Dunlavy SC IV extra tweeter felt?

To dampen it. Most likely, the origional tweeters needed to be replaced and the exact same ones couldn't be found. So they installed new tweeters that were close, but not identical to the origional. The felt pieces were probably used to tune the new tweeters in an attempt to make them sound more like the old ones.

I found this from a Stereophile review: "with heavy felt around the tweeter"

Apparently the felt is factory original and part of the design. Leave it in place and enjoy those wonderful speakers...

-RW-

Thanks guys! I love them but was not sure why they were different from all the other SC IV versions.

The heavy wool felt surrounding tweeters and mids on John Dunlavy's speakers were intended to reduce refections and improve imaging. That was never attached to the drivers themselves.

So if the OP's tweeters have any felt attached to the domes then as Zd542 suggested, it was likely done on replacement tweeters rather than original. Four felt pads, even if very small, seem likely to damp/reduce HF response by a significant amount.