Hi Oltos,
I used a MiniDSP Umik-2 but I also have Motu M4 and Isemcon mic for measurements. As I related further on I traced the 4kHz resonance to a machine tool in the machine shop end of my room - a shield on my metal working lathe was resonating. I glued a stiffener to it and that killed the resonance. The last waterfall plots posted somewhere around here show I was successful. It was quite annoying. 😀
I used a MiniDSP Umik-2 but I also have Motu M4 and Isemcon mic for measurements. As I related further on I traced the 4kHz resonance to a machine tool in the machine shop end of my room - a shield on my metal working lathe was resonating. I glued a stiffener to it and that killed the resonance. The last waterfall plots posted somewhere around here show I was successful. It was quite annoying. 😀
One driver that is very affordable and apparently measured and auditioned most impressively was recently reviewed by Troy Crowe.
Here's Troy's measurements on the much loved Yamaha JA-6681B
Sadly, the replacement diaphragms had long ago went OOP, though that hasn't stopped Radian and these guys from pursuing the design of a clone.
https://www.diyaudio.com/community/...aha-ja-6681-compression-driver.163469/page-27
But though its response quickly rolls off below 10kHz, has anyone ever auditioned this driver in an A290 or TN4001 horn? If yes, please share your impressions, and what tweeter you would recommend, if any.
Sadly, the replacement diaphragms had long ago went OOP, though that hasn't stopped Radian and these guys from pursuing the design of a clone.
https://www.diyaudio.com/community/...aha-ja-6681-compression-driver.163469/page-27
But though its response quickly rolls off below 10kHz, has anyone ever auditioned this driver in an A290 or TN4001 horn? If yes, please share your impressions, and what tweeter you would recommend, if any.
Hi,
I don't remember who asked but my bi-radial is finished
Measurement of a 44cm with 2450SL (so 1.5").
The measurements show a very good Constant Directivity behavior, with flat DI, the fall and deep at 15/16khz is due to the breakup of the JBL 2450SL, not the horn.
It work very well on the 18Sound ND3T that breakup higher
A compression driver will loose his plane wave radiation behavior when the diaphragm breakup occur creating a cancellation at a precise frequency on their polar map, it rise up after if enough energy is sent (so particularly in CD horn).
I'm still working on a different way to build for make it lighter (it's very heavy and complex to build) and on an improvement of fins (again...)
I don't remember who asked but my bi-radial is finished
Measurement of a 44cm with 2450SL (so 1.5").
The measurements show a very good Constant Directivity behavior, with flat DI, the fall and deep at 15/16khz is due to the breakup of the JBL 2450SL, not the horn.
It work very well on the 18Sound ND3T that breakup higher
A compression driver will loose his plane wave radiation behavior when the diaphragm breakup occur creating a cancellation at a precise frequency on their polar map, it rise up after if enough energy is sent (so particularly in CD horn).
I'm still working on a different way to build for make it lighter (it's very heavy and complex to build) and on an improvement of fins (again...)
Hi, nice work. It would be interesting to see the throat section how you start into the horn and potentially the adapter.
Btw, just look at the ND3SN driver on my WN300ALO horn. Almost one octave lower horn loading!
https://sphericalhorns.net/2023/10/...ile-acoustic-loading-optimized-fc-300hz-horn/
It is quite simple to have an excellent directivity for a 600 Hz cut-off horn even without fins. But I have to admit that your data look good.
https://sphericalhorns.net/2023/10/...ile-acoustic-loading-optimized-fc-300hz-horn/
It is quite simple to have an excellent directivity for a 600 Hz cut-off horn even without fins. But I have to admit that your data look good.
Yes but your WN300ALO is a 60° horn, you don't need fins, and the horn is geometrically deeper as it's 60°, and 64cm wide.
I'm only 44cm (on this version) ^^ and 90° so a lot less deep but I can create whatever size or dispersion angle.
Do you have a polar map of your WN300ALO ? I found the 0/15/30, It looks like good and CD.
For cheap horn without fins but CD, whatever size, I use the X-Shape, opening 90 or 85.
1" 25cm + BMS 5530 version here but there is 33cm 1" and 41cm in 1.4", CD both axis :
I'm only 44cm (on this version) ^^ and 90° so a lot less deep but I can create whatever size or dispersion angle.
Do you have a polar map of your WN300ALO ? I found the 0/15/30, It looks like good and CD.
For cheap horn without fins but CD, whatever size, I use the X-Shape, opening 90 or 85.
1" 25cm + BMS 5530 version here but there is 33cm 1" and 41cm in 1.4", CD both axis :
Just look here for a 500Hz horn category:
https://sphericalhorns.net/2022/06/04/acoustic-loading-optimized-william-neile-horns-part-1/
Fins are not really needed for such "small" horns to get good directivity control. Anyway I generally wonder why people look for 90° radiation in a private listening environment. imo 60° is way enough and give you a better and deeper soundstage.
Using fins always introduce a new higher degree of complexity. What is the start arrangement and what is the end arrangement and the path length of each channel need to be equal in theory. So it always depend on the source what you get.
But you have chosen to place a lot of more fins in your design which reduces theoretically the differences between neighbor channels but it seems difficult to me how to manufacture these tiny fins and assemble them properly. If they become to thin you may introduce unwanted resonances in a high pressure region.
https://sphericalhorns.net/2022/06/04/acoustic-loading-optimized-william-neile-horns-part-1/
Fins are not really needed for such "small" horns to get good directivity control. Anyway I generally wonder why people look for 90° radiation in a private listening environment. imo 60° is way enough and give you a better and deeper soundstage.
Using fins always introduce a new higher degree of complexity. What is the start arrangement and what is the end arrangement and the path length of each channel need to be equal in theory. So it always depend on the source what you get.
But you have chosen to place a lot of more fins in your design which reduces theoretically the differences between neighbor channels but it seems difficult to me how to manufacture these tiny fins and assemble them properly. If they become to thin you may introduce unwanted resonances in a high pressure region.
Nice ok he is not really CD but very well balance, yes 90° is before 3m I would said, coverage depend mainly of listening distance and also acoustic (if side wall is close to speaker), I will use a 85° 45cm version for my usage that perfectly fit my listening distance of 3.5m (there his real acoustic treatment in absorption of front and back wall).
On the ND3 you can choose the adapter for what you prefer in HF, personally the first on is good for me :
Yes for complexity, it's not at all a DIYable horn, even the wood pass from - to + internal and external not a t the same point so even in a CNC with brand new rails on wood part it is very hard to construct, but I will change a little bit the way to do for make it easier, more printing and less wood/weight.
More fins put finger print higher, but there is a limit yes, the finger print become also a dilution device a this point, it can be use for distillate after the deep occurring by diaphragm breakup and improve the DI after 16khz (inaudible but nice on the polar pattern lol...).
The next improvement will again complexity fins (not the number) but well (for the little bump at 6/7khz with the ND3), I will print all this part entirely now, so...
On the ND3 you can choose the adapter for what you prefer in HF, personally the first on is good for me :
Yes for complexity, it's not at all a DIYable horn, even the wood pass from - to + internal and external not a t the same point so even in a CNC with brand new rails on wood part it is very hard to construct, but I will change a little bit the way to do for make it easier, more printing and less wood/weight.
More fins put finger print higher, but there is a limit yes, the finger print become also a dilution device a this point, it can be use for distillate after the deep occurring by diaphragm breakup and improve the DI after 16khz (inaudible but nice on the polar pattern lol...).
The next improvement will again complexity fins (not the number) but well (for the little bump at 6/7khz with the ND3), I will print all this part entirely now, so...