1. Introduction
The Douk Audio ST-01 Plus is a versatile 2-channel TPA3255 Bluetooth amplifier designed for home audio systems. It features multiple input options including Bluetooth 5.2, RCA, and MM Phono, making it compatible with a wide range of audio devices such as turntables, phones, computers, and TVs. The amplifier delivers a maximum output power of 300W per channel, capable of driving most passive speakers. Unique features include a built-in VU meter, adjustable bass and treble controls, and a 3.5mm AUX output for connecting additional audio equipment.
Image 1.1: Front view of the Douk Audio ST-01 Plus amplifier, showcasing its compact design and prominent VU meter.
2. What's in the Box
- 1x ST-01 PLUS Amplifier
- 1x DC 32V/5A Power Adapter
- 1x Bluetooth Antenna
Image 2.1: Contents of the Douk Audio ST-01 Plus package, including the amplifier, power adapter, and Bluetooth antenna.
3. Product Overview
3.1 Front Panel Controls
Image 3.1: Detailed view of the front panel with labels for each control and indicator.
- VU Meter: Displays audio output level.
- Input Indicators (BT, RCA, Phono): Lights up to show the currently selected input.
- Mode/Volume Knob: Press to switch input modes (BT, RCA, Phono). Rotate to adjust volume.
- Bass Knob: Adjusts low-frequency audio output.
- Treble Knob: Adjusts high-frequency audio output.
- IR Receiver: For remote control signals.
3.2 Rear Panel Connections
Image 3.2: Detailed view of the rear panel with labels for all input and output ports.
- Bluetooth Antenna Port: Connect the included Bluetooth antenna.
- Audio Input (RCA): Connect audio sources via RCA cables.
- Phono Input (MM): Connect turntables with MM cartridges.
- 3.5mm AUX Output: Connect to another amplifier, active speakers, or a subwoofer.
- Speaker Output (Banana Plugs): Connect passive speakers.
- DC 24V-48V Input: Connect the power adapter.
3.3 Internal Components
The ST-01 Plus utilizes high-quality audio components for superior sound performance:
- TPA3255 Amplifier Chip: Delivers up to 300W per channel with low distortion.
- QCC304X Bluetooth Chip: Supports SBC/APTX/APTX-LL/APTX-HD for high-quality, low-latency wireless audio streaming.
Image 3.3: Visual representation of the TPA3255 amplifier chip and QCC304X Bluetooth chip, highlighting key internal components.
4. Setup
4.1 Connecting Speakers
- Ensure the amplifier is powered off.
- Connect your passive speakers to the Speaker Output terminals on the rear panel using banana plugs or bare wire. Ensure correct polarity (red to red, black to black).
4.2 Connecting Audio Sources
Choose one of the following methods to connect your audio source:
- RCA Input: Connect devices like CD players, computers, or TVs using RCA cables to the Audio Input (RCA) ports.
- MM Phono Input: Connect a turntable with an MM cartridge to the Phono Input ports.
- Bluetooth: For wireless connection, ensure the Bluetooth antenna is connected.
Image 4.1: Illustration of various input options including Bluetooth, Phono, RCA, and AUX output, demonstrating the amplifier's compatibility.
4.3 Power Connection
- Connect the DC 32V/5A power adapter to the DC 24V-48V Input port on the rear panel.
- Plug the power adapter into a suitable wall outlet.
5. Operating Instructions
5.1 Power On/Off
Rotate the Mode/Volume knob clockwise until it clicks to power on the amplifier. Rotate counter-clockwise until it clicks to power off.
5.2 Input Selection
Press the Mode/Volume knob to cycle through the available input modes: Bluetooth (BT), RCA, and Phono. The corresponding indicator light on the front panel will illuminate.
5.3 Volume Control
Rotate the Mode/Volume knob to adjust the output volume. Turn clockwise to increase volume and counter-clockwise to decrease.
5.4 Tone Control
Use the Bass and Treble knobs to adjust the low and high frequencies of the audio output according to your preference.
5.5 Bluetooth Pairing
- Select Bluetooth input mode by pressing the Mode/Volume knob until the BT indicator lights up.
- On your device (phone, tablet, etc.), enable Bluetooth and search for "Douk Audio ST-01 Plus".
- Select the amplifier to pair. Once connected, the BT indicator will remain solid.
- To clear Bluetooth pairing records, press and hold the Mode/Volume knob for approximately 3 seconds while in Bluetooth mode.
5.6 VU Meter
The integrated VU meter dynamically displays the audio output level. Its sensitivity can be adjusted to better match different input signals, providing a visual aid for real-time audio adjustment.
Image 5.1: Close-up of the illuminated VU meter, showing the needle responding to audio signals.
5.7 Official Product Videos
Watch these official videos for a visual guide on the Douk Audio ST-01 Plus amplifier's features and operation:
Video 5.1: An overview of the Douk Audio ST-01 200W Bluetooth Amplifier, demonstrating its features and connectivity.
Video 5.2: A demonstration of the Douk Audio ST-01 Tube Power Amp with its VU Meter in action.
6. Specifications
| Feature | Specification |
|---|---|
| Item dimensions L x W x H | 4.53 x 3.84 x 2.13 inches |
| Voltage | 30 Volts (DC) |
| Manufacturer | Douk Audio |
| Maximum Supply Voltage | 48 Volts (DC) |
| Minimum Supply Voltage | 24 Volts (DC) |
| Mounting Type | Surface Mount |
| Brand | Douk Audio |
| Number of Channels | 2 |
| Output Power | 600 Watts (Total, max 300W per channel) |
| Package Type Name | box |
| Specification Met | FCC |
| Supply Current | 5 Amps |
| Material | Metal |
| Product Dimensions | 4.53 x 3.84 x 2.13 inches |
| Item Weight | 2.9 pounds |
| ASIN | B09FPTJ6XD |
| Item model number | ST-01 |
| Date First Available | September 8, 2021 |
7. Troubleshooting
- No Sound:
- Ensure the power adapter is securely connected and the amplifier is powered on.
- Verify that speakers are correctly connected to the output terminals with proper polarity.
- Check that the correct input source is selected (BT, RCA, Phono).
- Confirm the volume is not set to minimum on the amplifier or your audio source.
- If using Bluetooth, ensure the device is paired and connected.
- Bluetooth Connection Issues:
- Ensure the Bluetooth antenna is securely attached.
- Move your Bluetooth device closer to the amplifier to improve signal strength.
- Clear previous Bluetooth pairing records on the amplifier (refer to section 5.5) and your device, then attempt to re-pair.
- Ensure no other devices are actively connected to the amplifier via Bluetooth.
- Distorted Sound:
- Reduce the volume on both the amplifier and your audio source.
- Check speaker connections for loose wires or incorrect polarity.
- Ensure the audio source is not sending an overdriven signal.
8. Maintenance
- Keep the amplifier in a dry, well-ventilated area away from direct sunlight, heat sources, and moisture.
- Clean the exterior with a soft, dry cloth. Avoid using harsh chemicals or abrasive cleaners.
- Ensure proper airflow around the unit to prevent overheating.
9. Warranty and Support
Douk Audio products are designed for reliability and performance. For warranty information, technical support, or service inquiries, please refer to the contact information provided with your purchase or visit the official Douk Audio website. Please retain your proof of purchase for warranty claims.
