Originally Posted by coctostan
Jack, what do you prefer about the 4552? They have almost identical FR's and the 2nd and 3rd harmonics are pretty close. My understanding is that they are pretty close to the same short of the neo magnet. Of course I'd generally prefer neo for pro use, but it doesn't matter much in the home.
My experience (and that of a few others who are well respected)is that two non-titanium CDs, on the same horn, both playing over their comfortable range, EQd to identical targets are nearly indiscernible. Of course people rarely compare them like that and instead it is in different rooms or with different horns or with crossovers designed by different people.
Short answer, the 4552 has a higher flux density.
This is because with neo you can focus the power in the gap more. But there is a bit more than that to it.
As mentioned with the coax drivers, neo has the potential to have less flux variation over the power band.
And this is how one of the design engineers at BMS use it. So I am told. There is really no data, or sheets to show it.
I do know that I sent some drivers to a guy to measure and listen to. It turns out that he was using EV drivers.
He said the neo and ceramic from EV sounded identical. I am guessing EV voiced them the same (flux density), so that they could sell replacements, to people that were using their vintage gear.
Just a guess, no real knowledge.
For me the difference is dynamics. In a listening test we did over 12 years ago, I had just purchased some td-1's. We tried the 4548 vs the driver in them.
(This was before neo magnet BMS, or double wound Voice Coils.)
One of the most revealing things was pointed out by a drummer that was there. (I tend to listen to vocals first.)
He showed that with the BMS you could hear the drum stick hit the ride cymbal, and with the stock driver you couldn't. The frequency response had nothing to do with it.