Since kicking off their fall tour in Boston on Halloween the Disco Biscuits have toyed around with various aspects of their sound . Since Halloween percussionist Shawn Hennessey has toured with the quartet, while guitarist Jon Gutwillig has added a midi-keyboard to his mix. On Saturday the group also invited RANA guitarist Scott Metzger out for a cover of the Pinball Wizard and World Is Spinning during it second set at Baltimores Sonar. Hennessey, Disco Biscuits drummer and keyboardist Aaron Mager also engaged in a percussion-keyboard jam reminiscent of the latters semi-retired Moshi-Moshi project. The Disco Biscuits will perform at Millvale, PA,s Mr. Small’s Theatre Wednesday.