1. Introducció
The Gemini SDJ-4000 is a professional dual-deck media player designed for DJs seeking a standalone solution with comprehensive control. This unit features a vibrant 7-inch high-definition screen for intuitive navigation and track management, eliminating the need for an external computer during performances. It integrates a 4-channel mixer, touch-capacitive jog wheels, and 16 multi-color performance pads, offering a versatile platform for creative mixing and live performance. With built-in DSP effects and extensive connectivity options, the SDJ-4000 is suitable for both aspiring and experienced DJs.
2. Què hi ha a la caixa
Please check the contents of your Gemini SDJ-4000 package. If any items are missing or damaged, contact your retailer immediately.
- SDJ-4000 Mixer Unit
- Adaptador d'alimentació
- Cables USB
- Manual d'instruccions (aquest document)
3. Configuració
Follow these steps to set up your Gemini SDJ-4000 for the first time:
- Desembalatge: Carefully remove the SDJ-4000 unit and all accessories from the packaging. Retain the packaging for future transport or storage.
- Connexió d'alimentació: Connect the provided power adaptor to the DC input on the rear panel of the SDJ-4000 and then plug it into a suitable power outlet. Ensure the power switch is in the OFF position before connecting.
- Sortida d'àudio: Connect the MASTER OUTPUT (XLR or RCA) from the SDJ-4000 to your amplifier, powered speakers, or PA system. For balanced connections, use the XLR outputs. For booth monitoring, connect the BOOTH output to your monitor speakers.
- Fonts d'entrada: Connect your external audio sources (e.g., turntables, CD players) to the PHONO/LINE INPUTS on the rear panel. Ensure the input selector switches match your device type (Phono for turntables, Line for CD players/other line-level devices).
- Connexió del micròfon: If using microphones, connect them to the MIC 1 or MIC 2 inputs on the rear panel.
- Mitjans USB: Insert your USB drives containing music files into the USB 1 or USB 2 ports on the top panel.
- Auriculars: Connect your headphones to the headphone jack on the front panel for cueing and monitoring.
- Encès: Once all connections are secure, switch the power button on the rear panel to the ON position. The unit will power up and display the main interface on the 7-inch screen.

Figure 3.1: Rear panel connections of the Gemini SDJ-4000. This image highlights the various input and output ports, including power, USB, MIDI, balanced XLR master outputs, RCA booth output, phono/line inputs for channels 3 and 4, and microphone inputs.
4. Instruccions de funcionament
The Gemini SDJ-4000 offers a comprehensive set of features for dynamic DJ performances. This section details the primary operational aspects.
4.1. Navigating the 7-inch HD Screen
The central 7-inch HD screen provides visual feedback for track selection, waveforms, and settings. Use the browse knob and associated buttons (PLAYLIST, INFO, VIEWS) to navigate your music library, view track details, and switch between vertical and horizontal waveform displays.

Figure 4.1: The 7-inch HD screen showing track details, elapsed time, key, BPM, and dual waveforms for two decks. This allows for visual beat matching and track analysis.
4.2. Jog Wheels and Performance Pads
The touch-capacitive jog wheels offer precise control for scratching, nudging, and searching. Activate 'Vinyl Mode' for authentic scratching. Below each jog wheel are 8 multi-color performance pads that provide access to various creative modes:
- Hot Cues: Instantly jump to predefined points in a track.
- Bucles: Create and trigger seamless loops.
- Tallador: Chop a section of a track into segments for re-arranging.
- roll: Trigger momentary loop rolls.

Figure 4.2: Close-up of the left deck, showing the illuminated jogwheel and the multi-color performance pads. The pads are lit up, indicating active functions like Hot Cues, Loops, Slicer, and Roll.
4.3. Mixer and Effects
The SDJ-4000 features a 4-channel mixer with dedicated gain, 3-band EQ (High, Mid, Low), and filter controls for each channel. It includes both built-in DSP effects and 'Fast FX' for quick sound manipulation.
- Built-in DSP FX: Access effects like Reverb, Delay, Slice, Flanger, Phaser, and Filter to customize your sound.
- Fast FX: Dedicated buttons for Filter, Chop, Noise, and Flanger allow for instant, impactful effects.

Figure 4.3: The central mixer section with individual channel controls for gain, EQ, and volume faders. The 'Fast FX' section is prominently displayed with dedicated buttons for Filter, Chop, Noise, and Flanger.
4.4. Connectivity and Sync
The SDJ-4000 supports standalone operation, MIDI control, and connection to external players. The 'Link' function allows you to connect multiple SDJ-4000 units to share USB libraries and synchronize players. Use 'Master Sync Quantize' to ensure your tracks are always perfectly in time.

Figure 4.4: Two Gemini SDJ-4000 units are shown side-by-side, illustrating the 'Link' feature which enables sharing of USB libraries and synchronized playback between multiple players.
4.5. USB Inputs and Recording
The unit features two USB inputs for playing music directly from USB drives. Additionally, you can record your mix directly to a connected USB drive using the dedicated USB REC function.
4.6. Official Product Video: Features of the SDJ-4000
Vídeo 4.1: Aquest vídeo ofereix una visió generalview of the key features and functionalities of the Gemini SDJ-4000, demonstrating its capabilities in a practical setting. It highlights the screen interface, jog wheels, performance pads, mixer, and effects.
5. Manteniment
Proper maintenance ensures the longevity and optimal performance of your Gemini SDJ-4000.
- Neteja: Regularly wipe the unit with a soft, dry cloth. For stubborn dirt, use a slightly damp cloth and then dry thoroughly. Avoid abrasive cleaners, solvents, or waxes.
- Protecció contra la pols: Keep the unit covered when not in use to prevent dust accumulation, especially on the jog wheels, faders, and screen.
- Ventilació: Assegureu-vos que hi hagi una ventilació adequada al voltant de la unitat per evitar el sobreescalfament. No bloquegeu cap obertura de ventilació.
- Emmagatzematge: Store the unit in a cool, dry place away from direct sunlight and extreme temperatures. If transporting, use appropriate protective casing.
- Gestió de cables: Periodically check all cables for wear and tear. Replace any damaged cables immediately to prevent electrical hazards or signal loss.
6. Solució De Problemes
If you encounter issues with your Gemini SDJ-4000, refer to the following common troubleshooting steps:
- Sense energia:
- Ensure the power cable is securely connected to the unit and the power outlet.
- Verify the power switch on the rear panel is in the ON position.
- Proveu la presa de corrent amb un altre dispositiu per confirmar que funciona.
- Sense sortida de so:
- Check all audio cable connections (Master Output, Booth Output) to your speakers/ampmés viu.
- Ensure the Master Volume and Channel Faders on the SDJ-4000 are turned up.
- Verify that your speakers/amplifier are powered on and their volume is adjusted correctly.
- Check the input source selection for each channel to ensure it matches the connected device (USB, Phono, Line).
- Unitat USB no reconeguda:
- Ensure the USB drive is formatted to a compatible file system (FAT32 or HFS+).
- Try inserting the USB drive into a different USB port on the SDJ-4000.
- Verify that your music files are in a supported format (e.g., MP3, WAV, AAC).
- Some large capacity or specific brand USB drives may not be fully compatible. Try a different USB drive.
- Screen Freezes or Unit Reboots:
- Perform a soft reset by turning the unit off and then on again.
- Ensure the unit has adequate ventilation to prevent overheating.
- Check for the latest firmware updates on the Gemini website and install if available.
- Efectes que no funcionen:
- Ensure the FX ON/OFF button is engaged for the desired effect.
- Adjust the DRY/WET knob to control the intensity of the effect.
- Verify the correct source is selected for the effect.
If the issue persists after trying these steps, please contact Gemini customer support for further assistance.
7. Especificacions
| Característica | Detall |
|---|---|
| Dimensions del producte | 26 x 17.17 x 4.37 polzades (66 x 43.6 x 11.1 cm) |
| Pes de l'article | 20 lliures (9.07 kg) |
| Nom del model | SDJ-4000 |
| Tecnologia de connectivitat | USB |
| Mida de la pantalla | 7 polzades |
| Canals mescladors | 4 canals |
| Coixinets de rendiment | 16 multi-function pads |
| Efectes | Built-in DSP FX (Reverb, Delay, Slice, Flanger, Phaser, Filter), Fast FX (Filter, Chop, Noise, Flanger) |
| Entrades | 2x USB, Phono/Line, 2x Microphone (TRS/XLR combo, 1/4") |
| Sortides | Balanced XLR Master, RCA Master, RCA Booth, Headphone |
| Compatibilitat MIDI | Sí |
| Funció d'enllaç | Yes, for sharing USB libraries and syncing players |
8. Garantia i assistència
The Gemini SDJ-4000 comes with a limited manufacturer's warranty. Please refer to the warranty card included in your product packaging for specific terms and conditions, including coverage duration and claim procedures. For technical support, service, or to inquire about replacement parts, please visit the official Gemini weblloc web o poseu-vos en contacte amb el seu departament d'atenció al client. Conserveu el comprovant de compra per a reclamacions de garantia.
For the latest information, firmware updates, and additional resources, please visit the official Gemini weblloc.





