The SE-120 is a speaker emulator DI load box.  It's purpose is to replace a speaker cab and microphone.  Instead of connecting a guitar amp to a speaker cab and using a microphone for recording or live performance you can connect to speaker output of your amp to the SE-120 and use the Filtered Output of the SE-120.

 

The SE-120 has an internal reactive dummy speaker load with 3 inputs (4,8 or 16 ohms).  It can handle any amp rated at up to 120 watts.  This reactive dummy load closely matches the impedance vs. frequency characteristics of a typical guitar speaker.

 

The SE-120 has a passive filter that mimics the frequency response of a close-miced speaker cab (Filtered Output).  There is a "Cab" control which sets the low frequency characteristics (1X12, 2X12 or 4X12) and a "Bright" control which sets the high frequency characteristics (similar effect to the positioning of a mic on the cone of a speaker).

 

The Unfiltered Output which can be used to send an unfiltered line or microphone level signal to a computer for use with software speaker emulation.

 

The Unfiltered and Filtered Outputs are unbalance 1/4" jacks.  There is also a balanced XLR output that can be switched between the Unfiltered and Filtered outputs.

 

A Ground Lift switch is used to float the ground on the XLR output.

 

The THRU OUT jack can be used if it is desired to use a speaker cab as the load instead of the internal dummy load.