: Vintage studio gear can carry high voltages. If you aren't comfortable with board-level repair, it's safer to contact Tascam Product Support or a specialized audio repair shop.
This unit is a professional "rackmount" CD player typically found in broadcast and installation environments. Unlike consumer CD players, it features balanced outputs, RS-232 control, and robust transport mechanisms. tascam cd401 mkii service manual
If you're looking for a review of the CD-401 MKII itself (not the service manual), here are some general specs and information: : Vintage studio gear can carry high voltages