It hard to fix in a OB as you cant stuffing the box to damp.
There is various xovers fans that like to put a notch filter.
An suggetion is toe in 30/40 deg, I could just put a cloth or
2mm felt as screen in front of the 1808 as a sock.
Thanks for the suggestion. Allready running the 1808 toed in about 15 deg and I like it as that, but there is still some HF that has to be tamed. Yesterday I was reading about a guy in here that knows how to tame the 1808 using x-over parts. It looks very good on paper the stuffe he did to the 1808. Did send him a PM about the filter parts and price for shipping to Denmark..... still waiting for reply.
Here is a link to it :
https://www.audiocircle.com/index.php?topic=158567.new#newThe suggestion about using filt I have done before with some cheap FR drivers and the filt did some good things to the FR - used it on the back side of the FR ( inner frame and out side on frame )
The way Danny Richie tame the 1808 ( see link above ) I think is the way forward.... just don’t know if it is useable for OB but I’m sure Danny can tell me that.
BR
Alex