Processing and Control for Professional AV Installations
Legacy Hardware

306 Preamp / Ducker

Like the other units in the Symetrix 300 series, the 306 is designed to provide extremely versatile controls within a streamlined, half-rack sized housing. Once installed in a paging/foreground music system, the 306 offers precise adjustments to automatically reduce the gain of a program signal when paging occurs. This allows the page to be heard clearly, without having to compete with program material such as audio from a CD, radio, TV or other sources.


There are two separate AC supplies coming out of the PS-3: 8.5 VAC @ 1A and 34.5 VAC CT @ 250mA. Pinout is as follows: 8.5 VAC on pins 6 and 1, 17 VAC on pins 7 and 3, center tap @ pins 4 and 5 are connected to earth ground. This is when viewed at the end of the PS-3 7-pin DIN plug.

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No, the only option would be to use a 12VDC to 117VAC inverter with the supplied PS-3 inline power supply.