How to add brightness to sitar with "bandh" (closed) jawari

Hi, I have a sitar conditioned by my teacher and one of the things he worked was jawari. He mades jawari the closed style, but I like the brighter sound like the Ravi Shankar sound (which is more open according to http://raganet.com/Issues/1/jawari.html).
Without modifying the jawari myself, is there any other thing that can be adjusted so that it sounds brilliant, brighter? I saw in concerts that some sitarists put "things" between strings and the jawari or between strings and the "meru" (is it called that way where strings are holded before the tuning pegs?). Is there something simple like that that I can do to raise/lower strings and bring more brightness to the sound?
Thanks, best regards.
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