A friend has Dali Ikon 7s. They have both a soft dome and ribbon tweeter and three identical woofers. Yes, probably three times the cost of my M22s. But they sound as close as anything I've heard to the actual studio monitors of original recordings on tape. Some of this is due to the incredible high end with the combination ribbon and soft dome tweeters. I wondered if Axiom had ever considered ribbons. I would put the M22s up against most speakers, except for the high end, which seems a little closed. 'Course it could be other parts of my system, too. Any thoughts?

I believe that was brought up a year or so ago and Alan stated more-or-less that ribbon tweeters are in fact, not that accurate if I recall. Hopefully he'll fill us in....

That's pretty much what I've heard from Ian et al. So yeah, they've tried them, and they're using the things that their tests show sound best.

IIRC, the ribbon takes over from the dome after ~15khz or vice versa, there is a limit/filter they use to run the 2 tweeters. I could also be thinking of another companies design as well.

yes, I think you're right jakewash, they complement each other and are filtered or used with cross-overs to work together. It makes for really lively and stunningly accurate cymbals and percussion.

I think what they were really pointing out is that generally ribbon tweeters do not have as good as off-axis performance compared to domes. However, there are ribbon tweeters out there that trump down tweeters but generally you can get significant performance from a dome tweeter at very little cost which is why manufacturers tend to use them.

Ribbon tweeters have a tendency to be more expensive which is another reason why you see them only in so called "high-end" speakers.

I'm pretty sure that was it doc, off axis performance is not as good, which is why Axiom hasn't used them; as well as the cost factor.

Yes, I do recall that Ian mentioned in a past conference call that their tests showed one issue was the off axis was not near as good as the domes they use.

I don't doubt what Ian says, but it just seems interesting that
this article says just the opposite.

It's about car audio, but the theory ought to be the same. Under ADVANTAGES this is what it says concerning off-axis.

"Greatly improved horizontal off-axis response resulting in excellent high frequency detail retrieval, a more open and "airy" sound, and a wider/deeper soundstage."

Edit: But under DISADVANTAGES it also has this to say, that I just missed until now.

"Limited vertical dispersion. While this can be an advantage, it can also be a disadvantage. The tweeter must be aimed directly at the listening position, otherwise the spl will drop off. Can be a pain to work with if there are 2 people of different height sitting in the car."

So, good horrizontal, but poor vertical dispersion. It would then seem like both a dome and a ribbon would be the best of both worlds.

I dunno. Aside from the (usually) higher price of the ribbon, when you compare a well designed dome or ring rad tweeter in the $50 range from a company like SB Acoustics or Vifa for eg., they appear to have a much smoother freq response than charts of much more pricey ribbon tweeters in the $200+ range and nobody can hear anything anywhere near the freq the ribbons go up to, anything over 20khz is pretty much irrelevant.