ViewSonic VS13647 User Manual page 26

About the microphone input
If you wish to use a microphone, connect a 3.5 mini jack cable microphone to the
projector.
You can use a wireless microphone as long as a wireless module is attached to
the projector's microphone input jack and it works well with the associated
devices. To ensure a quality use of the wireless microphone, it is recommended
that your microphone conforms to the specifications listed in the table below.
Signal Parameter
Microphone Transducer Principle
Impedance
Frequency response
ViewSonic Pro8400
Min Type
300
600
Max
Dynamic
1K ohm
16K Hz
22