I have the 2.8 cu. ft. cabinets with the AN cast frame 12 inch speakers and found that the treble response settled down noticeably after about 6 months. Some one here at the forum mentioned it might be the whizzer cone softening up some from vibration since it is paper construction.
I know you have the 10 inch AN speaker but when I used the filter circuits for the 12 inch suggested by Michael Chua here at the forum, it really smoothed some of the spikes. I used either a Class A SET tube amp or Class AB tube amp with them.
The P-Core coils from Parts Express for the larger values worked well and I adjusted the resistor value a little
I know you have the 10 inch AN speaker but when I used the filter circuits for the 12 inch suggested by Michael Chua here at the forum, it really smoothed some of the spikes. I used either a Class A SET tube amp or Class AB tube amp with them.
The P-Core coils from Parts Express for the larger values worked well and I adjusted the resistor value a little
My SWAG. As expensive as the ANs are, I've been reluctant to recommend kneading new whizzers to work the starch out of them [and add back some with spray starch if need be] as I was pretty much a 'broken record' about WRT all the 'el cheapo' 'FR' drivers we use to obsess over.
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