Just as an example, I think the ff. high-efficiency speaker system may be further improved upon (even if just frequency response-wise) if FIR filters were to be used:
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Yeah, and from here:
http://www.audioheritage.org/vbulle...5-D2430K-compression-driver-information/page3 from our own pos, the compression driver from the M2 is compared to two other drivers in a different horn, with no EQ, just a high pass:
Does anybody doubt for a minute I would have trouble finding about
one million examples of speakers with low sensitivity that have very rough frequency responses? Could I not then use those (many) anecdotes to make the opposite argument? You don't "make a Law" with anecdotes.
Whether buying, simulating or building and testing, Hofmann's Iron Law makes sense to us because those things are all interrelated. And try as we might, it's very hard to get around or even bend much. So we all accept it and don't mind it being called a "law."
There simply is no such relationship of which I am aware between sensitivity and "smoothness of FR." If you have one based upon something other than anecdotal examples, I'd love to hear it. BTW, sensitivity is quite often limited by the base output even with speakers using dome tweeters, so even if one were to accept that all compression drivers were garbage, the "new law" still wouldn't hold up. This can be seen in many product lines where the big tower uses the same tweeter as the small bookshelf, has higher sensitivity and might have a better frequency response as well.
Interestingly, this has turned to a conversation of compression drivers...I like it.
I'll throw in my opinion. For those who asked, for some applications,
yes, they are needed--even for "home use." As some above have pointed out, there are some very real practical limitations of dome tweeters at high levels.
There's also the practical
experience many have. As has been discussed here many times in many different threads, beyond paper specs and data to which we have access, it is commonly observed when people experience speakers with big horns and compression drivers that they still "sound good" at SPL's where speakers with dome tweeters not only don't sound good anymore, but may actually be painful. This is so commonly observed (nearly universal?) we can't all be imagining it.
It's even mentioned in Floyd's book several times, where in a nutshell he's saying if you have a big room and/or simply want high SPL much of the time, you want horns with compression drivers. You just do. He chalks it up to lack of power compression and distortion, but doesn't give any specifics beyond that.
Maybe if they got the stop conditions of AES75 right and manufacturers/testers widely adopt it, we'll have a lot of data to help make sense of the realistic output levels of types various speakers in a few years.
Since the JTR's are generally used for home theater, here's another hurdle those thinking dome tweeters can do just fine may not have considered. If one does a "proper" setup, that means putting the speakers behind the acoustically transparent screen. Depending upon which screen you choose and how your installation goes, you may find your acoustically
translucent screen knocks your output down by 6, 8, even 10 dB on the top end.
That's OK, that's what EQ is for. Just boost it back up! Fixed! Well, if your speakers are using dome tweeters, you have a decent sized room and like to watch at a decent level and you've eaten away that much headroom...OK, but you may be well advised to have a pile of replacement tweeters on hand.
