The 4-Channel SM Pro Audio Q-AMP Enhanced Headphone Amp delivers high-quality audio in a stylish, small-footprint unit. Upgraded to include SM Pro Audio's E-Series circuit design improvements, the Q-AMP demonstrates how SM Pro Audio's compact Value series of audio products has received a major revision in terms of appearance and performance. E-Series circuit design, component selection, and manufacturing offer an additional level of quality to the already successful HP4V. The headphone amp is housed in a stylish extruded aluminum external chassis that can be rackmounted using SM Pro Audio's RM-1 single unit rackmount adaptor. A single Q-AMP can be mounted in the center of the rack, or 2 Q-AMPs can fit side by side. SM Pro Audio includes robust connectors for all of the Q-AMP headphone amp's inputs and outputs.