Recommend a HF waveguide for a 3 way XO at 5 kHz

[mitchba]

My 3-way uses digital XO to cross the midrange, which is a JBL 2380a 90x40 clone/Selenium D405 driver, at 5 kHz to a Selenium HM 11-25 60x60 exponential/BMS 4540.

I like the midrange sound and biradial coverage, No issues with the BMS 4540 either, but to me ears, the HF exponential horn pattern is does not blend well with the biradial mid.

The Selenium HM 17-25 60x40 biradial looks like a good candidate to match the pattern of the 2380a midrange. Plots look good: http://www.prodance.cz/protokoly/selenium_hm17_25_de25.pdf

However, in those plots, the very top octave has a large narrow dip in its response. I am unfamiliar with the compression driver used in the test, so I can’t tell if the issue is with the biradial or driver or both?

If not the HM 17-25, then what HF waveguide, using BMS 4540 driver, would folks recommend that would be good match with the 90x40 biradial mid?

Thanks, Mitch

 

[dumptruck]

The 2380a looks like it's still 90° at 5k, so why go to 60? Maybe I'm missing something but...
Dayton Audio H6512 6-1/2" x 12" Waveguide 1" Threaded | 270-318
(edit: P.S. it's a JBL PT clone, you've probably seen it before, Pyle clone also exists, probably one of the three available inside Canada).

 

[mitchba]

Thanks dumptruck, the HM 17-25 (and XT 1086) were recommended to me on another forum. The Dayton Audio device should match with the 2380a nicely. Cheers.

 

[CharlieLaub]

You could think about using one of the smaller waveguides shown on this page at DIYsoundgroup:
Other Waveguides DIY Sound Group
Looks like these are all threaded...

 

[mitchba]

Thanks Charlie, the DW-854B looks to have the same flare profile as the 2380a - could be a good match. I would need to use the screw-on adapter. Not sure how that would work out sound quality wise.

So many waveguides to choose from...

 

[badman]

Building A Budget (Super?) Tweeter Reaching the stratosphere! Article By Jeff Poth

The HM17-25 is a very nice performer, and works well for me crossed at about 2.8 k in this project. It did take some crossover doing to get 'er right.

An externally hosted image should be here but it was not working when we last tested it.

with a JBL 2206h

 

[mitchba]

Hey badman, looks good! I hope you don't mind me asking a question. From a subjective perspective, do you hear any beaming from the HM17-25? I suspect not, but...

So far the contenders are:

Selenium HM 17-25
Dayton Audio H6512
Denovo Audio DW-854B
SEOS-10
H290C

I have tracked down a number of posts with measures for each one, except the DW-854B, which ironically is the closest profile to the 2380a. All measure good. I wonder how I could go wrong choosing any one of them? ;-)

Merry Xmas.

 

[badman]

Hey badman, looks good! I hope you don't mind me asking a question. From a subjective perspective, do you hear any beaming from the HM17-25? I suspect not, but...

Well, if you mean pattern collapse, no, I'm getting very good constant directivity from the device. On the other hand, it's 60x40, so it's definitely a small sweet spot. For most rooms it'd be just enough to have both patterns cover a sofa, I think.

 

[mitchba]

Nice! The 60x60 HM11-25 I currently use covers the sofa area, which is all I am looking for, but being an exponential flare, the pattern collapses, or there is lobing, whatever, it beams, which is what I want to get away from. Thanks for letting me know your impressions as I assumed it would be similar to the mid 2380a biradial that I am using, which also has good constant directivity. Cheers!

 

[DorinD]

If not the HM 17-25, then what HF waveguide, using BMS 4540 driver, would folks recommend that would be good match with the 90x40 biradial mid?

Thanks, Mitch

Hi Mitch,
For a similar setup I'm happily using Eminence APT 150. You could give it a try because it's cheap and also can sell it easy in case you don't like it.
Regards,
Dorin

 

[mitchba]

Hi Dorin, cool project! I am happy with the BMS driver, but I see one can get the same horn as the APT-150, called EM-150S. Might give it a try. Thanks.
Best regards, Mitch