soviet made 20gds-3 speaker diffuser caps. spare parts from the speaker. dust cap

audio equipment cap dustproof shiny paper midrange speaker suspension diffuser repair 20gds3 20gds 15gd11 basket coil magnet ferrite vintage frequency revision upgrade soviet professional tweeter studio sound technology monitor driver music enjoy lowfrequency detail powerful obsolete brown 35as speakers preservation rectangular player subwoofer listen black riga device isolated radio