Nobsound NS-03G SUB 100W Subwoofer Digital Power Amplifier

1. Introduction

This manual provides detailed instructions for the Nobsound NS-03G SUB 100W Subwoofer Digital Power Amplifier. This compact amplifier is designed to power passive subwoofers, delivering up to 100W of output. It features a simple 3.5mm AUX input and a volume control knob, making it suitable for various audio setups.

Figure 1: Front view of the Nobsound NS-03G SUB Amplifier.

2. Product Features

• Designed specifically for passive subwoofers. Not compatible with active/powered subwoofers or standard speakers.
• Utilizes the TPA3116D2 chip for 100W high power output.
• Features a smooth volume control knob for precise audio adjustment.
• Compact size and durable aluminum alloy casing, ideal for desktop use.
• Equipped with a 3.5mm AUX input for easy connection to various audio sources such as phones, CD players, and TVs.
• Incorporates an NE5532 op amp for low distortion and dynamic balanced sound.

Figure 2: The TPA3116D2 chip, enabling 100W maximum output power.

Figure 3: Internal circuit design featuring the NE5532 op amp for enhanced sound quality.

3. Package Contents

• 1x Nobsound NS-03G SUB Amplifier

Note: A power adapter is NOT included in the package. A high-quality 12V-24V DC power supply (at least 4A) is recommended for optimal performance.

Figure 4: Package contents and amplifier dimensions.

4. Setup and Installation

1. Connect Power Supply: Connect a 12V-24V DC power adapter (not included) to the 'DC IN' port on the rear panel of the amplifier. Important: Always connect the power adapter to the amplifier first, then plug it into the wall outlet to prevent potential sparks.
2. Connect Audio Input: Connect your audio source (e.g., phone, CD player, TV, PC) to the '3.5mm AUX INPUT' jack on the rear panel using a 3.5mm audio cable.
3. Connect Passive Subwoofer: Connect your passive subwoofer to the 'OUTPUT' terminals on the rear panel. Ensure the positive (+) terminal of the amplifier (red) is connected to the positive terminal of your subwoofer, and the negative (-) terminal of the amplifier (black) is connected to the negative terminal of your subwoofer.

Figure 5: Rear panel connections for audio input, subwoofer output, and DC power.

Figure 6: Visual guide for connecting the amplifier to audio sources and a passive subwoofer.

Setup Video

Video 1: An overview of the Nobsound NS-03G SUB Amp and its features, including connection points.

5. Operating Instructions

1. Power On/Off: Turn the 'VOL' knob clockwise to power on the amplifier. The red 'POWER' indicator light will illuminate. To power off, turn the 'VOL' knob fully counter-clockwise until it clicks.
2. Adjust Volume: Rotate the 'VOL' knob clockwise to increase the subwoofer volume and counter-clockwise to decrease it.

Figure 7: Front panel controls, including the Power Indicator and Power/Volume Knob.

6. Maintenance

• Keep the amplifier in a clean, dry environment, away from direct sunlight, heat sources, and moisture.
• Clean the exterior with a soft, dry cloth. Do not use harsh chemicals or abrasive cleaners.
• Do not attempt to disassemble or modify the amplifier, as this will void the warranty and could cause damage or injury.

7. Troubleshooting

• No Power: Ensure the power adapter is securely connected to both the amplifier and a working wall outlet. Verify that the power adapter meets the recommended specifications (12V-24V DC, at least 4A).
• No Sound: Check all audio input and output connections. Ensure the 3.5mm AUX cable is fully inserted and the subwoofer is correctly wired to the output terminals. Confirm the volume knob is not set to minimum.
• Distorted Sound: Reduce the volume level. Check the impedance of your passive subwoofer to ensure it is within the recommended 4-8 ohm range. An underpowered power supply can also cause distortion; ensure it meets the recommended current (at least 4A).
• Sparks when connecting power: It is a known characteristic for some amplifiers to produce a small spark when the power adapter is plugged into the wall after being connected to the device. To minimize this, always connect the power adapter to the amplifier first, then plug the adapter into the wall outlet.
• Power cuts off at high volume: This may indicate that the power supply is insufficient or the subwoofer's impedance is too low for the amplifier at high output levels. Ensure you are using a power supply that meets or exceeds the recommended 12V-24V DC, 4A specifications, and that your subwoofer's impedance is appropriate.

8. Specifications

9. Warranty and Support

For any questions, technical assistance, or warranty inquiries regarding your Nobsound NS-03G SUB amplifier, please contact Nobsound customer support. Our team is dedicated to providing prompt and helpful service.

Product Demonstration Video

Video 2: A brief demonstration of the Nobsound NS-03G SUB amplifier in use.