1. Introduction
The ADASTRA 952.982UK AD-400 is a versatile 1U rack-mountable audio player designed for professional audio installations. This unit integrates a slot-feed CD player, USB and SD card inputs, and an FM tuner, offering multiple audio source options. It is supplied with an infrared (IR) remote control and an IR extension cable for flexible operation. This manual provides essential information for the safe and efficient installation, operation, and maintenance of your AD-400 unit.
Key Features:
- Slot-feed CD player
- USB and SD card inputs for digital media playback
- Integrated FM tuner with 30 preset channels
- Backlit LCD display
- Random and repeat playback modes
- Infrared remote control and 1m IR extension cable included
- RCA (L+R) and Optical digital audio outputs
- 1U 19-inch rack mountable design
2. Safety Information
Please read this manual thoroughly before operating the unit. Damage caused by misuse is not covered by the warranty.
- Ensure the correct power supply voltage (100-240Vac, 50/60Hz) is used.
- Do not expose the unit to rain or moisture.
- Avoid placing the unit near heat sources or in direct sunlight.
- Do not open the casing; refer all servicing to qualified personnel.
- Clean the unit with a soft, dry cloth. Do not use water or chemical solvents.
- Ensure adequate ventilation around the unit.
- Disconnect from mains power before cleaning or servicing.
3. Setup
3.1 Unpacking
Carefully unpack the AD-400 unit and check the contents to ensure all items are present and in good condition. The package should include:
- ADASTRA 952.982UK AD-400 Player
- IR Remote Control
- 1m IR Extension Cable
- IEC Mains Power Lead
- FM Antenna
3.2 Rack Mounting
The AD-400 is designed for standard 19-inch rack mounting and occupies 1U of rack space. Secure the unit using appropriate rack screws (not supplied) through the mounting ears on the front panel. Ensure sufficient ventilation space above and below the unit.
3.3 Connections
Before connecting the unit to power, ensure all audio and antenna connections are made.

Image 1: Rear panel of the ADASTRA AD-400 showing power input, audio outputs, IR control, and FM antenna connection.
- Power Connection: Connect the supplied IEC mains power lead to the IEC inlet on the rear panel and then to a suitable mains power outlet (100-240Vac, 50/60Hz).
- Audio Output:
- RCA Output: Connect the L+R RCA outputs on the rear panel to the input of your amplifier or mixer using appropriate RCA cables.
- Optical Output: For digital audio connection, use an optical cable to connect the OPTICAL output to a compatible digital input on your audio system.
- FM Antenna: Connect the supplied FM antenna to the F-type connector labeled "ANTENNA" on the rear panel for optimal FM radio reception.
- IR Extension: If the unit is installed in a location where the remote control's line of sight is obstructed, connect the 1m IR extension cable to the "IR IN" jack on the rear panel. Position the IR receiver end of the cable in a suitable location for remote control operation.
4. Operating Instructions
The AD-400 can be operated using the front panel controls or the supplied IR remote control.
4.1 Front Panel Controls

Image 2: Front panel of the ADASTRA AD-400, showing the slot-feed CD tray, USB/SD slots, LCD display, and control buttons.
- POWER Button: Toggles the unit on/off. The power indicator LED will illuminate when the unit is on.
- CD/USB/SD Button: Selects the input source between CD, USB, and SD card.
- LCD Display: Shows track information, playback status, and FM frequency.
- Slot-feed CD Tray: Insert CDs here.
- USB Port: Insert USB flash drives for media playback.
- SD Card Slot: Insert SD cards for media playback.
- PLAY/PAUSE (►/−): Starts or pauses playback.
- STOP (■): Stops playback.
- SKIP (⏮︎ / ⏭︎): Skips to the previous or next track/file.
- FOLDER (▲ / ▼): Navigates through folders on USB/SD media.
- RANDOM: Toggles random playback mode.
- REPEAT: Toggles repeat playback mode (repeat one, repeat all, repeat folder).
- SEEK (⏪︎ / ⏩︎): Fast forwards or rewinds within a track (CD/USB/SD) or scans for FM stations.
- FM: Activates the FM tuner mode.
- Numeric Buttons (1-0): Direct track selection for CD/USB/SD or direct preset selection for FM.
4.2 Remote Control

Image 3: The remote control for the ADASTRA AD-400, featuring buttons for source selection, playback control, numeric input, and FM functions.
The remote control provides full functionality for the AD-400. Ensure the remote has fresh batteries and a clear line of sight to the unit's IR receiver, or to the IR extension cable's receiver.
- Power Button: Turns the unit on or off.
- CD/USB/SD/FM Buttons: Directly select the desired audio source.
- Numeric Buttons (0-9, 0/10): For direct track selection or FM preset recall.
- PRESET: Cycles through FM presets.
- Navigation Buttons (Up/Down/Left/Right/Enter): Used for menu navigation (if applicable) and folder browsing.
- Playback Controls: Play/Pause, Stop, Skip Forward/Backward, Fast Forward/Rewind.
- RANDOM/REPEAT: Activate random or repeat playback modes.
4.3 CD Playback
- Press the POWER button to turn on the unit.
- Press the CD/USB/SD button until "CD" is selected on the display.
- Gently insert a CD into the slot-feed tray with the label side facing up. The unit will automatically load the CD and begin playback.
- Use the PLAY/PAUSE, STOP, and SKIP buttons to control playback.
- Use the numeric buttons for direct track selection.
4.4 USB/SD Playback
- Press the POWER button to turn on the unit.
- Insert a USB flash drive into the USB port or an SD card into the SD card slot.
- Press the CD/USB/SD button until "USB" or "SD" is selected on the display. The unit will scan the media and begin playback.
- Use the FOLDER buttons to navigate through directories on the USB/SD media.
- Use the PLAY/PAUSE, STOP, and SKIP buttons to control playback.
- Use the numeric buttons for direct track selection.
4.5 FM Tuner Operation
- Ensure the FM antenna is properly connected.
- Press the FM button to switch to FM tuner mode.
- The display will show the current FM frequency.
- Auto Scan: Press and hold the SEEK buttons (⏪︎ / ⏩︎) to automatically scan for available stations. The tuner will stop at the next strong signal.
- Manual Tuning: Briefly press the SEEK buttons to fine-tune the frequency step-by-step.
- Saving Presets: To save a station, press the PRESET button on the remote, use the navigation buttons to select a preset number, and press ENTER (or a similar button) to confirm.
- Recalling Presets: Use the numeric buttons on the remote or the PRESET button to cycle through saved stations.
5. Maintenance
Regular maintenance ensures the longevity and optimal performance of your AD-400 player.
- Cleaning: Use a soft, dry, lint-free cloth to clean the exterior of the unit. Do not use abrasive cleaners, waxes, or solvents.
- CD Tray: Keep the CD slot free from dust and debris. Avoid inserting damaged or dirty CDs.
- Ventilation: Ensure the ventilation openings are not blocked to prevent overheating.
- Storage: If storing the unit for an extended period, disconnect it from power and store it in a cool, dry place.
6. Troubleshooting
If you encounter issues with your AD-400, refer to the following troubleshooting guide.
| Problem | Possible Cause | Solution |
|---|---|---|
| No power | Power cable disconnected; Power switch off; Blown fuse | Check power cable connection; Ensure power switch is ON; Check and replace fuse (F1AL 250V) if necessary (by qualified personnel). |
| No sound output | Incorrect source selected; Audio cables disconnected/faulty; Amplifier/mixer issues | Select correct source (CD/USB/SD/FM); Check RCA/Optical cable connections; Verify amplifier/mixer settings. |
| CD not playing | CD inserted incorrectly; Dirty/scratched CD; Incorrect source selected | Re-insert CD label side up; Clean or try a different CD; Select CD source. |
| USB/SD not recognized | Incompatible format; Corrupted media; Incorrect source selected | Ensure media is formatted correctly (FAT32 recommended); Try different USB/SD media; Select USB/SD source. |
| Poor FM reception | Antenna not connected; Weak signal; Interference | Connect FM antenna; Reposition antenna for better reception; Check for nearby electronic interference. |
| Remote control not working | Dead batteries; Obstruction; IR extension cable not connected/faulty | Replace batteries; Ensure clear line of sight to IR receiver; Check IR extension cable connection. |
7. Specifications
Technical specifications for the ADASTRA 952.982UK AD-400 player.
| Parameter | Value |
|---|---|
| Power Supply | 100-240Vac, 50/60Hz (IEC) |
| Power Consumption | 15 W |
| Fuse | F1AL 250V |
| Frequency Response (CD) | 20Hz - 20kHz |
| Frequency Response (USB/SD/FM) | 40Hz - 16kHz |
| THD (CD) | 0.03% |
| THD (USB/SD) | 0.05% |
| THD (FM) | 0.1% |
| SNR (CD/USB/SD) | 75 dB |
| SNR (FM) | 60 dB |
| FM Frequency Range | 87.5 - 108 MHz |
| FM Channels | 30 memorizable channels |
| Output Connections | L+R RCA, Optical |
| Antenna Connection | F-type connector |
| Dimensions (W x H x D) | 482 x 44 x 175 mm (1U rack mount) |
| Weight | 2.12 kg |
| Material | Metal |





