A four string bass Jackson offered at least as early as 1984. The classic Concert Bass is a four string 34 inch scale neck-thru or bolt-on bass with 21 frets using a p-bass (J-20) neck pickup and a jazz single coil (J-150) or humbucking (varied) bridge pickup along with the J-2000 Bass preamp later. It has the ‘custom’ and ‘student’ options as did many classic custom shop Jacksons. During the 90s the Concert bass had three ‘Professional’ series variants and a ‘Performer’. In 1998 the line was drastically redesigned into several four and five string variants, passive and active. In 2002 it received another redesign as the CMG Concert bass and finally in 2012 using a similar look to the previous the current JS and X Series Concert basses.
Poplar body, neck-thru or bolt on maple neck. Ebony or rosewood fretboard with pearl sharkfin or dots. Binding optional. 21 frets. Pickups and control layout varies but J-20/J-150 PJ pickups were default it seems. JB-440 bridge. JE-2000 two band preamp as option. Finishes: varied.