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I am recording with Zoom H1. I have two ATR-3350 lav mics. They are self-powered and have 3.5 mm (1/8") mono miniplug. I would like to combine them into one stereo signal such that the left channel gets audio from mic 1 and the right channel gets audio from mic 2. I tried a basic Y combiner and it combines the two signals but not into separate left/right channels.