1. Introduction
The MAOZUA BT-309A and BT-298A are versatile 2-channel HIFI audio amplifiers designed for both home and car entertainment systems. Featuring Bluetooth connectivity, USB/SD card playback, FM radio, and microphone inputs for karaoke, these amplifiers offer a comprehensive audio solution. They are equipped with intuitive controls for volume, bass, treble, and microphone adjustments, ensuring a personalized listening experience.
2. Key Features
- Bluetooth Connectivity: Seamlessly connect smartphones, tablets, and other Bluetooth-enabled devices (Bluetooth Version 5.0 for BT-309A).
- Multiple Audio Inputs: Supports USB disk, SD/MMC card for MP3 playback, and AUX input.
- FM Stereo Radio: Built-in FM tuner for listening to your favorite radio stations.
- Karaoke Function: Two microphone inputs with independent volume and echo control for an immersive karaoke experience.
- Tone Control: Adjustable Bass and Treble controls to fine-tune your audio output.
- Digital Display: LCD display with backlight for clear indication of broadcast channel and operational status.
- Remote Control: Full-function infrared remote control for convenient operation.
- Dual Power Supply: Compatible with both AC 220V (home) and DC 12V (car) power sources.
- Durable Construction: Made from high-quality iron material for longevity.
3. Package Contents
Please check the box for the following items:
- 1 x MAOZUA BT-309A or BT-298A Power Amplifier
- 1 x Remote Control
- 1 x User Manual
4. Specifications
| Feature | BT-309A | BT-298A |
|---|---|---|
| Model Number | BT-309A | BT-298A |
| Bluetooth Version | 5.0 | Wireless Bluetooth |
| Input Voltage | AC 220V / DC 12V | AC 220V-240V 50/60HZ / DC 12V |
| Impedance | 4-16Ω | 4-16Ω |
| Rated Power | 50W + 50W | 80W + 80W |
| Max Power | 400W + 400W | 300W + 300W |
| Frequency Response | 10-20kHz | 20Hz - 20kHz (±3dB) |
| FM Frequency | 87.5 - 108 mHz | N/A |
| Distortion Rate | 0.04% | ≤ 0.5% |
| Signal-to-Noise Ratio | >88dB | ≥ 90dB |
| Sound Channel | 2.0 Channel | 2.0 Channel |
| Sensitivity | 0.25 mV - 220 mV | Signal Input: 200MV(±30MV) MIC Input: 9MV(±2MV) |
| Output Levels | N/A | Recording: ≈1V Auxiliary: ≈1V |
| Supported Media | SD-Card, U Disk, MP3 Format Play, FM Stereo Radio, Bluetooth | USB, MP3 Format Play, Bluetooth |
| Dimensions (L x W x H) | 20cm x 19cm x 5.5cm (Approx.) | Approx. 18cm x 13.8cm x 5.5cm (7'' x 5.4'' x 2'') |
| Material | Iron | Iron |
| Certification | CE | CE |
5. Controls and Interfaces
5.1 Front Panel Overview
- Power Switch: Turns the amplifier ON/OFF.
- USB/SD LED Display: Shows current mode, track number, or FM frequency.
- Mode Button: Switches between input sources (Bluetooth, USB, SD, FM, AUX).
- Play/Pause Button: Starts or pauses playback.
- Previous/Next Buttons: Navigates tracks or FM stations.
- Bass Adjustment: Adjusts low-frequency audio levels.
- Treble Adjustment: Adjusts high-frequency audio levels.
- MIC VOL (Microphone Volume): Adjusts the volume of connected microphones.
- ECHO: Adjusts the echo effect for microphones.
- MUSIC VOL (Master Volume): Adjusts the overall output volume.
- MIC1/MIC2 Input: 6.35mm jacks for connecting microphones.
- USB Port: For connecting USB flash drives.
- SD/MMC Card Slot: For inserting SD or MMC memory cards.
5.2 Rear Panel Overview
- AUDIO INPUT (AUX IN): RCA jacks for connecting external audio sources (e.g., CD player, TV).
- SPEAKER OUTPUT (L/R): Terminals for connecting passive speakers (4-16Ω impedance).
- POWER DC INPUT (12V): For connecting a 12V DC power supply (e.g., car battery).
- AC POWER INPUT (220V-240V): For connecting to a standard AC power outlet.
- FM ANT: Terminal for connecting the FM radio antenna.
5.3 Remote Control
The remote control allows you to manage various functions from a distance, including power, mode selection, track navigation, volume adjustment, and EQ settings.
6. Setup Instructions
Follow these steps to set up your amplifier:
- Connect Speakers: Connect your passive speakers to the SPEAKER OUTPUT terminals on the rear panel. Ensure correct polarity (positive to positive, negative to negative) for each channel (Left and Right). The amplifier supports speakers with an impedance of 4-16Ω.
- Connect Audio Source (Optional):
- AUX Input: Use an RCA cable to connect external audio devices (e.g., CD player, DVD player, TV) to the AUDIO INPUT (AUX IN) jacks.
- USB/SD Card: Insert a USB flash drive into the USB port or an SD/MMC card into the card slot on the front panel.
- Microphones: Plug microphones into the MIC1 or MIC2 input jacks on the front panel.
Connecting USB, SD Card, and Microphones. - Connect FM Antenna (Optional): If you plan to use the FM radio, connect the included FM antenna to the FM ANT terminal on the rear panel. Extend the antenna for better reception.
- Power Connection:
- For Home Use (AC 220V-240V): Connect the AC power cord to the AC POWER INPUT on the rear panel and then to a wall outlet.
- For Car Use (DC 12V): Connect a 12V DC power supply (e.g., car battery) to the POWER DC INPUT terminals on the rear panel. Ensure correct polarity.
- Power On: Flip the POWER switch on the front panel to the 'ON' position. The LCD display should light up.
7. Operating Instructions
7.1 Basic Operation
- Select Input Mode: Press the 'MODE' button on the front panel or remote control to cycle through available input sources: Bluetooth, USB, SD, FM, AUX. The selected mode will be shown on the LCD display.
- Adjust Volume: Use the 'MUSIC VOL' knob on the front panel or the volume buttons on the remote control to adjust the master volume.
- Adjust Tone: Use the 'BASS' and 'TREBLE' knobs to adjust the low and high frequencies to your preference.
7.2 Bluetooth Mode
- Switch the amplifier to Bluetooth mode using the 'MODE' button. The display will show 'BT' or similar.
- On your mobile device, enable Bluetooth and search for available devices.
- Select 'BT-309A' or 'BT-298A' (or similar name) from the list to pair. A confirmation sound may play.
- Once paired, you can play audio from your device through the amplifier.
7.3 USB/SD Card Playback
- Insert a USB flash drive or SD/MMC card containing MP3 audio files into the respective slot.
- Switch the amplifier to USB or SD mode using the 'MODE' button. Playback should start automatically.
- Use the 'PREV/NEXT' buttons to skip tracks and 'PLAY/PAUSE' to control playback.
7.4 FM Radio Mode
- Switch the amplifier to FM mode using the 'MODE' button. The display will show the FM frequency.
- Press the 'AUTO' button (or similar on remote) to automatically scan and save available radio stations.
- Use the 'PREV/NEXT' buttons to navigate through saved stations.
7.5 Microphone & Karaoke Function
- Connect one or two microphones to the MIC1/MIC2 input jacks.
- Adjust the 'MIC VOL' knob to control the microphone volume.
- Adjust the 'ECHO' knob to add an echo effect to your vocals.
8. Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the amplifier. Do not use liquid cleaners or aerosols, as they may damage the finish or internal components.
- Ventilation: Ensure the amplifier has adequate ventilation. Do not block the ventilation openings on the unit.
- Storage: When not in use for extended periods, store the amplifier in a cool, dry place away from direct sunlight and extreme temperatures.
- Power Off: Always turn off the amplifier and disconnect it from the power source before cleaning or performing any maintenance.
9. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No power | Power cord not connected; Power switch off; No power from outlet/battery. | Check power connections; Ensure switch is ON; Test outlet/battery. |
| No sound output | Incorrect input mode; Volume too low; Speakers not connected or faulty; Audio source issue. | Select correct input mode; Increase master volume; Check speaker wiring; Verify audio source is playing. |
| Bluetooth not connecting | Amplifier not in Bluetooth mode; Device not in pairing mode; Interference. | Switch to Bluetooth mode; Ensure device Bluetooth is ON and searching; Move closer to amplifier; Restart both devices. |
| USB/SD card not playing | Incorrect mode; Unsupported file format; Corrupted files; Card/drive not inserted correctly. | Switch to USB/SD mode; Ensure files are MP3 format; Reinsert card/drive; Try a different card/drive. |
| Microphone not working | Microphone not plugged in; MIC VOL too low; Microphone faulty. | Ensure microphone is fully plugged in; Increase MIC VOL; Test with another microphone. |
| Poor FM reception | Antenna not connected or extended; Weak signal. | Connect and extend FM antenna; Reposition antenna for better signal. |
10. User Tips
- For optimal sound quality, ensure your speakers are rated within the amplifier's impedance range (4-16Ω).
- When using the amplifier in a car, always ensure the 12V DC power connection is secure and correctly polarized to prevent damage.
- Experiment with the Bass and Treble controls to find the sound profile that best suits your music and listening environment.
- To avoid feedback when using microphones, try to keep the microphones away from the speakers and adjust the MIC VOL and ECHO settings carefully.
- If experiencing Bluetooth connection issues, try unpairing and re-pairing the device, or restarting both the amplifier and your Bluetooth device.
11. Warranty and Support
This product is covered by a standard manufacturer's warranty against defects in materials and workmanship. Please refer to your purchase documentation for specific warranty terms and duration.
For technical support or service inquiries, please contact the retailer or manufacturer directly. Keep your proof of purchase handy when seeking support.
