EXTREMELY RARE - Ernie Ball MusicMan HD-500 Audiophile bass amplifier head; 480W; tube pre-amp / solid state power amp; direct out; tuner out; effects loop; speakon and 1/4" speaker outputs; comes with multi-function footswitch - mute, boost, EQ bypass, and CH1/CH2 (switching between 2 preset EQs), 2-space rack mountable. This amp was designed by Marco De Virgiliis before he launched the Markbass company; truly a piece of music history. This is a great sounding amp in great working condition. Also for sale locally and on reverb.com. NOTE: I have decided to include the homemade 3-space rack case that it's currently mounted in (see pics).