04-sb26adc/