Hi Adam

To design a horn backround info is needed.

Issues
1. You dont require stereo horns unless you enjoy 2 monsters instead of one.

2. http://www.melhuish.org/audio/horn.html horn general info

3. http://www.geocities.com/sc00byd0159/TD.rtf Tom on the labhorn(lab12 basshorn )to get a few ideas.

4. http://homepages.paradise.net.nz/quadroph/30hzexpo.htm my original plans(note that this is old,and the woofer dimensions are actualy much more deeper and wider-i need to remove this site)

5. One needs to get intimate with HORNRESP
6. Large horn means bracing,and HDF/25mm MDF.
7. http://vincent.brient.free.fr/bass_horn.htm

Read the wiki links
Note that the excursion minimum,is not located at the F3 point like on a max flat ported box alignment!-because my horn design was extremely small mouthed. In the 30hz expo case,the low excursion point was ~38hz. With a long excursion driver like the B12/lab12 its less of a problem at sane SPL levels

We are talking 500litres for corner horn of 30hz F3.You could easily make it extend lower and trade a few db in efficiency ,say 101db/1watt at 24hz. Note that a large mouth is more technically pleasing even if i dont think it sounds 'better'

Cheers!
Mike.e

• Basshorn wiki