Topping A90 Discrete Fully Discrete Balanced Headphone Amplifier
User Manual
Introduction
The Topping A90 Discrete is a fully discrete balanced headphone amplifier and preamplifier. It offers high power output and exceptional audio performance, utilizing NFCA technology for superior sound quality.
Features
- Fully discrete NFCA headphone amplifier
- Balanced and single-ended inputs and outputs
- High power output: 9800mW x 2 into 16Ω
- Selectable gain settings
- Preamp function with volume control
- Multiple headphone output options: 4-pin XLR, 4.4mm, 6.35mm, 3.5mm
- Extender input and preamp output
Specifications
| Parameter | Balanced Output | Single-ended Output |
|---|---|---|
| Power (16Ω) | 9800mW | 2500mW |
| Power (32Ω) | 7000mW | 1250mW |
| Power (300Ω) | 1000mW | 125mW |
| THD+N (@1kHz) | < -123dB (A-weighting) | < -123dB (A-weighting) |
| SNR (@1kHz) | > 131dB (A-weighting) | > 126dB (A-weighting) |
| Channel Separation (@1kHz) | > 130dB | > 120dB |
| Input Impedance | 10kΩ (XLR), 20kΩ (RCA) | 10kΩ (XLR), 20kΩ (RCA) |
| Output Impedance | < 0.1Ω | < 0.1Ω |
| Frequency Response | 20Hz - 100kHz (±0.1dB) | 20Hz - 100kHz (±0.1dB) |
| Gain | +6.0dB, +16dB, +26dB | +6.0dB, +16dB, +26dB |
| Power Consumption | 27.0W | 27.0W |
| Standby Power | < 0.5W | < 0.5W |
| Dimensions | 170mm x 138mm x 45mm | 170mm x 138mm x 45mm |
| Weight | Approx. 570g | Approx. 570g |
Front Panel
The front panel features:
- Power Button: Turns the unit on/off.
- Volume Knob: Adjusts the volume level.
- Headphone Outputs: 4-pin XLR, 4.4mm, 6.35mm, 3.5mm
- Gain Switch: Selects the gain level (+6dB, +16dB, +26dB).
Rear Panel
The rear panel includes:
- Inputs: XLR (Balanced), RCA (Single-ended)
- Pre-out: XLR (Balanced), RCA (Single-ended)
- Extender Input: For connecting to other Topping devices.
- Power Input: Connect the included power adapter.
Operation
- Connect your headphones to the desired output on the front panel.
- Connect your audio source to the appropriate input on the rear panel (XLR or RCA).
- Connect the power adapter and plug it into a wall outlet.
- Press the power button. The unit will turn on.
- Adjust the volume using the volume knob. Start with a low volume and gradually increase it.
- Select the appropriate gain setting based on your headphones' sensitivity and impedance.
- If using the unit as a preamplifier, connect its Pre-out to your power amplifier or active speakers.
Troubleshooting
No sound: Ensure all connections are secure. Check that the volume is not muted or set too low. Verify the correct input source is selected.
Distorted sound: Reduce the volume level. Ensure the gain setting is appropriate for your headphones.
Hum or noise: Try plugging the unit into a different power outlet. Ensure audio cables are not running parallel to power cables.
Maintenance
Keep the unit clean and dry. Avoid exposing it to extreme temperatures or humidity. Use a soft, dry cloth to clean the exterior.
Safety Information
- Read all instructions before use.
- Do not expose the unit to water or moisture.
- Do not open the casing; refer servicing to qualified personnel.
- Use only the provided power adapter.
Warranty
Refer to the warranty card included with your product for details on warranty coverage and registration.
