Yet another horn - timber frame, paper mache contour
The ply horn I recently built was possibly too much of a good thing:
As well as scaling it down, another goal was to try a different, more flexible construction method, to get a more ideal shape (a round throat).
Finally, I wanted to try using the finished horn (powered by a 4" driver) as a drop-in replacement for a 15" coaxial box. The coaxial is part of a speaker stack with two more 15s below, so my scaling was constrained by the width of the stack's bass box (465mm).
The construction pics speak for themselves:
- too big for the average domestic setting
- too much efficiency boost in the low mid range (challenging to get flat response with a simple high pass filter)
As well as scaling it down, another goal was to try a different, more flexible construction method, to get a more ideal shape (a round throat).
Finally, I wanted to try using the finished horn (powered by a 4" driver) as a drop-in replacement for a 15" coaxial box. The coaxial is part of a speaker stack with two more 15s below, so my scaling was constrained by the width of the stack's bass box (465mm).
The construction pics speak for themselves:
- build frame
- add paper mache
- paint / smooth (with food filler) / repaint
- deaden / stiffen the back with goo (plaster etc)
The last photo shows it on the coaxial box. I've built the horn 425mm across, so that it would be a good match with a 20mm timber border in place.
UPDATE 2015: It looks great, measures poorly. With this sort of horn, I'm discovering that the throat has to be just right, and this one is not.
UPDATE 2015: It looks great, measures poorly. With this sort of horn, I'm discovering that the throat has to be just right, and this one is not.