This collection goes beyond just 'jam tracks.' Jammers know that you can add one more layer to just about anything.
So here are my picks for the coolest stuff to play over, and some of the best music to learn from. Through repeated spontaneous interaction, you can learn the substance and nuance of music. Each section features backing tracks and songs in a variety of keys, styles and tempos.
Em G C D -- This one's very popular on Youtube. Slow, Pink Floyd styled. Drums, bass, guitar, synth strings. Use Em pentatonic, Em scale, G major scale, Em7 arpeggio, G major 7 arpeggio. Also G pentatonic (G, A, B, D, E, same notes as Em pentatonic.)