I am looking for a speaker upgrade for my Fender Champ, and my options are limited since it uses only a 8" speaker. I have seen vintage JBL D208 speakers for sale on ebay and elsewhere. They look like a mini-version of a JBL D120, cast frame, large voice coil, silver dust cap, etc. Anyone have any experience with these speakers for use in a guitar amp? I am not looking for a hi-fi speakers, but an efficient speaker that has good clean sound would be nice for my mid-1970s silver face Champ.