Ferrofluid tweeter


I recently purchased a pair of B&W P5 speakers that were made in 1997. After making sure all the old ferrofluid was removed entirely, it was time to add the magic. While adding the ferrofluid, I purposely put 60ul into on tweeter and 100ul into the other. One thing for sure, it made a huge difference in voice clarity, no more muffled sounds coming from the tweeters.

There is a slight difference between the tweeters because of the different amounts of ferrofluid used. The tweeter with 60ul is a little brighter than the 100ul, but can’t decide which one I like better. Once I decide which one to go with, I’ll even the two tweeters so they will match in sound.

Has anyone used less than the required amount of ferrofluid in a tweeter, and would there be any harm in doing so?

The tweeters I have are 1 inch and require 100ul.



prestons

Showing 1 response by shadorne

Pretty much all dome tweeters use ferrofluid. In addition to above points by timlub, it also helps align the voice coil. Small voice coils in a tweeter are susceptible to rocking motion.

Ferrofluid is a cheap solution to building a tweeter that will perform well for about 5 to 10 years. Usually performance declines audibly after 5 years and sometimes as little as 2 years. Replacing the ferrofluid is a good idea on 10 year old tweeters.

ATC now make all their transducers in house and their soft dome tweeter is one of very few that do not have ferrofluid. In order to overcome alignment or rocking issues they use a double spider to stabilize the voice coil and to overcome heat build up the manufacturing tolerances are very tight - costly to make.