1. Product Overview
The DIY NOW ZK-SUB1200Q is a high-performance digital amplifier board designed for audio enthusiasts. It features dual original TPA3255 chips for powerful output, supports Qualcomm APTX-HD lossless decoding with a 24-bit ES9023 DAC for high-fidelity sound, and includes an NE5532 operational amplifier for low noise. This board offers subwoofer expansion with frequency and volume adjustment, making it compatible with 2.1 channel systems. An optimized heat dissipation design with a brushed heat sink and silent fan ensures stable operation.
The ZK-SUB1200Q amplifier board, featuring a central cooling fan and multiple capacitors, ready for integration into an audio system.
2. Specifications
| Attribute | Value |
|---|---|
| Product Name | Qualcomm APTX Edition BT Amplifier Board with subwoofer extension |
| Product Model | ZK-SUB1200Q |
| Supply Voltage | DC 18-50V (Max 53V, recommended 36-48VDC, 10A or above) |
| Maximum Power Output | Single channel 600W@50V, 2Ω; 300W@50V, 4Ω |
| Bluetooth Encoding Format | SBC/AAC/APTX/APTX-HD |
| Input Method | Bluetooth + AUX |
| Number of Channels | 2.0 + Subwoofer (2.1 channels) |
| Amplifier Chip | Two original TPA3255 chips |
| Decoding Chip | ES9023 (24-bit HyperStream, SNR 112dB) |
| Operational Amplifier | Original TI NE5532 (low noise, high fidelity) |
| Protection Mechanism | Input undervoltage, overheating, overcurrent, short circuit protection. (No input anti-reverse protection; positive and negative poles cannot be reversed!) |
| Product Size (Integrated) | 151 x 120 x 37mm |
| Product Size (Lead Type) | 132 x 120 x 37mm |
| Package | SOP (Standard Operating Procedure) |
Diagram showing the dimensions of the integrated board (151x120x37mm) and the lead type board (132x120x37mm).
3. Setup Instructions
3.1 Unpacking
Carefully remove the amplifier board and accessories from the packaging. Verify all components are present:
- 1x ZK-SUB1200Q Amplifier Board
- 1x Accessory Kit (may include potentiometer leads, knobs, etc., depending on the version)
Two packaging options: one for integrated potentiometers and another for lead-type potentiometers, showing components neatly packed.
3.2 Component Identification and Connections
Refer to the diagram below for identifying connection points and controls:
Detailed diagram illustrating power input (DC 18-50V), left/right speaker connections, LINE IN (3.5mm), expansion ports, subwoofer output, and control knobs for master volume, bass adjustment, bass frequency, and treble.
- Power Input (DC 18-50V): Connect a DC power supply (5.5-2.5DC female socket or 2P terminal block). Ensure the voltage is within 18-50VDC, with a maximum limit of 53V. A 36-48VDC, 10A or above power supply is recommended. WARNING: No input anti-reverse protection; positive and negative poles cannot be reversed!
- Speaker Connections: Connect your left and right channel speakers to the designated terminals.
- LINE IN Input: Use a 3.5mm audio cable to connect an external audio source.
- Subwoofer Signal Output Expansion Interface: Connect to a subwoofer or a pure post amplifier board for 2.1 channel setup.
- Expansion Port 1: Connects to the audio input of a MIC front stage board or a pure rear stage amplifier input port.
- Expansion Port 2: Connects to a MIC front stage board reverb output or Qualcomm decoding board audio output.
- Joint Defense POP Control Interface: Used for cascading with other boards to prevent pop sounds during power on/off.
3.3 Optional Installations
3.3.1 External Antenna Installation (Special Scenario)
The board is equipped with onboard antennas, providing a normal Bluetooth distance of 10-15 meters. If the board is installed in a metal enclosure (which may block the signal) or if you require an increased Bluetooth distance (20-30 meters), an external 2.4G antenna is necessary. You will need to purchase a 2.4G antenna, including an antenna extension cable and antenna rod. The IPEX/IPX generation antenna base is already soldered onto the amplifier board.
Guide for installing an external 2.4G antenna for improved Bluetooth range, showing the IPEX/IPX generation antenna base already soldered onto the board.
3.3.2 ZK-AMP Microphone Front-End Board Installation
To integrate a microphone, connect the ZK-AMP microphone front-end board as shown in the diagram. Ensure the dial switch on the ZK-SUB1200Q is turned to the OFF position when using the expansion interface.
Wiring diagram for connecting the ZK-AMP microphone front-end board, including power supply (18-50VDC for main board, 8-26VDC for mic board) and expansion port connections. Notes to turn dial switch to OFF position.
3.3.3 Subwoofer Expansion with Joint Defense POP Control
For subwoofer expansion, connect the ZK-SUB1200Q to a pure post amplifier board (e.g., ZK-6002) as illustrated. The cascading anti-POP control interface ensures that even when the cascading power is turned off, there will be no audible pop sound.
Illustration of connecting the SUB1200Q with a ZK-6002 pure post amplifier board for subwoofer expansion, highlighting the joint defense POP control interface to prevent pop sound.
4. Operating Instructions
4.1 Power On/Off
Rotate the master volume knob clockwise to turn on the amplifier. Rotate it counter-clockwise to the end to turn off the amplifier.
4.2 Bluetooth Pairing
- Ensure the amplifier board is powered on.
- On your mobile device, open Bluetooth settings and search for available devices.
- Select "Wuzhi Audio" (or similar name) from the list to pair. The device supports aptX HD for high-quality audio streaming.
- For external button control, refer to the wiring diagram for PLAY/PAUSE, PREV/VOL-, and NEXT/VOL+ functions. A long press (3s) on PLAY/PAUSE will disconnect Bluetooth.
A video demonstrating the physical connections, power-up sequence, Bluetooth pairing process, and audio performance of the ZK-SUB1200Q amplifier board with connected speakers and subwoofer.
4.3 Audio Adjustments
- Master Volume: Controls the overall output volume.
- Bass Adjustment: Adjusts the intensity of low frequencies.
- Bass Signal Frequency Adjustment: Fine-tunes the subwoofer crossover frequency (20-200Hz).
- Treble Adjustment: Adjusts the intensity of high frequencies.
5. Maintenance
- Cleaning: Use a soft, dry cloth to clean the board. Avoid using liquids or abrasive cleaners.
- Ventilation: Ensure the cooling fan and heat sinks are free from dust and obstructions to maintain optimal heat dissipation. Regularly check for dust buildup and clean gently with compressed air if necessary.
- Storage: Store the amplifier board in a dry, cool environment away from direct sunlight and extreme temperatures.
6. Troubleshooting
- No Power: Check the power supply connection and ensure the voltage is within the specified range (DC 18-50V). Verify the master volume knob is turned on.
- No Sound Output: Double-check all speaker and audio input connections. Ensure Bluetooth is correctly paired or the AUX cable is securely connected.
- Distorted Sound: Reduce the input volume from your audio source or the master volume on the amplifier. Check speaker impedance compatibility.
- Bluetooth Connection Issues: Ensure the amplifier is within range of your device. Disconnect and re-pair the Bluetooth connection. If using an external antenna, ensure it is properly installed.
- Pop Sound on Power On/Off: If using subwoofer expansion with a cascading setup, ensure the joint defense POP control interface is correctly utilized to prevent pop sounds.
- Overheating: Ensure the cooling fan is operating and not obstructed. Verify proper ventilation around the amplifier board.
7. User Tips
- For optimal performance and longevity, use a stable DC power supply within the recommended voltage range (36-48VDC) and with sufficient current (10A or above).
- Consider installing an external 2.4G antenna if the amplifier board is enclosed in metal or if you require extended Bluetooth range.
- Always double-check wiring, especially power polarity, as the board lacks anti-reverse protection.
- Experiment with the bass signal frequency adjustment to find the best blend between your main speakers and subwoofer for your listening environment.
8. Safety and Compliance Information
⚠ WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
9. Warranty and Support
For any questions, technical support, or warranty inquiries, please contact the seller, Electronics Kit Store, directly through the platform where the product was purchased. Please provide your order details and a clear description of the issue for prompt assistance.