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SpankingVanillaice
09-26-2008, 08:46 PM
Does Neodymium magnets pack more magnetic energy per ounce than conventional Ferrite, Samarium Cobalt or Aluminum magnets? Also does speakers that has Neo magnets have more powerful bass and clear treble then speakers that has magnets like Ferrite?

Mr Peabody
09-26-2008, 09:55 PM
Neodymium is a stronger magnet. I've only noticed it being used in smaller applications like headphones, microphones or smaller drivers like tweeters. I'm not sure if they use Neo for larger magnets. I'm not sure how Neo effects sound in speakers as compared to a non-Neo. I remember though when Electro-Voice came out with their Neodymium line of microphones they did blow anything on the market at that time away. We used to call them the "voice of god" microphone.

SpankingVanillaice
09-27-2008, 05:29 AM
I did see speakers that use Neo on all drivers like the JBL PT800, JBL LSR4300 series and the JBL LSR6332. There are other high end speakers I seen that use Neo magnets too.

basite
09-27-2008, 06:51 AM
neodymium magnets are indeed more magnetic, so the magnets can be smaller. Downside is that in applications like speakers, they do tend to run 'hot', so they need to be cooled...

there are a couple of brands that use neodymium magnets in high end speakers, but mostly in tweeters, sometimes mids too, mainly because there a smaller magnet is more practical to work with. If you have a 10 inch woofer on the other hand, with a normal sized ferrite magnet, it would be useless to replace the ferrite with neodymium. Because when the neodymium magnet has to have the same magnetic strength/force as the ferrite magnet, it would be considerably smaller, making it impractical to work with, they'd have to use a tiny voice coil so it would work with the magnet. If they'd make the neodymium magnet the same size as the ferrite one, the magnet would be too powerful...

some woofers that otherwise would need gigantic ferrite magnets now use neodymium, because then the magnet size is practical to work with, and it makes the motor structure considerably smaller, these woofers are mostly used in car audio...

neodymium is a tad more expensive though as ferrite...


then, the sound difference...

Most of this difference is also only noticeable with the tweeter, because the tweeter mass has to be low, and when you can use a smaller motor structure, then it's even lighter, resulting in a more detailed & 'faster' response...
differences are bigger with real high end audio though...


Keep them spinning,
Bert.

SpankingVanillaice
09-27-2008, 08:01 AM
Well I guess I could ask this but is the reason why my new Sony SRS-ZX1 speakers that my best friend got me have Neo since it's only a 57mm driver? Meaning it's a small full range driver. Also I guess it is true that Neo does cost more since speakers that use ferrite usualy cost less. I also would like to know is that is a 57mm driver that is full range that is using Neo will make the sound more clear or better in the highs than a speakers that is 57mm but using ferrite?

basite
09-27-2008, 08:59 AM
I also would like to know is that is a 57mm driver that is full range that is using Neo will make the sound more clear or better in the highs than a speakers that is 57mm but using ferrite?


depends on what driver we're talking about, in your case (pc speakers, even though they cost 399,99), I think the performance difference would be marginal at most...


in your case, it's probably to save space, the speaker thingies ain't that big...

Mr Peabody
09-27-2008, 03:21 PM
What would really rock is a 57 pound ferrite magnet, now you are talking.

SpankingVanillaice
09-27-2008, 06:21 PM
I forgot to ask this but is Alnico a better magnet than Neo or are they the same?

filecat13
09-27-2008, 07:01 PM
At one point in time, an AlNiCo was better than most, but after the African conflict that closed off access to most of the world's supply, engineers worked hard to bring Ferrite magnets up to the same levels of performance and efficiency. These days, it's hard for AlNiCo or Ferrite to beat a Neodymium magnet for lightness and power.

There were some concerns early on that Neo magnets would fail under intense heat, specifically by losing their magnetism, but there is no indication that this is true. A Neo magent is strong enough to destroy the cone before it overheats.

For Neo magnets to be widely available in mid-level consumer products, they have to be price competitive, and Ferrite still wins that battle, though the gap is closing.

Newer AlNiCo magnets are now available, but they have a premium cost and there are concerns that they will still demagnetize under stress, just as the originals did.

Florian
09-28-2008, 11:56 PM
If you buy an Apogee Synergy or Definitve you get about 300lbs or more of them..... ;-) They only use such magnets.

Cheers

Correction: The Synergy uses those, the Definitive uses "rare earth magnets"....whatever that is. but it gives a huge ribbon speaker close to a 100db efficency ;-)

Mr Peabody
09-29-2008, 07:20 PM
Florian, have you heard any of the T+A gear? If so, what is your impressions?

filecat13
09-30-2008, 02:48 PM
I've heard of T&A. :eek6:

S-Val-ice: As you note, my JBL Performance Series drivers all have Neodymium magnets, from the tweeter, 4" midrange, and 6" midbass, to the 8" woofer. They're all Ti inverted domes, too, except the tweeter which is a regular dome. The 14" woofer is a more traditional Aquaplased cone and Ferrite magnet with a 4" edge wound voice coil.

You'd have to hear them to believe them, but pound-for-pound they're some of the most wonderful drivers I've ever heard. They easily outperform all of my bigger, more well-known, vintage JBLs.

Florian
10-02-2008, 01:59 AM
Nope, havent heard them yet. But i must be honest with you, i have stopped listening to HIFI gear in general after my aquisition of the Apogee Grand. My system is just stable, no need to listen to other gear. I dont even know any of the latest news on anything. I am pretty out of date.

GMichael
10-02-2008, 05:13 AM
Nope, havent heard them yet. But i must be honest with you, i have stopped listening to HIFI gear in general after my aquisition of the Apogee Grand. My system is just stable, no need to listen to other gear. I dont even know any of the latest news on anything. I am pretty out of date.

If I had your system, I wouldn't bother with other equipment either. Might even stop listening to music in the car. Wait, no, that's not true. But there'd be some serious upgrading going on for the auto.