The following article has been taken directly from the S4's User Manual, If you need any further assistance please consult NI support.
Adding a Microphone
Starting from the basic setup, we add here a microphone and show you how to use it on the Aux channel of TRAKTOR.
Connect Your Microphone to the MIC Socket
The MIC socket and its dedicated GAIN knob.
On the rear panel of your S4, plug your microphone into the Microphone socket (MIC).
Before you connect your microphone, make sure that the GAIN knob next to the MIC socket is turned fully down!
Set the Input Routing in TRAKTOR and Adjust the Microphone Input Level
If you have configured the basic setup via the Setup Wizard, the audio input routing is already set for your microphone and you can skip this section.
Otherwise, set the input routing as follows:
1. Open the Preferences window by clicking on the Preferences button in TRAKTOR’s Header:
2. Go to Preferences > Input Routing > Input Aux and select 3: In: Mic In (mono) and 4: In: Mic In (mono) in the L (Mono) and R menu, respectively:
3. While keeping an eye on the small level meters to the right of the L (Mono) and R menus, sing something in your microphone at the loudness at which you will sing during your per- formance, and adjust the Microphone Gain knob (GAIN) located next to the Microphone socket (MIC) on your S4 until the level meters on your screen show a satisfying level.
4. When the meters show a satisfying level, click Close at the bottom of the Preferences windows to confirm your modifications.
Once the microphone input gain is set, don’t touch this GAIN knob anymore. To control the volume of your microphone within your mix, use the MIC VOL knob on the S4’s front panel in- stead (see below).
Your microphone signal is now sent to the Aux channel in TRAKTOR. This has following interesting consequences:
▪ The volume of the microphone is controlled by the MIC VOL knob on the front panel of your S4:
▪ You can also control the microphone volume via the AUX knob at the right of the crossfader in TRAKTOR:
▪ You can select the microphone signal for use in the Loop Recorder by choosing Aux in the Loop Recorder’s Source menu:
▪ By having assigned the microphone signal to the Aux channel, you still have four internal Decks at your disposal (Track Decks or Remix Decks).