The Denon DN-SC3900 is now fully natively supported in MIDI mode in VirtualDJ v7.4 or above.

Please ensure that you have the latest drivers and firmware (v1100 or above) installed on each DN-SC3900: http://www.denondj.com

Connecting your DN-SC3900(s):

Connect each DN-SC3900 directly to your computer's USB ports for the first time in order to install the drivers. Later you can use a powered USB hub if you don't have enough free USB ports on your computer.

While the decks initialize their communication with your computer the words "PC MODE" and "Connecting" should appear on the display. Once the initialization is complete, the words "PC MODE" and "Completed!" will appear on the display. Now your decks are ready!

(Windows only) Before starting VirtualDJ, open the DENON DJ ASIO Control Panel and make sure that you see two devices listed, and that BOTH have a check mark in front of them. Close the DENON DJ ASIO control panel and then start VirtualDJ and continue with the sound configuration below.

(Mac) Creating an aggregate 4 channel sound card for two DN-SC3900's:

NOTE: On Mac, there is a known USB audio problem, which is being worked on.

Because each DN-SC3900 is a separate device with its own 2 channel (1 stereo) sound card, you will need to create an aggregate device in MacOS to combine them into a single 4 channel (2 stereo) multi-channel sound card to use in VirtualDJ's sound configuration.

To do this:

  • Make sure that VirtualDJ is currently closed.

  • Go to MacOS Utilities -> Audio MIDI Setup

  • Go to View menu -> Show Audio Window (If it's not already shown)

  • Click + at the bottom of the devices list to create a new Aggregate Device

  • Double-click on its name (Aggregate Device) and rename it to Denon DN-SC3900

  • Tick both DN-SC3900 devices in the list.

  • Close Audio MIDI Setup and start VirtualDJ.

Sound Configuration (PC):

Go to CONFIG -> Sound Setup and choose the following settings:

Inputs: None
Outputs: External Mixer
Sound card: ASIO -> DENON DJ ASIO Driver

Click APPLY.

Sound Configuration (Mac):

NOTE: On Mac, there is a known USB audio problem, which is being worked on.

Go to CONFIG -> Sound Setup and choose the following settings:

If you have 2 DN-SC3900's using the aggregate sound card device that you created above:

Inputs: None
Outputs: External Mixer
Sound card: 4-out card -> DN-SC3900

Click APPLY.

If you have 1 DN-SC3900 and are not using another external sound card for your output:

Inputs: None
Outputs: Single Output
Sound card: Simple -> DN-SC3900

Click APPLY.

Playing CD's or USB media:

If you switch to CD or USB media mode while VirtualDJ is running this will cut off the sound card and the MIDI driver (It's the equivalent of pulling out the USB cable) and you will get a sound card error in VirtualDJ.

After switched back to PC mode on the DN-SC3900, you will need to go to CONFIG -> Sound Setup and click APPLY to reset the sound. You may also need to rescan for the MIDI device if this doesn't happen automatically. To do this, go to CONFIG -> Mappers, click on the button to the right of the drop-down list and choose the option to rescan for connected devices. Alternatively, you can map a button on your keyboard to the following VDJScript action: rescan_controllers & refresh_controller

If you need to switch seamlessly between VirtualDJ and CD's/USB media, then you should consider purchasing and using a suitable external DJ multi-channel sound card such as Numark DJIO. This will allow you to switch sources on demand without any problems. Otherwise, you should only use CD/USB media as an emergency backup.


  • If you are having audio problems try using a different sound card. Users have had mixed success with the inbuilt sound cards on the SC3900s. It's definitely worth trying another.

  • If your left deck controls the right side of VirtualDJ and vice-versa, simply press the EJECT button on ONE of your decks (not on both) to invert them.

  • Please ensure that you have the latest firmware installed on each Denon DN-SC3900 from http://www.denondj.com - If the units have older firmware installed, they will not work in native MIDI mode.

  • If you have been using a hybrid MIDI mapper prior to v7.4, then you will need to remove it from the Mappers and Devices folders for native MIDI mode to work (Otherwise it will override the native support.)

  • Make sure that each DN-SC3900 is set to the default MIDI channel 1 (Do not change the second player to channel 2 otherwise it will not work with VirtualDJ.)

  • Make sure that Unit Number is set to 1 on each DN-SC3900.

Denon SC3900 - Configuration changes for Hybrid MIDI mode (VirtualDJ v7.0.5b - v7.3 only):

  • NOTE: These changes are not required if you are using the SC3900 in native MIDI mode with VirtualDJ v7.4 or above.

  • Go into the Utility mode and change the Hybrid MIDI Freq. to use is the 2KHz option. Not Scratch Live.

  • Change the Hybrid MIDI LED preset setting to Normal Mode, so that VirtualDJ can control the LED's appropriately. See page 42 onwards of the Denon DN-SC3900 user manual.

    ** These are the ONLY change that should be made on the SC39000. DO NOT change the MIDI Channel assignments. They should both be set to MIDI Ch. 1.

  • Push the MIDI Button and select the Hybrid MIDI mode.

VirtualDJ Configuration for Hybrid MIDI mode (VirtualDJ v7.05b - v7.3 only):

  • NOTE: The DN-SC3900 is now natively supported in MIDI mode in VirtualDJ v7.4 or above. Hybrid mode is no-longer required.

  • Because timecode must be used for Hyrbrid MIDI mode, you will need a suitable sound card for timecode use. On a Windows PC, this also needs to be ASIO capable.

  • Download the Hybrid mapping files. Install these files from the download before opening VirtualDJ.

  • In VirtualDJ, go to CONFIG -> Sound Setup tab and configure it as follows:

    Inputs: Timecodes (Left Ch. 1&2 / Right Ch. 3&4)
    Outputs: External Mixer (Deck 1 - Ch. 1&2 / Deck 2 - Ch. 3&4)
    Sound card: (PC) ASIO -> Choose your timecode sound card in the list
    Sound card: (Mac) 4-out card -> Choose your timecode sound card in the list

  • Click the Timecode Config button to make setting changes for timecode:

    -- Make sure the tab labelled BOTH is selected (default)
    -- From the Timecode drop-down list - chose the LAST option for 2000Hz signal
    -- Leave the mode option on Smart Relative
    -- Adjust the Pan/Anti knob so it is at 12 o'clock (straight up)
    -- Adjust the Gain so it is around 10 o'clock

  • Recommended optional settings:

    -- Click on the Debug button
    ---- Check Disable ClearSound
    ---- Check AntiSkip
    ---- Check Disable Pitch
    ---- Slide the Lead time slider FULL LEFT for 0.0ms lead time.

If you did everything correctly above, then you should be able to press PLAY on the SC3900 decks and see your input signal at this point in the calibration boxes and should have 100% quality signal.

Now you can select OK or Apply on all the open dialog boxes to return to the VirtualDJ interface and start mixing.

Return to Controller Config & Troubleshooting...