Super tweeter for FullRange Driver

My Bache Audio Tribeca’s use the Fostex FT96 EX-2 tweeter with a modified Tang Band wide band driver. I believe it’s crossed over around 8K. It’s a great sounding tweeter. You may get good results aiming it at the ceiling. Another option would be to aim it straight ahead into the room. Assuming that the Audio Nirvana drivers are positioned with some toe-in.

I had the Aperion Audio super tweeters on top of my 8" AN speakers and they did enough for me. They've got a decent amount of adjustment which is handy. 

I strongly 2nd @cedargrove's suggestion to watch the GR Research Tech Talk Tuesday video on You Tube, wherein Danny Richie explains and demonstrates all that is involved in adding a tweeter to a single-driver design. You'll be very glad you did!

I use Fostex T90 forward-firing with Altec 604E.
This combination works great.
I use first order crossover and Werner Jagusch auto-transformer to decrease output of super-tweeters. I use 1uF AN Copper capacitors. I’m not sure they are the best for this application but they work good.

Back of ceiling firing tweeters sound horrible!!! It completely destroys focus and sound-stage.
I don’t understand why some people use back of ceiling pointing of tweeters.
Probably people are too lazy to make a phase alignment of tweeters. When alignment is done properly, super-tweeters sound together with the main speakers.

Alexberger wrote: " Back of ceiling firing tweeters sound horrible!!! It completely destroys focus and sound-stage."

I disagree. Quite the contrary in fact when done right, and I can go into detail if you’d like.

The reason for keeping the supertweeter out of the first-arrival sound is so that it doesn’t screw up the phase of that first-arrival sound coming from your fullrange driver.

By increasing the amount of high-frequency energy in the reverberant field while leaving the first-arrival sound intact, you are fixing the tonal balance without degrading anything else, as long as the reflection path length is long enough. And a ceiling bounce usually is long enough at high frequencies.

Regarding whether or not to use a resistor or an L-pad, again that’s "play it by ear". DO NOT put an L-pad or any parallel resistor (or inductor) legs AHEAD of the crossover capacitor. Any resistor (or inductor) leg in parallel with any driver’s coil NEEDS the crossover capacitor in between it and the amplifier to filter out the rest of the signal, otherwise your resistor (or inductor) leg is seeing a full-power, full-spectrum signal from the amplifier.

If your crossover (more precisely, high-pass filter) is first order - i.e. just a capacitor - and if you’re just using a series resistor to adjust the level, then it does not matter whether you place that resistor before the capacitor or after the capacitor. Either way, the resistance that the capacitor "sees" is the supertweeter + the resistor.

Duke