Musicians familiar with the exceptional performance of the BP1 Bass Pickup System have requested a design that would allow them to use the Rice Audio® pre-amplifier with sensors provided by other manufacturers. The PA1 uses the same circuit that has worked well for the Bass Pickup System but adds three subminiature jacks to provide a more flexible design.
The current mode input can only be used with a low level current mode signal source such as that generated by a magnetic or piezo-electric sensor. Do not connect a voltage mode signal from another pre-amplifier as it will overdrive the input and possibly damage the amplifier.
The subminiature zero ohm transimpedance sensor input uses a stereo jack to provide both positive and negative phase inputs. Only one input phase is required but having both phases available can accommodate a balanced differential sensor system.A 2.2K* subminiature output jack provides a high impedance output that can be used to drive a local headphone or monitor amplifier. It many situations this jack will eliminate the need to use a separate direct box to get a local output.
A 9-24 volt DC subminiature input jack can provide power to the amplifier if phantom power is not provided to the low impedance TA3M output jack. However, most modern mixers will provide sufficient phantom power.
A subminiature slide switch can mute the signal at the low impedance output jack. The unit can continue to operate on phantom power and provide a signal to the subminiature high impedance output jack while the mute switch is on.
A green LED will indicate power to the amplifier either from phantom power or from the 9-24 volt input.
A Switchcraft miniature TA3M jack provides a parallel pin locking connector for the low impedance output. Rice Audio® manufactures 6 and 12 foot cables to adapt this output to a standard size A3M plug.
The thumb wheel gain adjust operates over a wide range to accommodate different sensor sizes and signal strengths.
A #4-40 blind nut (hidden by the label) and screw provides a convenient mounting system. The screw can be replaced by a longer one to provide a mechanically secure mounting. The device could also be mounted using an adhesive tape.
The small size of the unit ( 1.52 x 2.28 x 0.75 inches ) enables it to be mounted on or close to the instrument sensors. Minimizing the length of cable between the sensors and the pre-amplifier will reduce noise and the possibility of electromagnetic interference.