BOSS 644UA Mobile Audio System User Manual

Introduction

This manual provides comprehensive instructions for the BOSS 644UA Mobile Audio System, a CD/MP3/WMA player with AM/FM radio, USB, SD card, and auxiliary input capabilities.

Key Features

• PLL Synthesizer Stereo Radio
• CD/MP3/WMA Player
• Automatic Memory Storing
• Full Detachable Panel
• Preset Equalization
• Electronic Shockproof (ESP) Function
• Memory Card Interface
• USB Interface
• Auxiliary Input Function
• Remote Control

Installation

General Notes

• Choose a mounting location that does not interfere with driving.
• Temporarily connect wiring to ensure proper function before final installation.
• Use only supplied parts; unauthorized parts may cause malfunctions.
• Consult a dealer for any drilling or vehicle modifications.
• Install the unit to avoid obstructing the driver or injuring passengers during sudden stops.
• Avoid installing where the unit is subject to high temperatures, direct sunlight, hot air, dust, dirt, or excessive vibration.
• Installation angle should not exceed 30 degrees from horizontal for optimal performance.

Mounting Methods

DIN FRONT-MOUNT (Method A)

This method is for installing the unit into a standard dashboard opening.

Before Installation

• Remove the two screws securing the unit before installation. (Diagram: Illustrates removing two screws from the front of the unit before installation.)

Installation Opening

The unit fits into any dashboard with a suitable opening. (Diagram: Shows a typical car dashboard opening designed for a DIN-sized audio unit.)

Installing the Unit

Follow these steps after testing all connections:

1. Ensure the ignition is off and disconnect the vehicle battery's negative terminal.
2. Disconnect the wire harness and antenna.
3. Press the release button on the front panel and remove the control panel. (Diagrams: Illustrate pressing the release button to detach the front panel.)
4. Lift and pull out the outer trim ring.
5. Insert the supplied keys into the slots on the sides of the unit's sleeve and slide the sleeve off the back of the unit. (Diagram: Shows keys inserted into slots and the sleeve being removed.)
6. Mount the sleeve into the dashboard opening, bending the tabs to secure it. (Diagram: Shows the metal sleeve being inserted into the dashboard opening, with tabs bent to secure it in place.)
7. Reconnect the wire harness and antenna, ensuring no wires are pinched.
8. Slide the unit into the sleeve until it locks.
9. Secure the unit with the supplied metal strap, attaching one end to the unit's mounting bolt and the other to a solid metal part of the vehicle for grounding. (Diagram: Illustrates the metal securing strap being attached to the back of the unit and to a solid part of the vehicle's dashboard for grounding.)
10. Reconnect the battery's negative terminal. Replace the outer trim ring and install the front panel.

Removing the Unit

1. Turn off the ignition and disconnect the battery's negative terminal.
2. Remove the metal strap.
3. Press the release button to remove the front panel.
4. Lift and pull out the outer trim ring.
5. Insert the keys into the unit's side slots and pull the unit out of the dashboard. (Diagram: Shows the process of inserting keys into the unit's side slots and pulling the unit out of the dashboard sleeve.)

DIN REAR-MOUNT (Method B)

This method is suitable for vehicles like Nissan and Toyota, using factory radio mounting brackets.

• Use the screw holes marked 'T' (Toyota) or 'N' (Nissan) on the sides of the unit.
• Align the unit's screw holes with the vehicle's factory radio mounting brackets and tighten 5x5mm screws on each side. (Diagram: Shows the side view of the unit with screw holes marked 'T' and 'N', indicating how they align with factory radio mounting brackets in a vehicle's dashboard or console.)
• Note: The outer trim ring, sleeve, and metal strap are not used for Method B.

Using the Detachable Front Panel

Removing the Front Panel

1. Press the release button on the front panel and pull it off. (Diagrams: Show the release button on the front panel and the panel being detached.)
2. Store the front panel in its protective case. (Diagram: Shows the front panel stored in its protective case.)

Installing the Front Panel

Insert the front panel into the housing and ensure it is properly installed. Incorrect installation may affect display or key functions. (Diagram: Shows the front panel being inserted back into the main unit's housing.)

Precautions when Handling

• Do not drop the front panel.
• Avoid applying pressure to the display or controls during removal/installation.
• Do not touch the contacts on the front panel or main unit body.
• Clean contacts with a dry cloth if dirty.
• Do not expose the front panel to high temperatures or direct sunlight.
• Keep volatile agents away from the front panel surface.
• Do not attempt to disassemble the front panel.

Wiring Connection

Diagram Description: A block diagram illustrates the wiring for the 60x4W system. It shows the MAIN UNIT connected to a RADIO ANTENNA, LINE OUT JACKS, and a FUSE (5A). Connections are detailed for a 4-SPEAKER SYSTEM (Rear Left, Front Left, Front Right, Rear Right) using color-coded wires (GREEN/BLACK, GREEN, WHITE/BLACK, WHITE, GRAY/BLACK, GRAY, VIOLET/BLACK, VIOLET). Additional connections include Ground Wire (Black), +12V Accessory/Switch (Red), Power Antenna/Amplifier Turn On (Blue), and +12V Constant Power Supply (Yellow).

Operation

Location of Keys

The following lists the numbered keys on the main unit and remote control:

• Main Unit: 1. Release button, 2. Tune/Seek/Track Up, 3. Volume knob (rotate for volume, press for SEL), 4. Disc slot, 5. PAU button, 6. SCN button, 7. Preset buttons (1-6), 8. RPT button, 9. MON button, 10. AS/PS/Navi-SCH button, 11. MOD button, 12. Eject button, 13. Liquid crystal display, 14. BND/LOU/ENT button, 15. Tune/Seek/Track Down, 16. SHF button, 17. Memory card interface, 18. DIR- button, 19. DIR+ button, 20. EQ button, 21. USB interface, 22. DISP button, 23. PWR/MUT button, 24. Auxiliary input jack, 25. Reset button, 26. Remote sensor. (Diagrams: One diagram shows the front panel of the main unit with numbered keys. Another diagram shows the remote control with numbered keys.)
• Remote Control: Refer to page 15 for detailed numbering and functions.

Basic Operation

Switching On/Off the Unit

Press the PWR/MUT button (23) to turn the unit on. Press and hold the PWR/MUT button (23) to turn it off.

Faceplate Release

Press the release button (1) to detach the removable front panel.

Sound Adjustment

Press the volume button (3) briefly to cycle through adjustment modes: Volume, Bass, Treble, Balance, Fader. Rotate the volume knob (3) to adjust the selected parameter.

System Setting

Press and hold the volume button (3) to enter system setting mode. Briefly press the volume button (3) to select an item and rotate the volume knob (3) to change the setting.

• BEEP ON/OFF: Use the volume knob (3) to enable or disable beep sound.
• AREA: In radio mode, use the volume knob (3) to select the desired frequency spacing (e.g., OIR/EUR/USA/ASI/S-R/JPN).
• DIM: Rotate the volume knob (3) to adjust backlight brightness (High, Low, Mid).

Loudness

Press and hold the BND/LOU/ENT button (14) for several seconds to reinforce bass output. Press again to disable.

Set the Clock

Press the DISP button (22) until the clock appears. Press and hold DISP (22) until the clock flashes. Use the Tune/Seek Down button (2) for minutes and Tune/Seek Up button (15) for hours.

Display Information

Press the DISP button (22) to cycle through display modes, showing information like clock, ID3 TAG (song title, artist, etc. for MP3/WMA), and other functions.

Equalization

Press the EQ button (20) to access equalization settings. Select from modes like FLAT, CLASSICS, POP, ROCK, or DSP OFF.

Mute

Press the PWR/MUT button (23) briefly to mute the sound. Press again to unmute.

Liquid Crystal Display

The display (13) shows current frequency and activated functions.

Remote Sensor

Point the remote control at the remote sensor (26) on the unit to operate it.

ESP Function

The unit offers electronic shockproof protection for approximately ten seconds.

Auxiliary Input

Connect a portable audio player to the auxiliary input jack (24). Press the MOD button (11) to switch to AUX IN mode.

Reset Function

Use a ballpoint pen or thin metal object to press the reset button (25) for reasons like initial installation issues, non-responsive buttons, or display errors. Note: If the unit does not work after reset, clean the front panel socket with a cotton swab soaked in isopropyl alcohol.

Radio Operation

Switching to Radio Mode

Press the MOD button (11) to select radio mode. The display will show the memory band and frequency.

Selecting the Frequency Band

In radio mode, press the BND/LOU/ENT button (14) to cycle through bands: FM1, FM2, FM3, AM1, AM2.

Selecting Station

Press the Tune/Seek Down button (2) or Tune/Seek Up button (15) for automatic seek tuning. Press and hold for several seconds until "MANUAL" appears for manual tuning. The unit returns to seek tuning automatically if no button is pressed for a period.

Automatic Memory Storing & Program Scanning

• Automatic Memory Storing: Press and hold the AS/PS button (10) for several seconds. The unit scans frequencies and stores the 6 strongest stations into the preset buttons.
• Program Scanning: Briefly press the AS/PS button (10) to scan preset stations. The unit stops at stations with sufficient signal strength.

Station Storing

Select a station using preset buttons (7) (1-6). Press and hold the desired preset button for several seconds to store the current station.

Mono/Stereo

Press the MON button (9) to switch between mono and stereo modes. Mono mode may improve reception for distant stations.

CD/MP3/WMA Operation

Switching to CD Mode

If no disc is inserted, gently insert a CD with the printed side up. The unit will draw it in and start playback. If a disc is already inserted, press the MOD button (11) until CD mode appears.

Selecting Tracks

Press the Tune/Seek Down button (15) or Tune/Seek Up button (2) to move to the previous or next track. Hold these buttons for fast reverse or fast forward.

Pausing Playing

Press the PAU button (5) to pause playback. Press it again to resume.

Previewing Tracks

Press the SCN button (6) to play the first few seconds of each track. Press again to stop preview and listen to the current track. For MP3/WMA discs, holding SCN (6) previews tracks in the current directory.

Repeating Tracks

Press the RPT button (8) to repeat the current track. Press again to stop repeat. Holding RPT (8) repeats all tracks in the current directory for MP3/WMA discs.

Playing Tracks in Random

Press the SHF button (16) to play all tracks on a CD in random order. Press again to cancel. Holding SHF (16) plays all tracks in the current directory in random order for MP3/WMA discs.

Ejecting a Disc

Press the Eject button (12) to stop playback and eject the disc.

Special Functions for MP3/WMA Disc

1) Selecting Directory Up/Down

Use the DIR- button (18) or DIR+ button (19) to navigate directories. This function is only active if the disc contains directories.

2) Selecting Tracks by AS/PS /Navi-SCH Button

The AS/PS (Navi-SCH) button (10) acts as a Digital Audio Mode selector for MP3/WMA. Pressing it cycles through search modes:

• Searching Track Directly: Press AS/PS (10) once. Select track using the volume knob (3) and press volume knob (3) or BND/LOU/ENT button (14) to play.
• Searching Directory or File Name: Press AS/PS (10) twice. Use the volume knob (3) to input characters (A-Z, 0-9, etc.) and confirm with the volume button (3). Press BND/LOU/ENT (14) to start the search.
• Searching From Root Directory: Press AS/PS (10) three times. Navigate from the root directory using the volume knob (3) and BND/LOU/ENT button (14) to select and play songs.
• Searching From Current Directory: Press AS/PS (10) four times. Navigate within the current directory using the volume knob (3). Select and play files by pressing BND/LOU/ENT button (14) or volume knob (3).

USB Play Operation

Connect a USB driver to the USB interface (21). The unit will automatically search and play MP3/WMA files. Alternatively, press the MOD button (11) to select USB mode.

Notes:

• The unit supports standard USB-memory discs.
• Compatibility with MP3 players may vary by brand and model.
• If connecting an MP3 player with a non-rechargeable battery, remove the battery before connecting to prevent potential issues.
• Do not remove the USB driver during playback.

Memory Card Operation

Insert a memory card into the interface (17). The unit will search and play MP3 files automatically. Press the MOD button (11) to select memory card play mode.

Caution

Do not connect USB devices or memory cards containing important files to the unit for playback. Similarly, avoid playing CD-R/RW discs with important files, as incorrect operations could lead to file loss. The company is not responsible for such data loss.

Disc Notes

Notes on Discs

• Use only round CD discs. Non-standard shapes may damage the unit.
• Do not apply paper or tape to disc surfaces, as it may cause malfunctions.
• Dirt, dust, scratches, or warped discs can lead to misoperation.

Notes on CD-Rs/CD-RWs

• The unit cannot play unfinalized CD-R or CD-RW discs. Refer to your CD recorder's manual for finalization procedures.
• Playback of some CD-Rs/CD-RWs may not be supported depending on recording status, disc conditions, or equipment used.
• For reliable playback, use CD-RWs written at 1x-4x speed and recorded at 1x-2x speed. Use CD-Rs written at 1x-8x speed and recorded at 1x-2x speed. Do not use CD-RWs written more than 5 times.

Notes on MP3 Files

• Discs must be in ISO9660 level 1 or level 2 format, or Joliet or Romeo expansion format.
• Ensure MP3 files have the ".MP3" extension. Files with incorrect extensions, even if named as MP3, will not be recognized.

Remote Control

The remote control provides access to all unit functions. Refer to the diagram on page 15 for button identification.

• VOL+: Volume Up / Character Select
• MUTE: Power ON/OFF/MUTE
• SELECT: Sound Mode Select / Character Shift
• TUNE/SKIP (Down): Tune/Seek Down
• DISP: Display Button
• VOL-: Volume Down / Character Select
• PAU: Pause Button
• 1-6: Preset Buttons
• SHF: Shuffle Button
• AS/PS/D-AUD: Auto Memory Store/Program Scan / Mode Select
• MODE: Mode Button
• TUNE/SKIP (Up): Tune/Seek Up
• BAND/LOU/ENT: Band Select (short press) / Loudness (long press) / Enter
• SCN: Scanning Button
• RPT: Repeat Button
• DIR Up: Directory Up Button
• DIR Down: Directory Down Button

Specification

General

• Power Supply Requirements: DC 12 Volts, Negative Ground
• Chassis Dimensions: 178 (W) x 160 (D) x 50 (H) mm
• Tone Controls: Bass (at 100 Hz) ±10 dB, Treble (at 10 kHz) ±10 dB
• Maximum Output Power: 60x4 watts
• Current Drain: 5 Ampere (max.)

CD Player

• Signal to Noise Ratio: More than 55 dB
• Channel Separation: More than 50 dB
• Frequency Response: 40Hz - 18 kHz

Radio

FM Band

• Frequency Coverage: 87.5 to 107.9 MHz
• IF: 10.7 MHz
• Sensitivity (S/N=30dB): 10 dBu
• Stereo Separation: >25dB

AM Band

• Frequency Coverage: 530 to 1710 KHz
• IF: 450 kHz
• Sensitivity (S/N=20dB): 36 dBu

Trouble Shooting

Check wiring connections first. If problems persist, consult your nearest service dealer.