OPPO Digital HA-2 Portable Headphone Amplifier User Manual

1. Introduction

The OPPO Digital HA-2 is a high-performance portable headphone amplifier and USB Digital-to-Analog Converter (DAC) designed to enhance the audio quality from your mobile devices and computers. Building on the acclaimed HA-1 desktop amplifier, the HA-2 delivers exceptional sound in a sleek, portable form factor. It supports high-resolution audio formats, providing a rich and detailed listening experience for audiophiles on the go.

2. Safety Information

• Do not expose the device to extreme temperatures, humidity, or direct sunlight.
• Avoid dropping or subjecting the device to strong impacts.
• Do not attempt to disassemble or modify the device. This will void the warranty and may cause damage.
• Use only the provided or approved charging cables and adapters.
• Keep the device away from water and other liquids. If it comes into contact with liquid, power off immediately and do not attempt to use it until it is completely dry and inspected by a professional.
• Prolonged listening at high volume levels can cause permanent hearing damage. Adjust the volume to a comfortable level.

3. Package Contents

Please check that all items are present in the package:

• OPPO Digital HA-2 Portable Headphone Amplifier
• USB Charging Cable
• USB Data Cable (for connecting to source devices)
• 3.5mm Audio Cable
• User Manual (this document)
• Silicone Bands (for stacking with mobile devices)

4. Product Overview

The HA-2 features a sleek design with a genuine leather casing and aluminum frame. It incorporates a high-quality DAC chip and powerful amplification circuitry to deliver pristine audio.

Figure 4.1: Side View of HA-2 with Controls. This image shows the side profile of the OPPO HA-2, highlighting its elegant black leather finish and silver aluminum frame. Visible controls include the volume knob/power switch at the top, LED indicators for battery and input status, and switches for Bass+ and Gain (L/H) settings. The device's compact and premium build is evident.

Figure 4.2: Top View of HA-2 with Hi-Res Audio Logo. This image provides a top-down perspective of the OPPO HA-2, showcasing its slim form factor and the "Hi-Res Audio" certification logo prominently displayed in the upper left corner. The device's minimalist design and the quality of its leather finish are clearly visible, emphasizing its premium audio capabilities.

Controls and Indicators:

• Volume Knob / Power Switch: Located at the top, this knob controls the audio output volume and also serves as the power on/off switch. Turn clockwise to power on and increase volume, counter-clockwise to decrease volume and power off.
• Input Selector: A switch to select between different audio inputs (USB, Line In).
• Bass+ Switch: Engages a bass boost feature for enhanced low-frequency response.
• Gain Switch (L/H): Adjusts the amplifier's gain level. Use 'L' (Low) for sensitive headphones/earphones and 'H' (High) for less sensitive or high-impedance headphones.
• Battery Indicator LEDs: A series of small LEDs that show the current battery charge level.
• USB Input Ports: Dedicated ports for connecting to various source devices (e.g., USB-A for Apple devices, Micro-USB for Android/PC).
• Line In / Line Out Jack: A 3.5mm jack that functions as an analog audio input or a fixed-level line output.
• Headphone Output Jack: A 3.5mm jack for connecting your headphones.

5. Setup

5.1 Charging the HA-2

1. Connect the provided USB charging cable to the HA-2's charging port (usually a Micro-USB port).
2. Connect the other end of the USB cable to a USB power adapter (not always included, but standard phone chargers work) or a computer's USB port.
3. The battery indicator LEDs will illuminate to show charging progress. A full charge typically takes approximately 1.5 hours with a compatible fast charger.

5.2 Connecting to Audio Sources

The HA-2 supports various audio input methods:

• USB DAC Mode (for smartphones/computers):
  • For Apple iOS devices: Use the provided USB-A to Lightning cable (or Apple's Camera Connection Kit).
  • For Android devices: Use the provided Micro-USB to Micro-USB or USB-C to Micro-USB cable (depending on your phone's port). Ensure your Android device supports USB OTG (On-The-Go) audio output.
  • For Computers (Windows/macOS): Connect via the Micro-USB port using a standard USB A to Micro-USB cable. Install necessary drivers for Windows (available on OPPO's official website) if prompted. macOS typically does not require drivers.
• Analog Line-In Mode:
  • Connect an analog audio source (e.g., a portable music player's headphone out) to the HA-2's 3.5mm Line In/Out jack using the provided 3.5mm audio cable.

5.3 Connecting Headphones

Plug your headphones or earphones into the 3.5mm Headphone Output Jack on the HA-2.

6. Operating Instructions

6.1 Powering On/Off

To power on the HA-2, rotate the volume knob clockwise until you hear a click and the indicator LEDs light up. To power off, rotate the volume knob counter-clockwise until it clicks off.

6.2 Volume Control

Adjust the audio output volume by rotating the volume knob. Turn clockwise to increase volume and counter-clockwise to decrease volume. Start with a low volume and gradually increase it to a comfortable listening level.

6.3 Input Selection

Use the Input Selector switch to choose your desired audio source:

• USB: For digital audio input from smartphones, tablets, or computers.
• Line In: For analog audio input from other audio devices.

6.4 Bass+ Feature

Toggle the Bass+ switch to enable or disable the bass boost. This feature enhances the low-frequency response, providing a more impactful bass. Experiment to find your preferred sound.

6.5 Gain Setting (L/H)

The Gain switch allows you to match the HA-2's output level to your headphones' sensitivity:

• L (Low Gain): Recommended for highly sensitive headphones or earphones to prevent excessive volume and potential noise.
• H (High Gain): Suitable for less sensitive or high-impedance headphones that require more power to drive effectively.

If you experience distortion or excessive volume at low settings, switch to Low Gain. If the volume is too low even at maximum, switch to High Gain.

7. Maintenance

• Cleaning: Use a soft, dry cloth to clean the exterior of the device. Do not use abrasive cleaners, solvents, or strong chemicals.
• Storage: When not in use for extended periods, store the HA-2 in a cool, dry place, away from direct sunlight and extreme temperatures.
• Battery Care: To prolong battery life, avoid fully discharging the battery frequently. Charge the device regularly, even if not in constant use.

8. Troubleshooting

9. Specifications

10. Warranty and Support

For warranty information and technical support, please refer to the warranty card included in your product package or visit the official OPPO Digital website. You can also contact their customer service for assistance with any issues not covered in this manual.

Note: Product specifications and features are subject to change without notice.