1. Introduction
Thank you for choosing the Zendstanding HA400 4-Channel Headphone Amplifier. This manual provides essential information for the proper setup, operation, and maintenance of your device. Please read these instructions carefully before use to ensure optimal performance and longevity of the product.
2. Product Overview
The Zendstanding HA400 is an ultra-compact 4-channel stereo headphone amplifier designed to distribute a single audio signal to up to four headphones, each with independent volume control. It is suitable for various applications including studio monitoring, stage performances, home recording, and general audio sharing.
Key Features:
- 4-Channel Independent Control: Each of the four output channels features its own volume control knob, allowing individual users to adjust their listening level without affecting others.
- Low Noise JRC4580 Operational Chip: Incorporates an upgraded JRC4580 operational amplifier chip for high fidelity, low noise, and high gain, ensuring clear audio reproduction.
- 1/4" TRS Connectors: Equipped with a 1/4" TRS input for the signal source and four 1/4" TRS outputs for headphones. Compatible with headphones requiring 32-100 Ω impedance.
- Ultra-Compact Metal Design: Constructed with a durable metal chassis, the device is compact and portable, making it easy to transport and integrate into any setup.
- Multi-Scenario Application: Ideal for studio and stage use, outdoor performances, small concerts, home karaoke, and conference speeches.
3. Package Contents
Please check the package for the following items:
- Zendstanding HA400 Stereo Headphone Amplifier
- 12V DC Power Adapter
- User Manual (this document)
4. Setup Instructions
Follow these steps to set up your HA400 headphone amplifier:
- Connect Power: Plug the included 12V DC power adapter into the "12V ===" input jack on the rear of the HA400. Then, plug the adapter into a standard electrical outlet. The 'ON' indicator light will illuminate when power is supplied.
- Connect Audio Input: Connect your audio source (e.g., mixer, audio interface, computer) to the "INPUT" 1/4" TRS jack on the rear of the HA400 using a 1/4" TRS audio cable.
- Connect Headphones: Ensure the HA400 is powered off or all volume knobs are set to minimum (Level 0) before connecting headphones. Plug your headphones into any of the four 1/4" TRS output jacks (labeled 1, 2, 3, 4) on the front of the unit.
Important Note: To avoid a loud audible thump, always plug in headphones before powering on the amplifier or increasing volume levels.
5. Operating Instructions
Once the HA400 is set up, follow these steps for operation:
- Power On: Ensure all volume knobs are at their minimum setting (Level 0). Connect the power adapter to an electrical outlet. The 'ON' indicator light will illuminate.
- Adjust Input Source Volume: Start playing audio from your connected source at a moderate level.
- Adjust Headphone Volume: Slowly turn the individual 'LEVEL' knob for each connected headphone channel clockwise to increase the volume to a comfortable listening level.
- Power Off: To power off the unit, turn all 'LEVEL' knobs to their minimum setting, then disconnect the power adapter from the electrical outlet.
6. Specifications
| Feature | Specification |
|---|---|
| Model Name | HA400 Headphone Amplifier |
| Channels | 4 Stereo Channels |
| Input Interface | 1 x 1/4 inch TRS Jack |
| Output Interface | 4 x 1/4 inch TRS Jacks |
| Connectivity Technology | Wired |
| Recommended Headphone Impedance | 32-100 Ω |
| Max. Output Level (100Ω) | Approx. 40mA |
| Operational Chip | JRC4580 |
| Power Supply | 12V DC, 1A Adapter (Included) |
| Material | Metal (Composite) |
| Product Dimensions (L x W x H) | 4.08 x 2.25 x 1.83 inches (approx. 105 x 55 x 45 mm) |
| Item Weight | 0.3 Kilograms / 10.7 ounces |
7. Troubleshooting
If you encounter issues with your HA400, please refer to the following common problems and solutions:
- No Sound:
- Ensure the power adapter is securely connected and the 'ON' indicator light is illuminated.
- Verify that the audio input cable is correctly connected to both the HA400's INPUT and your audio source.
- Check that your audio source is playing and its output volume is not muted or set too low.
- Confirm that the individual 'LEVEL' knob for the affected headphone channel is turned up.
- Test with different headphones and audio cables to rule out faulty accessories.
- Distorted Sound:
- Reduce the volume level on your audio source. Overdriving the input can cause distortion.
- Lower the individual 'LEVEL' knob for the affected headphone channel.
- Ensure your headphones' impedance is within the recommended range (32-100 Ω).
- Loud Thump When Plugging In Headphones:
- This is a known characteristic. Always plug in your headphones to the HA400 before powering on the unit or increasing any volume levels to avoid this sound.
8. Maintenance
To ensure the longevity and proper functioning of your HA400:
- Cleaning: Use a soft, dry cloth to clean the exterior of the unit. Do not use liquid cleaners or solvents.
- Storage: Store the device in a cool, dry place away from direct sunlight and extreme temperatures.
- Handling: Avoid dropping the unit or subjecting it to strong impacts.
- Power: Always use the provided 12V DC power adapter. Using an incorrect power supply may damage the unit.
9. Safety Information
Please observe the following safety precautions:
- Do not expose the unit to water or excessive moisture.
- Do not attempt to open or service the unit yourself. Refer all servicing to qualified personnel.
- Avoid listening at excessively high volume levels for prolonged periods, as this can cause hearing damage.
- Keep the unit away from heat sources and open flames.
- Ensure proper ventilation around the unit during operation.
10. Warranty and Support
For warranty information or technical support, please refer to the documentation provided at the time of purchase or contact Zendstanding customer service through their official website or the retailer where the product was purchased.