The 3hree was a three-zone version of the MRS.
Connection to the control pads
Looking into the rear of the unit, the speaker connections are:
|Right -||Left +|
|Right +||Left -|
Do not connect any speaker wires together.
The 3hree is compatible with sources products shown here.
The three must be configured with the 3hree configuration software which can be found here
This software may not run on versions of Windows after Windows 2000.