I have a back HDP-3 in nice shape. I've been using it for crossover/EQ/correction for my horn system for a few months.
Some of the front-panel lettering is starting to fade but other than that it's in excellent shape. (This wasn't disclosed to me when I bought it and actually I didn't notice it immediately.)
RCA only.
Includes Behringer microphone with long (25') cable.
No factory box but will pack well. Software included.
New ones are around $5K now I believe.
