Hello,
I have been reading about Horns and wanted to start designing my first pair.
I see that most match the woofer size to the horn for constant directivity. I have been studying Earl Geddes designs and looking at best size compromise.
Because of design constraints I was wondering if I could use a 12inch driver pointed to the ceiling and cross over at 700 to 900 hz to a CD with a 15 inch waveguide. I would assume that I would lose low end directivity and that my directivity would start around when the CD takes over. Since I would be crossing over low would I have problems with this design?
I am planning to use a mini dsp for the crossover.
THanks for any help.
I have been reading about Horns and wanted to start designing my first pair.
I see that most match the woofer size to the horn for constant directivity. I have been studying Earl Geddes designs and looking at best size compromise.
Because of design constraints I was wondering if I could use a 12inch driver pointed to the ceiling and cross over at 700 to 900 hz to a CD with a 15 inch waveguide. I would assume that I would lose low end directivity and that my directivity would start around when the CD takes over. Since I would be crossing over low would I have problems with this design?
I am planning to use a mini dsp for the crossover.
THanks for any help.
In your design ... an up firing woofers directivity will not match up with the horn. In practice the woofer will lose all directivity.
A 12" on a small baffle is almost omnidirectional at 700Hz.
Newpaton2 - your concept would probably work OK, but you'll need to find a CD/horn combo that would be happy crossing over that low. In a domestic (not PA) application this might not be too difficult as you won't be pushing the CD too hard. In fact you might benefit from "cheating" a bit. If you use a larger 1" waveguide (like the famous QSC and it's clones) you'll find it starts to lose pattern control below ~900Hz. Since your bass driver has no directivity this might make the match OK. Your alternative is to find a big horn and probably use a 1.4" CD. Maybe the Eminence Textreme CD (which is OK with crossing over pretty low.
Newpaton2 - your concept would probably work OK, but you'll need to find a CD/horn combo that would be happy crossing over that low. In a domestic (not PA) application this might not be too difficult as you won't be pushing the CD too hard. In fact you might benefit from "cheating" a bit. If you use a larger 1" waveguide (like the famous QSC and it's clones) you'll find it starts to lose pattern control below ~900Hz. Since your bass driver has no directivity this might make the match OK. Your alternative is to find a big horn and probably use a 1.4" CD. Maybe the Eminence Textreme CD (which is OK with crossing over pretty low.
Ok, thanks HWEB. This is for domestic use. I was thinking of either the B&C DE250 or Faital hf108 CD in a 14 inch Oblate spheroid type horn. A 3d printed horn.
A cheaper alternative is Selenium D220Ti (now from JBL). However, only screw type available I think, a little work maybe.
All the best.
All the best.
Peerless makes a nice economy 1" CD. If you have the budget, IMHO any 1" CD from Radian will beat out the DE250 or HF108. But, of course, these are issues of preference.
Ok, I will keep in mind the Radian since they seem to have really good reviews. I have modified my design to create a proof of concept speaker that is much smaller and easier to expedriment with. I will use a 5.5inch midwoofer pointing upward or downwards and experiment with different waveguide sizes and crossover points. I can 3d print the waveguides and use a minidisp to simpify things with the crossover.
This build would be kind of like a linkwitz mini or pluto but instead of integrating the midwoofer to a a full range dipole configuration I will integrate it to a waveguide instead. My thinking is that even though the 5.5 midwoofer should be omni well beyond 900hz I could benefit from the constant directivity of a larger waveguide and cross over to a CD at around this frequency.
This build would be kind of like a linkwitz mini or pluto but instead of integrating the midwoofer to a a full range dipole configuration I will integrate it to a waveguide instead. My thinking is that even though the 5.5 midwoofer should be omni well beyond 900hz I could benefit from the constant directivity of a larger waveguide and cross over to a CD at around this frequency.
