ja mam yamahu, ted sem to meril a bylo to taky okolo 9,5 cm (mel jsem ho ale prilozen ke kytare)
Jmenuje se to Feedbackbuster, Feedback suppressor, Screeching halt, Soundhole cover.... hledat na ebay, u thomanna maji taky
nebo neco pekneho
http://www.lutehole.compak je par moznosti customizovanych DIY....nalepit pruhlednou podlozku z CD spindlu (jako kdysi Hladik v TV), anebo vyuzit starou podlozku pod mys....
Cheap Soundhole Cover:
Old computer mouse mats work great. Cut out two circles, one approx 1/2" greater diameter than soundhole, one approx 1/16" greater than soundhole, stick them together with contact adhesive (plastic mat face to plastic mat face), smaller circle fits into soundhole, larger sits on top of guitar. "Bob's your uncle" as Lauren would say.