HD-15 Kick Bin Horn Design
I am in possession of an unknown, unloaded speaker cabinet and an Eminence Delta-15LFC driver.
https://www.adamhall.com/shop/bm-en/archiv/2510/delta-15-lfc
The internal measurements of the said enclosure box are very similar in dimension to the outside measurements of a HD-15
Outside dimensions of a HD-15 - 578 x 578 x 472
Inside dimensions of 16mm MDF donor cab - 580 x 510 x 480
Most measurements are close enough but I want to make the horn longer and with a different radius.
I sketched out a quick box and horn with a radius of 500mm...... Attached below
Will this suffice....? Am I on the right track here.....?
I also read that I can reduce the volume of the driver chamber to make things a little more efficient.
Something like this
------>
I am in possession of an unknown, unloaded speaker cabinet and an Eminence Delta-15LFC driver.
https://www.adamhall.com/shop/bm-en/archiv/2510/delta-15-lfc
The internal measurements of the said enclosure box are very similar in dimension to the outside measurements of a HD-15
Outside dimensions of a HD-15 - 578 x 578 x 472
Inside dimensions of 16mm MDF donor cab - 580 x 510 x 480
Most measurements are close enough but I want to make the horn longer and with a different radius.
I sketched out a quick box and horn with a radius of 500mm...... Attached below
Will this suffice....? Am I on the right track here.....?
I also read that I can reduce the volume of the driver chamber to make things a little more efficient.
Something like this
------>
Last edited by a moderator:
Hello,
Take a look in the below thread
https://www.diyaudio.com/community/threads/would-a-small-folded-midrange-horn-work.382949/
Take a look in the below thread
https://www.diyaudio.com/community/threads/would-a-small-folded-midrange-horn-work.382949/
Correct; in theory and practice with compression horns you ideally want to reactance annul the horn, so near enough is to tune the rear chamber to the mean between the throat, terminus frequency, but a kick bin's terminus can be a variable depending on where in pi space it's located and/or whether stacked in an array, so if not much trouble, suggest trying it vs stock, which will roll it off higher with a 'faster' slope order.
I'd suggest the Delta 15LF is not appropriate for this style (or any) horn.
Some reading on Speakerplans, same place the HD15 plans are published
https://www.speakerplans.com/index.php?id=faq1
Some reading on Speakerplans, same place the HD15 plans are published
https://www.speakerplans.com/index.php?id=faq1
And why so..... The Kappa 15 LF gets lots of love over there.
Looks like I have no other option than to get my head around Hornresp.
What kinds of generalizations should I take from the changes I want to make......?
Looks like I have no other option than to get my head around Hornresp.
What kinds of generalizations should I take from the changes I want to make......?
Looks like your horn is slightly shorter, so response would roll off slightly higher.
A two piece straight plywood approximation of the curved horn would still give the same response, and would be easier to build.
If you make it more efficient, in the same sized cabinet, you will loose low end. Shorter horn: Less low end, smaller chamber: Less low end.
The Delta 15LF has T/S-parameters that suggest a BIIIIG rear chamber (highish Vas and high Qes), drivers with low Qes (around 0.2 - 0.25) will better suite the smaller chamber.
The Delta 15LF has T/S-parameters that suggest a BIIIIG rear chamber (highish Vas and high Qes), drivers with low Qes (around 0.2 - 0.25) will better suite the smaller chamber.
