1. Introduction
The VU56-PRO is an advanced music spectrum visualizer and audio level meter designed by Douk Audio. It provides a high-resolution, real-time visual representation of audio levels, enhancing your listening experience. Beyond its visualization capabilities, it also functions as an audio converter and splitter, supporting various input and output options.
2. Key Features
- High-Resolution Display: 56 bits per channel, 112-bit stereo display for ultra-high resolution real-time music level status.
- Dual Display Modes: Supports PPM (Peak Programme Meter, 0dB=1.5Vpp) and VU (Volume Unit, 0dB=0.775Vrms) modes for diverse monitoring needs.
- Customizable Visuals: Main bar and peak LED colors can be switched between green and red. Offers 8 distinct display effects for dynamic visual decoration.
- Audio Converter/Splitter: Functions as an audio converter/splitter with RCA and 3.5mm AUX inputs and outputs.
- Gold-Plated Interfaces: All interfaces are gold-plated to ensure tight connections and minimize sound transmission loss.
- Remote Control: Full-function remote control allows easy adjustment of all settings from a distance, with settings saved even after shutdown.
- Compact and Durable Design: Features a cool aluminum CNC black case, solid and durable, with a proper size for various usage scenarios.
- USB Powered: Conveniently powered by USB 5V (≥1A). The power supply is solely for the display and does not affect sound quality.
3. Package Contents
Please check the package carefully for the following items:
- 1 × VU56 PRO Sound Level Meter
- 1 × Remote Control (CR2025 battery not included)
- 1 × USB Cable
- 1 × 3.5mm AUX Cable
- 1 × User Manual
4. Specifications
| Parameter | Value |
|---|---|
| Audio Input | 1 x RCA / 1 x 3.5mm AUX / Microphone |
| Audio Output | 1 x RCA / 1 x 3.5mm AUX |
| Max. Input Level | 2.5Vrms |
| Max. Effective Input Level | 1.8Vrms (Full display when exceeded) |
| Monitoring Frequency Range | 20Hz-20KHz |
| Input Impedance | 10KΩ |
| Brightness Adjustment | 4 levels supported |
| Display Color | Green / Red (Switchable) |
| Display Effects | 8 kinds |
| Remote Control | Supported |
| Display Length Gain | 3 levels adjustable (-3dB, 0dB, +3dB) |
| Display Mode | PPM (Peak Programme Meter) / VU (Volume Unit) |
| Holding Time of Peak LED | Adjustable |
| Drop Speed of Main Bar/Peak LED | Adjustable |
| Working Voltage | DC 5V (≥1A) |
| Power Interface | Micro USB |
| Dimensions (L*W*H) | 154*116*47mm / 6.06*4.57*1.85in |
| Net Weight | 400g / 0.88lb |
| Package Weight | 600g / 1.32lb |
5. Controls and Indicators
The VU56-PRO features a clear LED display and intuitive controls:
- LED Display: Dual-channel (L/R) LED bars showing audio levels from -28dB to +6dB, with a 0VU reference point.
- Rear Panel Controls:
- MODE Button: Short press to switch display effects. Long press (3 seconds) to turn power on/off.
- MIC/LINE Switch: Selects between Microphone input and Line input.
- Microphone Pick-up Hole: Integrated microphone for ambient sound level detection.
- USB 5V IN: Micro USB port for power supply.
- Remote Control: Provides full control over display effects, color, brightness, gain, and power.
6. Setup Instructions
- Power Connection: Connect the provided USB cable to the Micro USB port on the rear panel of the VU56-PRO and plug the other end into a DC 5V (≥1A) power source.
- Audio Input Connection:
- Line Input (RCA/AUX): Connect your audio source (e.g., CD player, MP3 player, computer, phone) to either the RCA "LINE 1 IN" or 3.5mm AUX "LINE 2 IN" ports on the rear panel.
- Microphone Input: If using the built-in microphone for ambient sound detection, ensure the "MIC/LINE" switch is set to "MIC".
- Audio Output Connection (Optional): If using the VU56-PRO as an audio splitter, connect your amplifier or active speakers to either the RCA "LINE 1 OUT" or 3.5mm AUX "LINE 2 OUT" ports.
Note: The inputs and outputs of LINE1 and LINE2 are connected in parallel. You only need to connect one of the inputs and outputs as required.
- Power On: Long press the "MODE" button on the rear panel for 3 seconds, or use the remote control to power on the device.
7. Operation
7.1 Display Modes
The VU56-PRO offers two primary display modes:
- PPM (Peak Programme Meter) Mode: Ideal for dynamic display, showing peak audio levels. (0dB = 1.5Vpp)
- VU (Volume Unit) Mode: More suitable for professional use, indicating average audio levels. (0dB = 0.775Vrms)
7.2 Display Effects and Customization
The device supports 8 kinds of display effects and allows customization of LED colors:
- Switching Effects: Use the "MODE" button on the rear panel (short press) or the remote control to cycle through the 8 display effects.
- Color Selection: The main bar and peak LEDs can be switched between green and red using the remote control.
- Display Gain: Adjust the display length gain to -3dB, 0dB, or +3dB to match your audio signal levels.
- Peak LED Behavior: Adjust the holding time and drop speed of the peak LEDs for desired visual response.
7.3 Video Demonstration
8. Maintenance
- Keep the device clean by wiping it with a soft, dry cloth.
- Avoid exposing the device to extreme temperatures, humidity, or direct sunlight.
- Do not use harsh chemicals or abrasive cleaners.
- Ensure proper ventilation and avoid blocking the vents.
9. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No display/Power off | No power supply or device is off. | Ensure USB 5V power is connected. Long press the MODE button (3s) or use the remote to power on. |
| No audio level display | Incorrect audio input connection or MIC/LINE switch setting. | Check audio cables are securely connected to the correct input (RCA/AUX). Ensure MIC/LINE switch is set appropriately for your input source. |
| Display always full | Input audio level is too high. | Reduce the output volume of your audio source. The effective input level is 1.8Vrms. |
| Remote control not working | Battery missing or depleted. | Insert a CR2025 3V battery or replace the existing one. |
10. User Tips
- For general dynamic visual display, PPM mode is recommended. For more professional audio monitoring, use VU mode.
- Remember to prepare a CR2025 3V battery for the remote control, as it is not included in the package for safety and faster delivery.
11. Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the seller's policies or contact the manufacturer directly. Keep your purchase receipt for any warranty claims.
