ETS SMI-1CP User manual

SMI-1CP Microphone Interface Instructions
The SMI-1CP is a single channel interface for use with all SM1 series microphones. It provides a convenient way of
supplying power to the SM1, installer friendly termination of the cable runs and a standard RCA, 3.5mm of flying leads
audio output connector. The SMI-1CP is designed to be used where 12-24Vdc power sources are readily available. The
SMI-1CP then easily connects to recording equipment such as DVRs, IP cameras and audio recorders. Note the audio
output signal of the SMI-1CP is “line level” (0dbm).
SM1 Microphone Placement
Locate the SM1 microphone as close as possible to the area of interest in the space to be monitored. If a large area is to
be monitored, locate the SM1 in the middle of the room. Do not mount the microphone near air conditioning vents, light
fixtures or electrical equipment. The SM1 should be placed as close as possible to the subject(s) to be monitored. The
SM1 is useable at distances of up to 25 feet but is dependent on the level of background noise in the area.
Experimentation in the environment will determine what distances work best.
SMI-1CP location and power
The SMI-1CP interface box is designed to be located next to a DVR or IP camera. Connect the +12V- input to an
available source of 12-24VDC.
Cable Run
Run a 22 gauge, stranded, two conductor shielded cable between the SMI-1CP interface and the SM1 microphone. Keep
the cable run distance under 1,000 feet and away from AC power sources, light fixtures and electrical equipment. See
Figure 1 for connection diagram.
Mounting
The SM1 can be surface or flush mounted on ceilings or walls. For flush mounting, cut a 2 ¼” by 2 ¾“ hole in the wall or
ceiling tile to allow room for the circuit board and mount the SM1 to the surface with screws. For surface mounting,
purchase the SM1S surface mount adapter or use a single gang electrical box.
Adjusting the SMI-1CP Level
It is recommended that you set the SM1 gain to maximum and use the SMI-1CP level control for best sound results as
described below in “Adjusting the SM1 gain”.
Adjusting the SM1 Gain
Start with a midrange setting of the gain control on the SM1. Adjust the control + or – for maximum clarity. If the sound at
the amplifier is distorted, rotate the control towards the – mark (counter- clockwise). If the volume at the amplifier is too
low, rotate the control towards the + mark (clockwise). Set “Vol range” switch per instructions below.
The “Volume Range” switch should be set to the “LO” position when using the SM1 with IP cameras that utilize
“microphone inputs” also known as “Mic. Level” inputs. This sets the maximum gain of the SM1’s pre-amp to x14. The
switch should be placed in the “HI” position when using “Line level” inputs of DVRs and IP cameras. This sets the
maximum gain of the SM1’s pre-amp to x196.
The SM1 is shipped with the gain set at midrange. If the sound at the “head end” is distorted, rotate the control towards
the – mark (counter-clockwise). If the volume at the “head end” is too low, rotate the control towards the + mark
(clockwise).
Setting the SM1 Hi-Cut/Lo-Cut Switches
The normal frequency response of the SM1 microphone is 500-13Khz. When both turned on”, The “HI Cut” and “Lo Cut”
filters set the SM1’s frequency response to 900-6Khz . Enabling one or both of the filters is useful when background noise
needs to be further reduced and intelligibility of speech emphasized. We recommend experimenting with the switch
settings to achieve the best acoustic result for your application.

Figure 1.
Caution
It may be against the law to install this microphone kit in certain environments. It may also be against the law to record
conversations of the person(s) being monitored without their knowledge. It is the responsibility of the installation company
and end-user to determine if the application of this product is legal. These laws vary from state to state. If you are not
informed on these matters, consult a qualified attorney or contact the appropriate state agency. A sticker is provided with
this kit for the applications where notification must be posted.
Warranty
All ETS products carry a one year parts and labor warranty. This warranty does not cover damages as a result of misuse,
improper handling of the unit or exposure to extreme temperatures or moisture. At its discretion, ETS reserves the right to
repair or replace this unit under the conditions of the warranty. If you experience problems with your equipment call ETS
at: 505-888-3923 to obtain a return authorization number. Equipment requiring repair beyond the warranty period or units
that have been damaged or are not covered under the warranty can be repaired by ETS for a minimal cost under most
conditions.
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