Originally Posted by
rdgrimes
The rating of the speaker, (16u, 8u, etc), is a different thing from the DC resistance measured with a meter. Drivers have a range of DCR that's considered normal, which you'll find in the spec sheets. 5-7u is fairly typical but each driver is different. Also good to note that a nominal DCR does not guarantee a functioning driver. But at least you know that the voice coil is not open or melted.
Presumably you are dealing with an amp that has a load rating, so you want to stay with a driver that's rated the same as the amp. Don't put a 4u driver on a 16u rated amp, or a dead amp might follow.