These are such classic preamps. I remember one of the first live shows I ever saw, was being mixed with 2 of these coupled together.It has a real vibe to the sound, with very rich harmonics. Use the line input for re-processing your DAW tracks. Mix up to 4 mics and EQ the result with classic Baxandall-type hi and low boost and cut EQ.Many pictures of Motown Studios show this mixer in the racks, and The Black Keys use 2 of them in their studio.  This one came from a Hollywood film studio. No doubt with a celebrity background.It has all original parts. No plastic cap upgrades!Just the pure original sound.2 12Ax7 and 6FQ7 spare tubes included.