Fredenstein F607 is a monitoring module for the 500 series, manufactured by Fredenstein. The module can only be used in the Fredenstein racks.
Official description[]
The F607 is a high performance professional monitor controller, offering an effective monitor volume control for project and home studios in combination with a Fredenstein Bento rack. The F607 features a second unbalanced stereo input as well as mute, dim, mono and balance control functions. If used in a Bento D rack with, all parameters can be monitored on the LCD display