1. Introduction
The Nobsound P32 is a versatile tube headphone amplifier and stereo preamplifier designed to enhance your audio experience. It features a 1000mW output, capable of driving headphones with impedances ranging from 24Ω to 600Ω. The P32 incorporates vacuum tubes to deliver a warm and rich sound signature, and offers customization options through swappable tubes and op-amps. It supports both 3.5mm and 6.35mm headphone outputs, and RCA and 3.5mm AUX inputs for broad compatibility with various audio devices.
Image 1.1: The Nobsound P32 Tube Headphone Amplifier, a compact device with two visible vacuum tubes on top, a volume knob, and headphone jacks on the front panel.
2. Package Contents
Please check the package for the following items:
- 1x Nobsound P32 Headphone Amplifier
- 2x 6J5 Tubes
- 1x DC 5V Power Adapter
- 1x User Manual
Image 2.1: A visual representation of the Nobsound P32 package contents, including the amplifier unit, two 6J5 vacuum tubes, a DC 5V power adapter, and the user manual.
3. Product Overview
3.1 Front Panel
- 6.35mm Headphone Output: For connecting headphones with a 6.35mm plug.
- 3.5mm Headphone Output: For connecting headphones with a 3.5mm plug.
- Power Switch / Volume Knob: Rotate to turn the unit on/off and adjust the output volume.
3.2 Rear Panel
- DC 5V IN (≥2A): Power input port.
- RCA IN (L/R): Stereo RCA input for audio sources.
- AUX IN (3.5mm): 3.5mm auxiliary input for audio sources.
Note: Do not connect both RCA and 3.5mm AUX inputs simultaneously.
Image 3.1: Diagram illustrating the front and rear panels of the Nobsound P32, detailing the 6.35mm and 3.5mm headphone outputs, power/volume knob on the front, and DC 5V power input, RCA L/R inputs, and 3.5mm AUX input on the rear.
4. Setup
4.1 Tube Installation
- Carefully unpack the 6J5 vacuum tubes from their protective packaging.
- Align the pins of each tube with the corresponding holes in the tube sockets on top of the amplifier. Ensure the pins are straight.
- Gently push each tube straight down into its socket until it is firmly seated. Do not force the tubes.
Image 4.1: A close-up view demonstrating the proper installation of a vacuum tube into its socket on the Nobsound P32 amplifier, highlighting the alignment of pins.
4.2 Connecting Audio Sources
Connect your audio source (e.g., PC, phone, TV, CD player) to the P32 using either the RCA input or the 3.5mm AUX input on the rear panel.
- For RCA connection: Use an RCA cable to connect the audio output of your source device to the RCA IN (L/R) ports.
- For 3.5mm AUX connection: Use a 3.5mm audio cable to connect the audio output of your source device to the AUX IN port.
Important: Only use one input at a time. Connecting both RCA and 3.5mm AUX inputs simultaneously is not recommended and may cause audio issues.
4.3 Connecting Headphones or Speakers
- For Headphones: Plug your headphones into either the 6.35mm or 3.5mm headphone output jack on the front panel. Both outputs can be used simultaneously.
- For Active Speakers/Power Amplifier (Preamp Function): Connect the 3.5mm headphone output on the front panel to the AUX/RCA input of your active speakers or power amplifier using an appropriate audio cable.
Image 4.2: The Nobsound P32 connected to both over-ear headphones via the 6.35mm jack and in-ear monitors via the 3.5mm jack, demonstrating its dual output compatibility.
4.4 Power Connection
Connect the provided DC 5V power adapter to the DC 5V IN port on the rear panel of the amplifier, then plug the adapter into a standard wall outlet.
5. Operating Instructions
5.1 Powering On/Off
Rotate the Power Switch / Volume Knob clockwise until you hear a click to turn the amplifier on. Rotate it counter-clockwise until you hear a click to turn the amplifier off.
5.2 Volume Adjustment
Once the amplifier is powered on, rotate the Power Switch / Volume Knob to adjust the output volume to your desired listening level. Start with a low volume and gradually increase it to prevent sudden loud sounds.
5.3 Input Usage
The amplifier automatically detects the active input. Ensure only one audio source is connected to either the RCA or 3.5mm AUX input at a time.
6. Maintenance
6.1 Tube Replacement
The 6J5 vacuum tubes are swappable, allowing for sound customization or replacement if a tube fails. To replace a tube:
- Ensure the amplifier is powered off and unplugged from the power source.
- Allow the tubes to cool down completely if the unit has been in use.
- Gently grasp the tube and pull it straight upwards to remove it from the socket. Avoid twisting.
- Insert the new compatible tube by aligning its pins with the socket holes and pushing it straight down firmly.
6.2 Op-Amp Replacement
The dual op-amp chips are also swappable for further sound tuning. This procedure requires more care and potentially specialized tools (like an IC extractor).
- Ensure the amplifier is powered off and unplugged.
- Carefully open the amplifier casing (refer to manufacturer guidelines if available, or seek professional assistance).
- Using an appropriate tool (e.g., IC extractor), gently pry the existing op-amp chips from their sockets. Note their orientation.
- Align the new compatible op-amp chips with the correct orientation and carefully insert them into the sockets.
- Reassemble the amplifier casing.
Image 6.1: A close-up view of the internal circuit board of the Nobsound P32, showing an op-amp chip being carefully removed or inserted with tweezers, illustrating the swappable op-amp feature.
6.3 Cleaning
To clean the amplifier, use a soft, dry cloth. Avoid using liquid cleaners or solvents, as they may damage the finish or internal components.
7. Troubleshooting
- No Sound:
- Ensure the amplifier is powered on and the volume knob is turned up.
- Verify that the audio source is playing and connected correctly to either the RCA or 3.5mm AUX input.
- Check headphone/speaker connections.
- Confirm that only one input (RCA or AUX) is connected at a time.
- Ensure tubes are properly seated in their sockets.
- Distorted Sound:
- Reduce the volume level from both the amplifier and the audio source.
- Check if the audio source output is too high, causing clipping.
- Inspect cables for damage or loose connections.
- Ensure headphones/speakers are within the recommended impedance range (24-600Ω).
- Humming/Buzzing Noise:
- Ensure all connections are secure.
- Try moving the amplifier away from other electronic devices that might cause interference.
- Test with a different power outlet.
- Ensure the power adapter is the original or a compatible 5V ≥2A adapter.
8. Specifications
| Feature | Specification |
|---|---|
| Product Dimensions | 3.23 x 3.07 x 1.26 inches |
| Item Weight | 7.7 ounces |
| Item Model Number | XZ-P32-AU |
| Connectivity Technology | Auxiliary, RCA |
| Compatible Devices | Amplifier, Headphone, Personal Computer, Speaker, Television |
| Connector Type | 3.5mm Jack, 6.35mm Jack |
| Audio Output Mode | Stereo |
| Surround Sound Channel Configuration | 2 |
| Color | Black |
| Manufacturer | Nobsound |
9. Safety Information
- Do not expose the unit to water or excessive moisture.
- Avoid placing the unit near heat sources or in direct sunlight.
- Do not attempt to disassemble or modify the unit beyond tube and op-amp replacement, as this may void the warranty and pose a safety risk.
- Use only the provided power adapter or a compatible 5V ≥2A power supply.
- Always turn off and unplug the unit before cleaning or performing any maintenance.
- Listen at moderate volume levels to prevent hearing damage.
10. Warranty and Support
Nobsound products typically come with a standard manufacturer's warranty. Please refer to the warranty card included in your package or contact Nobsound customer support for specific warranty terms and conditions.
For technical support, troubleshooting assistance, or further inquiries, please visit the official Nobsound store or contact their customer service department.
Nobsound Store: https://www.amazon.com/stores/DoukAudioNobsound/page/BF750DA6-DED6-4CD9-89C1-1A442DDADDD7
