St. Mark’s D70 DSP Effects Guitar Pickup. Not only is the St. Mark’s D-60 D-70 a preamp and chromatic tuner, it is a full signal processor. The 16 bit effects processor with digital 3 band EQ and reverb includes four sets of separate effects: delay, chorus, flange and tremolo. Another feature on the St. Mark’s D-60 D-70 is the user memory. There are nine different settings for user performance. This device is a great asset to an already great guitar。