Beta Three RaI5 User Manual page 6

Ra15
APPLICATION SAMPLE
3.Stereo+Mic(one)
In this situation two speakers can play signal in MIC and stereo together
4.Stereo+Mic(two)
In this situation two speakers can play signal in MIC and stereo together
Signal Source
Press this button to choose the MIC
Signal Source
Press this button to choose the MIC
4