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ETS SM4 4 Channel Listen Only Microphone Mixer / Switcher for SM1 Microphones
The ETS SM4 is a standalone 4 channel base station for monitoring 4 SM1 series microphones. This item has terminals for connecting and powering up to 4 SM1 series microphones, and it has two modes of operation. Either you can select one of 4 mode or mix in / out any combination mode.
This microphone mixer can connect to DVRs or tape recorders for live monitoring or playback, and it has a headphone jack for private listening.
Additional features of the ETS SM4 microphone switcher include simple 12VDC power input, a master volume control, a 3" full range speaker, and it has level controls for each individual microphone.