View Full Version : K2-S9800's 1500 AL 15" driver Q

03-04-2006, 04:18 PM
I know alnico is an excellent performer (when fresh). I read the sticky about ferrite and alnico. I know why we no longer use alnico.

My questions is: Why (and how) does the 15" driver of a new K29800 employ alnico? I was under the impression we could no longer obtain it. What gives?

I tried to search for my answer in the forum to no avail. If this is posted elsewhere- I apologize.

Titanium Dome
03-04-2006, 04:22 PM

Don McRitchie
03-04-2006, 04:26 PM
Alnico was only unavailable for about a year while the civil war raged in Zaire. Afterwards, it was back on he market, but at much higher prices, which remains true to this day.

The following extract from the 1500AL article on the site explains what JBL decided to develop this driver:

Nonetheless, the ferrite developments led to an interesting question. What would happen if the same level of innovation applied to ferrite designs were applied to Alnico motors? As described above, Alnico starts off with a number of intrinsic advantages compared to other magnetic materials. By leveraging these advantages, it should be possible to achieve new levels of accuracy.

The entire article is here:


03-04-2006, 04:27 PM
did u c this? http://jbl.com/home/k2_story/k2_tech1.aspx

No, I didn't. Thanks!

EDIT: Just read it. This is my favorite line:
But, because Alnico magnets tend to demagnetize at high power levels, they've all but disappeared since the 1970s, when amplifier power outputs increased ramatically.

Two things-
1. Is that really the reason we stopped using Alnico? or was the whole African uprising made up? :blink:
2. I assume the last word is "dramatically", not "ramatically" (....unless, 'ramatically' is a tech term that would completely explian the situation..).:p

Don, you posted at the same time I posted this. Completely answers my question(s). Thank you!!

Moderator may delete. Thanks guys!

Steve Gonzales
03-06-2006, 10:35 PM
Luv the new avatar ;)

03-07-2006, 04:36 AM
Luv the new avatar ;)

...finally found one I luv too. I threw it together in MSpaint and it made me laugh. It's a keeper. Thanks, dude!
Of course, the "eyes" are 1500AL from a K2. I knew you'd appreciate the disco cateye nose and 2397 smile..