The Radial Engineering MIX 2:1 is a simple yet highly useful mixer that passively sums two audio channels down to one. This enables you to easily sum the stereo outputs of a mixing voard, recording interface, or portable playback device down to one channel, or to mix any two mono signals together and balance their relative input levels.At the inputs of the MIX 2:1, both ¼" TRS and XLR connectors are available, with ground lift switches to eliminate buzz and hum from ground loops and ensure noise-free operation. Each input can be individually engaged or disengaged, allowing you to audition either signal before summing both together. A trim control is also featured on each input, so if you are connecting two separate mono sources (such as the outputs of two mic preamps), their levels can each be adjusted as needed to match their levels at the output. Both level controls can be completely bypassed, summing inputs 1 and 2 equally, and preventing accidental or unwanted level adjustments. The MIX 2:1 has a 180° flip on Input-2 to help solve phasing issues frequency cancellation. The passively summed signal then feeds a single XLR output that can be connected either directly to a powered speaker or the input of a console or recording interface.The MIX 2:1 is built with 14-gauge solid steel, featuring I-beam construction that prevents the circuit board from being torqued which protects against solder joint failure, along with a bookend design that protects the level controls and switches. A military-spec circuit board and high quality components help maintain the integrity of your audio quality, without distortion or phase shift, resulting in completely transparent passive summing.FeaturesMixes two channels to a single mono outputIndividual level controls can be bypassed when not inuse¼" TRS and XLR inputsCompletely passive, no need for powerExtras: Level Control with defeatOn/Off switch for each inputSpecificationsAudio Circuit Type: Passive mixerFrequency Response: 20 Hz to 20 kHzNoise Floor: -113 dBuDynamic Range: >133 dBMaximum Input: >+20 dBuGain: N/AIntermodulation Distortion: >0.002% @ 0dBuTotal Harmonic Distortion: >0.005% @ 0dBuCommon-Mode Rejection Ratio: >80dBPhase Deviation:0° @ 20 Hz0° @ 1 kHz+2° @ 10 kHzInput Connectors: 1/4", XLRInput Impedance: 8 kΩOutput Connector: XLROutput Impedance: 1 kΩSwitches: 180° switch, ground liftGeneralPower: Passive, no power requiredConstruction: 14-gauge steel chassis and outer shellSize (L x W x H): 5" x 3.25" x 1.85" (12.7 x 8.3 x 4.7cm)Weight: 1.48lb (0.67 kg)Conditions: For use in dry conditions between 5°C and 40°C Radial Engineering MIX 2:1 2-Channel Stereo to Mono Mixer, Passive, TRS and XLR Inputs, XLR Output.