These are automatic microphone switching units, that sense the presence of someone in front of the microphone. Equipped with an infra-red sensor, the units plug between the microphone and microphone connector.
The Optogate unit switches the microphone on when someone is in front of it, and off again when they are no longer there. A red status LED indicates when the microphone is switched on. They help eliminate unwanted background pickup by unused mics on stage, and reduce the possibility of feedback.
The sensitivity is adjustable via trim pot, so can be set for optimum operation for the type of application - for example close-mic music vocals will benefit from a lower setting than conference sound reinforcement applications. All Optogate models are powered from 48V phantom power, no AC adapters or batteries are required. Inputs are XLR 3-pin female, outputs XLR 3-pin male.
They are available in a number of different housing configurations, all share the same technology and electronics.
Available in three versions, PB-05E, PB-05M, and PB-05D, PB-05 is an in-line device that has been designed to be plugged directly onto the microphone with the infra-red sensor facing the microphone and user. PB-05 is intended for vocal microphones, acoustic instruments and talkback mics. All models are compatible with dynamic microphones or microphone requiring phantom power up to 10mA current consumption.
| PB-05M |
This version mutes the mic channel (-42dB) when activated. A bypass switch allows the user to disengage the optical sensor. |
| PB-05D |
This version ducks the mic channel (-16dB) when activated. A bypass switch allows the user to disengage the optical sensor. |
| PB-05E |
This economic version is manufactured from plastic and mutes the mic channel (-42dB) when activated. There is no bypass switch. |
Notes: (1) depending of the type of reflection surface. (2) With 150 Ohm microphone. (3) Daylight/artificial light.
Optogate PB-07 is similar to the PB-05, and shares the specifications of PB-05M, however the sensor is on the flat side and therefore more suited to gooseneck or podium microphones. On the rear is a 4mm threaded hole to fix a clip that can then be installed on a mic stand stem to be somewhat hidden from view. PB-07 will then detect the presence of someone near the stand. Dimensions (LxHxW): 68 x 35 x 21mm.
Optogate PB-06 has been designed for use in conferencing applications. Like PB-09 a combination of optical gate and push button allow the user to mute the microphone by proximity or touch. Two 50cm fixed cables, 1x male and 1x female, are terminated with balanced 3-pin XLR, and enter the main unit via screwfit glands. the case is manufactured from 1.2mm steel and powder coated in white finish. Attenuation and other specifications as per PB-05. Dimensions (LxHxW): 40 x 25 x 12mm, excluding fixed cables.
PB-09
Optogate PB-09 is integrated into a microphone table stand. As with the other models, it will switch on the microphone if someone is in front of the mic. The stand base has a ‘mic on’ button that can be used as ‘push-to-talk’ or ‘mic latch’ switch; these different functions are user programmable with three hidden DIP switches. The mic circuit switching is effectively noiseless, and is fully isolated from the control circuit. A red status LED provides indication to the speaker that the mic is switched on. PB-09 is powered from P48 phantom power and can be used in connection with both dynamic and condenser mics. The phantom power passes to the microphone. This unit provides a particularly effective noise-reduction facility for conference and meeting-room applications, removing the need for automatic mixing facilities.
The base is cast iron, and has three rubber feet to provide isolation. Dimensions (LxHxW): 125 x 31 x 90mm. Weight 1.2kg.