ken kantor
Fowl Humor
how long is the average life span on these? how can you tell if they are bad or dried up? thanks...
There are hundreds of types of magnetic fluid, each of which has a different life span under different conditions. Also, not all driver designers know, or have the freedom to apply, best practices. Properly selected and used, a fluid-filled tweeter can last 40 years with very little degradation. On the other hand, many people find their tweeters shot after less than 10 years. (When mag fluids were first introduced, some over-enthusiastic manufacturers erroneously used water-based formulations and/or paper formers, which lasted weeks or less.)
The easiest way to check the condition of the fluid is to run an impedance curve and look at how much bump there is around resonance. Ideally, this should be compared to both a working reference and a non-filled unit. Still, simply looking at the curve can usually tell you a fair amount.
-k