Marshall JMP Paul Kelsall Year1968 Serial NumberS11010Watts50Folders Amp Archives Marshall 50 Watt Models Model #1986 or Model #1987JMP 1968 SN S11010 9Images 2 thoughts on “1968 Marshall JMP” This amp is actually JMP 1968 SN S11010 which has a folder in the archive already. It shows the amp in an earlier state compared to the existing pictures in the S11010 folder. Therefore, these pictures should be integrated into the correct folder so this folder can be deleted. Log in to Reply Updated with serial number. Log in to Reply Leave a Comment Cancel replyYou must be logged in to post a comment.