ETS PMI-1U Instructions

PMI-1U Microphone Interface Instructions
The PMI-1U Microphone PC interface is for use with ETS PM1 series microphones or electret and dynamic professional
balanced microphones. Features include adjustable gain in two ranges,
adjustable low cut filter and Mute switch with indicator. Also features Internal DC-DC converter for
powering Electret mics without the need for an external power
supply.
Microphone Placement
Locate the microphone as close as possible to the area of interest in the space to be monitored. Do not mount the
microphone near air conditioning vents, light fixtures or electrical equipment. Most microphones operate optimally 3-5 feet
away from the subject(s) to be monitored. Microphones are still useable in the range of 5-25 feet but it is dependent on
the level of background noise in the area. Experimentation in the environment will determine what distances work best.
PMI-1U location and power
The PMI-1U interface box is designed to be placed near the PC or other USB compatible device. Once all settings are
made, the interface can be located out of view. All controls are recessed to reduce the possibility of accidental "bumping"
of settings.
Microphone Cable Run
Run a professional grade microphone type cable (preferred) or a 22 gauge, stranded, two conductor shielded cable
between the PMI-1U module and the microphone. Keep the cable run distance at or under 500 feet and away from AC
power sources, light fixtures and electrical equipment.
Microphone input
Connect the microphone per the wiring diagram in figure 1.
Phantom power and gain range switches
If you are using a phantom powered mic such as the ETS PM1 series microphones, turn the phantom power switch on
and set the gain range switch to the low position. If you are using a dynamic microphone, turn the phantom power switch
off and set the gain range switch to the high position.
Microphone Volume
Set this control for the best undistorted sound. Mid range for near field audio pickup and full Clockwise for far field pickup.
Experiment with the settings for the best result.
Low Cut control
The PMI-1U includes a low cut control for applications where pickup of low frequencies are less desirable. When turned to
the fully clockwise or 150hz position, ambient background noise will be reduced. If the full fidelity of the microphone is
desired, turn the control full counter clockwise or 20hz position.
Connecting to PC
In sound settings of windows, select PnP Audio device for microphone input. We suggest setting the mic volume to
midrange for near field applications and full volume for far field applications. Experiment with the settings for the best
result.