Introduction
The Nobsound TUBE-T4C Mini HiFi Tube Preamp is designed to enhance your audio experience by adding warmth and depth to your music. This Class A vacuum tube preamplifier features precise bass and treble controls, allowing you to fine-tune your sound to personal preferences. Its compact and durable design makes it suitable for various home audio and desktop setups. The device supports swappable tubes for sound customization and offers broad compatibility with standard RCA input and output connections.
Figure 1: Nobsound TUBE-T4C Mini HiFi Tube Preamp in a typical home audio setup, showcasing its compact size and glowing tubes.
What's in the Box
- 1x TUBE-T4C Preamp
- 2x 6J5 Tubes
- 1x DC 5V Power Adapter
- 1x User Manual
Figure 2: All items included in the Nobsound TUBE-T4C package: the preamp unit, two 6J5 tubes, a power adapter, and the user manual.
Product Overview
Front Panel Controls
- TRE (Treble Knob): Adjusts high frequencies.
- BASS (Bass Knob): Adjusts low frequencies.
- /VOL (Power Switch / Volume Knob): Turns the unit on/off and controls the overall volume.
Rear Panel Connections
- DC 5V IN (>=2A): Power input for the DC 5V adapter.
- RCA IN (Right/Left): Standard stereo RCA input for audio sources.
- RCA OUT (Right/Left): Standard stereo RCA output to power amplifiers or active speakers.
Figure 3: Detailed diagram of the Nobsound TUBE-T4C's front panel controls (Treble, Bass, Volume/Power) and rear panel connections (DC In, RCA In, RCA Out).
Setup
- Tube Installation: Carefully insert the two 6J5 tubes into their respective sockets on the top of the preamp. Ensure the pins align correctly and push gently until seated.
- Connect Audio Source: Connect your audio source (PC, phone, tablet, CD player, streamer) to the RCA IN ports on the rear panel of the TUBE-T4C using an RCA cable.
- Connect to Amplifier/Speakers: Connect the RCA OUT ports on the rear panel of the TUBE-T4C to your power amplifier or active (powered) speakers using an RCA cable.
- Power Connection: Connect the DC 5V power adapter to the DC 5V IN port on the rear panel, then plug the adapter into a power outlet.
- Power On: Long-press the Volume knob to turn on the unit. Allow the tubes to warm up for about 15 seconds for optimal performance.
Figure 4: Close-up of the rear panel showing the DC 5V power input and RCA input/output connections.
Operating Instructions
- Volume Control: Rotate the Volume knob to adjust the audio output level.
- Bass Adjustment: Use the BASS knob to increase or decrease low frequencies according to your preference.
- Treble Adjustment: Use the TRE knob to increase or decrease high frequencies according to your preference.
Figure 5: The front panel of the TUBE-T4C, highlighting the Treble, Bass, and Volume controls for easy audio adjustment.
Tube Replacement/Customization
The TUBE-T4C features pluggable 7-pin tube sockets, allowing you to customize your sound signature by swapping out the default 6J5 tubes with compatible alternatives. Supported tubes include 6J1, 5654, 6AK5, EF95, and others. Ensure the unit is powered off and unplugged before attempting to replace tubes. Carefully pull out the existing tubes and gently insert the new ones, aligning the pins correctly.
Figure 6: A close-up view of the pluggable tube sockets, demonstrating how tubes can be easily swapped for sound customization.
Troubleshooting
- No Sound:
- Check if the power adapter is securely connected and the unit is powered on.
- Verify that audio input and output cables are correctly connected.
- Ensure the volume is not set to minimum on the TUBE-T4C or your connected amplifier/speakers.
- Confirm that the audio source is playing and its volume is adequate.
- Distorted Sound:
- Reduce the volume on the TUBE-T4C and/or your audio source.
- Check for loose cable connections.
- Ensure the tubes are properly seated in their sockets.
- Humming/Noise:
- Ensure all cables are properly shielded and away from power cables.
- Try using a different power outlet.
- Check for ground loop issues in your audio setup.
Specifications
| Item Weight | 0.634 ounces |
| Product Dimensions | 3.23 x 3.07 x 1.26 inches |
| Item Model Number | XZ-TUBE-T4C |
| Compatible Devices | Active Speaker, Amplifier, CD Player, PC, Phone |
| Connector Type | RCA |
| Material Type | Metal |
| Power Source | Corded Electric |
| Color | Black |
Media Resources
Product Demonstrations
Fosi Audio MC331 Tube Integrated Amplifier with DAC Unboxing
Video 1: This video demonstrates the unboxing and initial setup of the Fosi Audio MC331, a similar tube integrated amplifier. While not the exact TUBE-T4C model, it provides a general idea of the unboxing experience and connectivity for tube amplifiers from a seller.
Fosi Audio P3 Preamp first impression
Video 2: This video offers a first impression of the Fosi Audio P3 Preamp. Although a different model, it showcases the general features and operation of a preamp, which can be helpful for understanding the TUBE-T4C's function.
AIYIMA T1 PRO Tube Preamplifier with RCA/Bluetooth Input B
Video 3: This video demonstrates the AIYIMA T1 PRO Tube Preamplifier, which shares similar functionality and connectivity (RCA/Bluetooth) with the Nobsound TUBE-T4C. It can provide insights into setting up and using a tube preamp.
Warranty and Support
For warranty information and technical support, please refer to the contact details provided in the included user manual or visit the Nobsound official website. Keep your purchase receipt for warranty claims.
