Tweeter question

[Paul Joppa]

Here's a question for those with wider experience than I have - I know there are many of you here.

What's a good high frequency horn driver (and horn, for that matter) to cross over at 3kHz? This would be from a 5"-6" midrange cone.

It seems that most classic systems used either a 500Hz to 1200Hz crossover with larger horns (2" to 4" diaphragms), or they used a super-tweeter crossing about 8kHz. Sometimes both.

Presumably, the larger drivers just can't make it all the way to the top without suffering a little, and of the HF horns, only the 075 bullet was ever used as low as 2500Hz. I've heard that combo, and while it certainly sounds better than a D130 by itself (!) it still has some problems.

Thanks for any thoughts.

[Mr. Widget]

I assume this is for a home music system. What is the sensitivity of the mid driver?

If you can live with limited vertical dispersion, I would consider a ribbon tweeter. There are several good ones that will operate from 3KHz to way beyond most any horn and driver. (The 045Be excluded.)

Widget

[Alex Lancaster]

According to JBL, the 2404H can be xovered at 3KHz, I would go higher, at least 4KHz, 12 dB/oct.

[Robh3606]

Well the 2404 might work and there nothing written in stone that says you can't cross to a 1" compression driver at 3k although you would have to pad the daylights out of it. As long as the crossover is above the lowend cut off of the horn any 1" driver horn combo could work. So that gives you a whole range of choices.

Rob

[GordonW]

I would NEVER electrically cross a 2404 over at 3KHz. In actuality, JBL didn't either... if you plug the numbers for a typical 2404 crossover (say, that from the 4612), you'll find that even though the advertised crossover point is 3KHz, the actual ELECTRICAL crossover point of the high-pass filter itself, is 4500 Hz!

For a crossover in the region you're wanting, the closest things I can think of, would be like an EV ST350A or Eminence APT150. Either of these can be crossed over at 3500 Hz, second order... which, with a 5" midrange, should work quite well. Even with a 6", it shouldn't be that bad... not any worse than say, an L19 with a 2400 Hz crossover on an 8" woofer, really...

Regards,
Gordon.

[speakerdave]

Originally posted by GordonW
I would NEVER electrically cross a 2404 over at 3KHz. In actuality, JBL didn't either... if you plug the numbers for a typical 2404 crossover (say, that from the 4612), you'll find that even though the advertised crossover point is 3KHz, the actual ELECTRICAL crossover point of the high-pass filter itself, is 4500 Hz!

I agree. The 2404 is 10 dB down at 3k. I believe that in the 4612 (or the 4628, or both) where the nominal crossover is 3k the 2118 is allowed to run full to fill in the gap.

[Paul Joppa]

The 2404 comments were especially helpful, probably saved me from some expensive frustration!