1. Ynlieding
The Daakro ZK-502L is a high-fidelity 2.0 channel Bluetooth amplifier board designed for DIY audio projects. It delivers 50W + 50W output power, features dual audio input modes (Bluetooth 5.0 and AUX), and operates within a wide DC 9-24V voltage range. This manual provides detailed instructions for the proper setup, operation, and maintenance of your amplifier board.
2. Produktfunksjes
- Dual HiFi Chip: Utilizes two HiFi amplifier chips with PurePath technology for ultra-high resolution, low distortion, and high-fidelity sound.
- 2.0 Channel Output: Supports left and right channel configuration, providing 50W output power per channel for an immersive sound experience.
- Dual Audio Input Modes: Seamlessly switch between Bluetooth 5.0 for wireless connectivity and traditional AUX input for wired audio sources.
- Wide Voltage Berik: Compatible with DC 9-24V power supplies, allowing flexibility with 9V, 12V, 19V, or 24V sources.
- Sprekkerkompatibiliteit: Suitable for 20-200W, 4-8Ω speakers, ensuring broad compatibility with various speaker sizes.
- Wiidweidige beskerming: Built-in mechanisms include over-voltage, ûnder-voltage, over-temperature, short-circuit, and reverse connection protection for device safety.
- Volume kontrôle: Integrated volume knob for easy adjustment of audio output.
3. Package Ynhâld
Kontrolearje oft alle hjirûnder neamde items yn jo pakket oanwêzich binne:
- ZK-502L Amplifier Board
- Top and Bottom Acrylic Plates
- Mounting Hardware (Screws, Spacers, Nuts)
- Volume Knob Cap
- DC Power Kabel
- Kleine Schroevendraaier

4. Component Identification
Familiarize yourself with the various components and connection points on the amplifier board:

- Stromynfier (DC 9-24V): Connect your DC power supply here.
- Left Channel Output (-L +): Connect the left speaker here.
- Right Channel Output (-R +): Connect the right speaker here.
- Volume kontrôle: Rotary knob to adjust the audio output level.
- Bluetooth-yndikator: LED light indicating Bluetooth status.
- AUX-ynfier: 3.5mm-jack foar bedrade audioferbining.
5. Technyske spesifikaasjes
| Spesifikaasje | Wearde |
|---|---|
| Model Number | ZK-502L |
| Channels | 2.0 (Stereo) |
| Output Power | 50W + 50W |
| Ynfier Voltage | DC 9-24V |
| Audio yngongen | Bluetooth 5.0, AUX (3.5mm) |
| Speaker Impedance | 4-8Ω |
| Ofmjittings (L x B x H) | 4.33 x 2.76 x 1.97 inch (sawat) |
| Gewicht | 2.39 ounces (sawat) |
6. Power Output Guidelines
The actual output power varies depending on the input voltage and speaker impedance. Refer to the table below for typical power output values:
| Ynfier Voltage | Speaker Impedance | Output Power (@1KHz) |
|---|---|---|
| 12V | 4Ω | 20W+20W |
| 12V | 8Ω | 12W+12W |
| 15V | 4Ω | 30W+30W |
| 15V | 8Ω | 18W+18W |
| 19V | 4Ω | 40W+40W |
| 19V | 8Ω | 30W+30W |
| 24V | 4Ω | 50W+50W |
| 24V | 8Ω | 40W+40W |
Tink derom: Optimal audio output requires sufficient audio input combined with appropriate power supply voltage and current. A higher voltage and current generally result in higher power output. For the same conditions, a smaller speaker impedance will yield greater power.

7. Setup Ynstruksjes
Follow these steps to set up your Daakro ZK-502L amplifier board:
- Gearstalle de Casing (Optional): If your board came with acrylic plates, use the provided screws and spacers to assemble the protective casing around the amplifier board.
- Sprekkers ferbine: Connect your passive speakers to the Left Channel Output (-L +) and Right Channel Output (-R +) terminals. Ensure correct polarity (+ to + and - to -).
- Ferbine Power Supply: Connect a DC 9-24V power adapter (not included) to the Power Input jack. Ensure the power supply meets the voltage and current requirements for your desired output.
- Ynstellings foar earste folume: Turn the volume control knob counter-clockwise to its minimum position before powering on.

8. Bedriuwsinstruksjes
The ZK-502L amplifier board supports two audio input modes:
8.1. Bluetooth-modus
- Power On: Fersekerje de amplifier board is powered on. The Bluetooth indicator LED will blink, indicating it is in pairing mode.
- Pairing: On your audio source device (e.g., smartphone, tablet, PC), enable Bluetooth and search for available devices. Select "ZK-502L" from the list.
- Ferbining befêstiging: Once successfully paired, the Bluetooth indicator LED will stop blinking and remain solid.
- Spylje audio: Start playing audio on your connected device. Adjust the volume using the amplifier board's volume knob and your source device's volume controls.

8.2. AUX-ynfiermodus
- AUX-kabel ferbine: Insert a 3.5mm audio cable (not included) into the AUX Input jack on the amplifier board. Connect the other end to your audio source device's headphone or audio output jack.
- Automatysk skeakeljen: De amplifier board will automatically switch to AUX input mode when a cable is detected.
- Spylje audio: Start playing audio on your connected device. Adjust the volume using the amplifier board's volume knob and your source device's volume controls.

9. Feiligens foarsoarchsmaatregels
- Soargje derfoar dat de macht oanbod voltage is within the DC 9-24V range. Using an incorrect voltage kin beskeadigje it apparaat.
- Do not short-circuit the speaker outputs or power input.
- Avoid exposing the board to moisture, extreme temperatures, or direct sunlight.
- Handle the board with care to prevent damage to components.
- Skeakelje de stroom út foardat jo ferbiningen of ôfslutingen meitsje.
- Do not attempt to modify the circuit board, as this will void the warranty and may cause damage.
10. Probleemoplossing
- Gjin lûd:
- Check if the power supply is connected correctly and providing the correct voltage.
- Verify speaker connections for correct polarity and secure contact.
- Ensure the volume knob is turned up on both the amplifier board and the audio source device.
- If using Bluetooth, ensure the device is paired and connected. If using AUX, ensure the cable is fully inserted.
- Ferfoarme lûd:
- Ferleegje it folume op beide amplifer en it boarneapparaat.
- Ensure the power supply can provide sufficient current for the desired output power.
- Kontrolearje de kompatibiliteit fan sprekkerimpedânsje (4-8Ω).
- Bluetooth ûntsluting:
- Ensure the audio source device is within the 16.4 feet (5 meters) Bluetooth range.
- Foarkom obstakels dy't it Bluetooth-sinjaal kinne hinderje.
- Besykje it apparaat te ûntkoppelen en opnij te koppelen.
- Stroomindikator net oan:
- Check the power supply connection and ensure it is functioning.
- Verify that the power input terminals are correctly wired.
11. Garânsje en stipe
Daakro provides the following support for your ZK-502L amplifier board:
- 30 dagen garânsje: Your product is covered by a 30-day warranty from the date of purchase.
- 24 Hours Online Customer Service: For any inquiries or technical assistance, please contact Daakro customer support.
- 100% Customer Satisfaction: Daakro is committed to ensuring your satisfaction with their products.
For further assistance, please visit the official Daakro store or contact their customer service team.