1. Introduction
This manual provides detailed instructions for the setup, operation, and maintenance of your XY-ST21PRO 2.1 Channel Bluetooth Digital Amplifier Board. Please read this manual thoroughly before use to ensure proper functionality and to prevent damage.
2. Safety Information
- Ensure the power supply voltage is within the specified range (DC12-30V) and provides sufficient current (5A or above). Incorrect power can damage the device.
- Avoid exposing the amplifier board to moisture, water, or extreme temperatures.
- Do not attempt to disassemble or modify the board beyond the instructions provided. Unauthorized modifications may void the warranty and pose safety risks.
- Keep out of reach of children.
- Ensure proper ventilation to prevent overheating, especially when operating at high power.
3. Package Contents
Depending on the purchased set, your package may include:
- Set 1: Amplifier board x 1
- Set 2: ST21 amplifier board x 1, Shell kit x 1
- Set 3: Amplifier board x 1, Lead wire x 5
Note: Power supply and audio cables are not included and must be purchased separately.
4. Product Features
- High-Performance Design: Utilizes high-power digital amplifier dedicated inductors, ensuring high current, low magnetic loss, and minimal heat generation. Features a magnetic shielding mechanism to resist electromagnetic interference.
- Dual-Core Stability: Equipped with two TPA3221 chips, supporting 2.1-channel Bluetooth digital amplification with 100W+100W+200W high power for enhanced stability.
- Superior Sound Quality: Constructed with lossless components for better sound quality and independent tuning of high and low frequencies.
- Bluetooth Connectivity: Supports Bluetooth 5.2 with a welded IPEX interface. Allows for connection to an external Bluetooth antenna for extended range or when enclosed in a metal casing.
- Multiple Audio Inputs: Supports Bluetooth, AUX input, USB flash drive playback, and acts as a sound card.
- Robust Protection Mechanisms: Includes protection against input undervoltage, input anti-reverse connection, overheating, overcurrent, and short circuit.
Figure 1: Internal Components and Quality Materials
Figure 2: Dual Core Design for Reliability (TPA3221 Chip and High Power Inductor)
5. Setup Instructions
Follow these steps to set up your XY-ST21PRO amplifier board:
5.1 Component Identification and Wiring
Figure 3: Accurate Wiring and Function Guide
Figure 4: Rear Panel Connections
5.2 Connections
- Power Supply: Connect a DC12-30V/5A or above power supply to the DC seat (5.5-2.5mm) labeled 'DC12-30V power supply'. Ensure correct polarity.
- Speaker Connections: Connect your right and left channel speakers to the terminals labeled 'Speaker connection (right channel)' and 'Speaker connection (left channel)'. Connect your subwoofer to the 'Subwoofer' terminals.
- Audio Input:
- AUX Input: Connect an audio source (e.g., smartphone, MP3 player) to the 'AUX import' jack.
- USB Input: Insert a USB flash drive into the 'U disk/sound card input' port for direct music playback.
- Bluetooth: Ensure no other audio input is active when using Bluetooth.
- External Bluetooth Antenna (Optional): If installing the board in a metal casing or desiring extended Bluetooth range (20-30 meters), connect a 2.4G external antenna to the welded IPEX interface. (Refer to Figure 5: BT Antenna Interface).
Figure 5: BT Antenna Interface
5.3 Initial Power-Up
After all connections are secure, switch the 'Power' toggle to the ON position. The BT playback indicator will light up, indicating the board is powered on and ready for use.
Video 1: Demonstrates wiring, powering on, Bluetooth pairing, and adjusting audio controls.
6. Operating Instructions
6.1 Power Control
- Use the 'Power' toggle switch to turn the amplifier board ON or OFF.
6.2 Audio Input Selection
The amplifier supports multiple audio input modes: Bluetooth, AUX, and USB flash drive. The system automatically detects the active input. Ensure only one input source is active at a time for optimal performance.
6.3 Bluetooth Pairing
- Turn on the amplifier board. The BT playback indicator will flash, indicating it's in pairing mode.
- On your mobile device, enable Bluetooth and search for available devices.
- Select 'XinYi' (or the customized BT name) from the list to pair. A confirmation sound will indicate successful pairing.
Figure 6: Bluetooth Connection Tips
6.4 USB Flash Drive Playback
- Insert a USB flash drive containing WAV, FLAC, APE, or MP3 audio files into the 'U disk/sound card input' port.
- The USB flash drive play indicator will light up.
- Use the control knob (refer to Figure 3) for playback functions:
- Click: Pause/Play
- Double Click: Next track
- Three Strikes and One Hit: (Function not explicitly defined, typically mode switch or repeat)
- Four Hits Mode Switch: (Function not explicitly defined, typically input mode switch)
- Press and Hold: (Function not explicitly defined, typically power off or reset)
Figure 7: USB Flash Drive Music List and EQ User-Defined
6.5 Tone and Volume Adjustment
Use the dedicated potentiometers (knobs) on the board to adjust audio output:
- Subwoofer Volume: Adjusts the output level of the subwoofer.
- Subwoofer Frequency: Controls the crossover frequency for the subwoofer.
- Left and Right Channel Bass Adjustment: Adjusts the bass level for the main stereo channels.
- Left and Right Channel Treble Adjustment: Adjusts the treble level for the main stereo channels.
- Left and Right Channel Volume Adjustment: Controls the overall volume for the main stereo channels.
6.6 Sinilink APP Control
The amplifier board can be controlled via the Sinilink APP. This allows you to change the Bluetooth name and set a pairing password.
- Download and install the Sinilink APP on your mobile device.
- Connect to the amplifier board via Bluetooth as described in section 6.3.
- Open the Sinilink APP. You can change the BT name and set a password. Click the "Set" button within the app to apply changes.
Figure 8: Sinilink APP Interface for Customization
7. Specifications
| Parameter | Value |
|---|---|
| Product Name | BT Audio Amplifier Board |
| Product Model | XY-ST21 PRO |
| Power Supply | DC12-30V / 5A or above |
| DC Seat | 5.5-2.5mm |
| Bluetooth Version | 5.2 |
| Audio Input | Bluetooth + AUX + USB Flash Drive + Sound Card |
| Bluetooth Audio Decoding | AAC SBC |
| USB Audio Support | WAV FLAC APE MP3 |
| Dimensions (Without Casing) | Approx. 111 x 100 x 23mm (4.37 x 3.94 x 0.91 inches) |
| Dimensions (With Shell) | Approx. 112 x 102 x 28mm (4.41 x 4.02 x 1.10 inches) |
| Potentiometer Wire Length | Approx. 20cm |
| Weight | 0.260kg |
Output Power (Left & Right Channel)
| Power | Conditions |
|---|---|
| 10W + 10W | @ 8Ω / 12VDC |
| 20W + 20W | @ 4Ω / 12VDC |
| 35W + 35W | @ 8Ω / 24VDC |
| 70W + 70W | @ 4Ω / 24VDC |
| 60W + 60W | @ 8Ω / 30VDC |
| 100W + 100W | @ 4Ω / 30VDC |
Output Power (Subwoofer)
| Power | Conditions |
|---|---|
| 10W | @ 8Ω / 12VDC |
| 20W | @ 4Ω / 12VDC |
| 35W | @ 8Ω / 24VDC |
| 70W | @ 4Ω / 24VDC |
| 60W | @ 8Ω / 30VDC |
| 100W | @ 4Ω / 30VDC |
| 200W | @ 2Ω / 30VDC |
Figure 9: Product Dimensions for Different Versions
8. Maintenance
- Cleaning: Use a soft, dry cloth to clean the surface of the amplifier board. Do not use liquid cleaners or solvents.
- Storage: Store the device in a cool, dry place away from direct sunlight and excessive dust.
- Handling: Handle the board with care to avoid damaging electronic components.
9. Troubleshooting
- No Power: Check the power supply connection and ensure the power switch is ON. Verify the power adapter is functioning correctly and provides the specified voltage and current.
- No Sound:
- Ensure speakers are correctly connected and functional.
- Check the audio input source (Bluetooth, AUX, USB) is properly selected and playing.
- Verify volume levels on both the amplifier board and the audio source are not set to minimum.
- If using Bluetooth, ensure successful pairing.
- Poor Sound Quality:
- Check all wiring for loose connections or damage.
- Ensure the power supply meets the minimum current requirements.
- Adjust bass, treble, and subwoofer frequency controls to optimize sound.
- If using Bluetooth, ensure your device is within range and there is no significant interference.
- Bluetooth Connection Issues:
- Ensure the amplifier is in pairing mode (BT indicator flashing).
- Forget the device on your phone's Bluetooth settings and try pairing again.
- If the board is in a metal enclosure, consider installing an external Bluetooth antenna.
- Overheating: Ensure the amplifier board has adequate ventilation. Reduce volume or power output if overheating persists. The built-in protection mechanism should prevent damage from excessive heat.
10. User Tips
- Power Supply: Always use a power supply that matches the recommended voltage (DC12-30V) and provides at least 5A current for stable performance, especially when driving higher power speakers.
- Speaker Matching: Pay attention to the impedance ratings of your speakers (e.g., 4Ω, 8Ω) and match them with the amplifier's output capabilities for optimal sound and to prevent damage.
- External Antenna: If you enclose the amplifier board in a metal case, an external Bluetooth antenna is highly recommended to maintain a strong and stable wireless connection.
- App Control: Utilize the Sinilink APP for convenient customization of Bluetooth name and password, enhancing your user experience.
11. Warranty and Support
For warranty information, technical support, or service inquiries, please contact your retailer or the manufacturer directly. Keep your purchase receipt as proof of purchase.
