Felt diffraction reduction advise

Same thing on my Snell Type E tweeters!

Here’s what I did with my AN-Es using jute mat from a carpet store. Works great, at least in my system/room.

https://forum.audiogon.com/discussions/audio-note-e-speaker-tweak-easy-effective-and-inexpensive-2

http://img.photobucket.com/albums/v260/TomBerry/8705A9AB-E436-4586-A811-051A068C187F_zpstuybpscn.jpe...

I have a question. If the creator of the speaker thought it needed felt, wouldn’t he or she have included it? It’s cheap and easy to apply. Or would it be added to change the highs in a unique situation?

Cut a couple pieces to match outside size of tweeter and perfect round cut to go around dome fairly close noticed slight change in sound stage. Then made another to stack that's when I notice loss of sparkle. Using blue tak so I can install and remove quickly for now. Maybe there is something to cut out being rectangle or star pattern, or stepping each layer with larger cut out like a horn. Does it matter how close felt is to button of tweeter? I'm going to just try strips for a square pattern and see what happens. I agree if there is a benefit why don't speaker manufactures use this, maybe cause it's ugly, if it works I don't care.

I have a question. If the creator of the speaker thought it needed felt, wouldn’t he or she have included it? It’s cheap and easy to apply. Or would it be added to change the highs in a unique situation?

Of course, and some do, some don't. I think this is partially a matter of aesthetics, but also whether the designer even thought to experiment with it. I don't think felt will always be desirable, but I do think it's a simple experiment you can do.
It's no different in my mind than playing with cables or toe-in.

Excessively deep foam/felt though becomes something else. Then we get into waveguide like behavior. If you are taking that approach you are approaching speaker redisign so might as well start from scratch.

I think Duntech or Dunlavy's used this deep felt approach as well.

Best,
E