I just did the "filter mod" suggested by mochill on xb90ex. well, I got what he promised - highs are sparklier and I like it. the sound became a little bit more detailed, and it still has excellent natural timbre (I was afraid I'd lose it). also It became airy. oh, and as a safety measure, I used woman pantyhose stretched over the bore held by pure tension from the tip stems as a filter to protect these babies.
This is interesting... Can you please do a comparison to the likes of FX100/200?