Wizard of Kelts
diyAudio Moderator Emeritus
Join Date: Sep 2001
Location: Connecticut, The Nutmeg State
If the top of your speaker is flat-I don't know what the omnidirectional guide looks like-then you might consider the following tweeter arrangements.
A) Affix one tweeter to the front of the speaker enclosure, (one of the eight sides), and one to the back. This will give dipole tweeter radiation, which should share some characteristics with the woofer's omnidirectional radiation. Also, if the woofer is centered, then the time should be aligned.
B) If the top of the speaker is flat, then make a small enclosure with two tweeters facing opposite sides, and put it atop the omnidirectional unit. This would have the advantage of being able to be moved back and forth so you can experiment with imaging, time alignment, etc., before you find the right positon to fasten it to the top. Since you seem to be into different shapes, (octagonal woofer enclosure), you should be able to come up with an interesting looking dipole tweeter housing.
Just spitballing a couple of ideas around that might be worth consideration. Let us know what you decide.
[Edited by kelticwizard on 10-29-2001 at 09:48 AM]