Native Instruments Traktor Kontrol S4 Mk2
The Kontrol S4 MK2 is a 4 deck all-in-one controller with a sturdy build quality and integrated sound card. The MK2 has substantial improvements over the S4 MK1, including large multicolor buttons. The MK1 is not supported and cannot be supported because it uses a proprietary communication protocol exclusive to Traktor. The MK2 uses the standard HID protocol (also used by keyboards & mice) to send and receive signals from a computer, so it can work with Mixxx. The easiest way to tell the MK1 apart from the MK2 is the appearance of the jog wheel. On the MK1, the top of the jog wheel is black plastic; on the MK2, the top of the jog wheel is shiny aluminum.
The mapping for the Kontrol S4 Mk2 is included in Mixxx 2.0, although it is incomplete.
The Kontrol S4 Mk2 can run from USB bus power. Using the separate power supply increases the brightness of the LEDs, which is helpful for using it in daylight, and increases the volume of the headphone output.
The Kontrol S4 MK2 is a USB class compliant audio, HID, and MIDI device, so it is compatible with Mixxx without any proprietary drivers on GNU/Linux and Mac OS X. However, with Mixxx 2.0 on GNU/Linux, an additional udev rule file needs to be installed for the HID device to be detected by Mixxx. On Windows, it is recommended to install the driver from Native Instruments and select the ASIO sound API in the Sound Hardware section of Mixxx's Preferences.
With the S4 plugged in, a MIDI device is listed as an available controller in Mixxx's Preferences. That is the MIDI input/output ports on the back of the S4 for connecting external MIDI gear; no mapping for the S4 will appear in the menu for the MIDI device. The controller uses HID for the knobs, buttons, and other components on the device, so the mapping can only be loaded when you select the HID device on the left side of Mixxx's Preferences.
The phono inputs on the S4 can be used with turntables for timecode vinyl control of Mixxx. Unlike Traktor, there is no additional software to install to use timecode with the S4; the free version of Mixxx is the full version. However, note that Mixxx is not compatible with Traktor Scratch Mk2 timecode; refer to the Mixxx manual for a list of supported types of timecode.
Most of the functions are mapped as they appear on the device and most users coming from Traktor should not have a problem picking up and using the controller right away. While there is a lot of overlap between Mixxx and Traktor, some buttons on the S4 do not quite translate to Mixxx. This guide is not a replacement for the Mixxx Manual and any questions not answered here ("What is keylock?") are addressed there.
Note that Mixxx doesn't have the concept of a single "master" deck for sync. Instead, you should push and hold the sync button to "lock" sync on for all decks you want to remain in sync. Or you can push Shift + Sync to lock sync on. See the Mixxx manual for details.
Mixxx does not have remix decks, so the four remix slot buttons have been repurposed. By default, they will launch samples in the sampler decks.
The Loop Size select knob is not fully implemented. Currently, pressing the "Loop Set" knob always creates an 8 bar loop, and turning the knob will change the size of existing loops. This will be fixed in a future update to allow creation of arbitrary-sized loops.
The FX Mode button changes which effect is loaded in the FX bank. Currently only one effect can be loaded in each bank.
There are some more bonus actions that can be accessed by holding shift and pressing certain buttons.
- Shift + Loop Move will adjust the musical pitch of the track without changing the speed.
- Shift + pressing the Loop Move knob will reset the musical pitch to natural.
- Shift + Loop Size will seek quickly through the track for easy previewing.
- Shift + Load will eject the track.
- Shift + Remix Slot will create a loop of predetermined size.
The Master Volume knob on the S4 controls the built-in hardware volume directly, so we have chosen not to also bind it to the Mixxx software master volume control. Peak display is only generated from software, however. So if you see or hear clipping, it won't help to lower the master volume knob -- adjust the knob in the Mixxx GUI or lower the gain of the playing tracks.
- Snap button does nothing (in Mixxx, Quantize does both Quantizing and Snapping)
- Master button does nothing, but lights up when sync is enabled
- Loop recorder knob and buttons do nothing
- FX knob buttons do nothing
- While the Flux button works, the Reset button does nothing
If you choose, you can edit the controller script and change the Remix Slot buttons to perform loop rolls instead. Also by default, Shift + CUE rewinds the track to the beginning but you can change this to a Reverse Roll (or "Censor") effect instead.
Making these changes is still a little awkward and we will be making controller preferences easier to change in the future. For now you'll have to make a small change to the mapping script file. Don't worry, the actual edit only involves replacing a single word in a text file.
- Open Mixxx Preferences and select the Kontrol S4 in the side list.
- You should see a series of tabs at the top of the preferences window, one of which is "Scripts". Select that tab.
- Select "Traktor-Kontrol-S4-MK2-hid-scripts.js".
- Click "Open Selected File."
- Either the file should open in an editor, or you should see a file browser window with that file selected. If you see a file browser, right click the file and select an option to edit it.
- At the top of the file will be short instructions explaining what to do.
There are some features we still plan to add to this mapping:
- New effects interface in Mixxx 2.1
- Loop size readout / selection
- On Air indicator for shoutcast or set recording
- Find uses for other unused buttons
- Microphone volume knob
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Mixxx is a free and open-source DJ software.
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