DOUK AUDIO VU56 PRO

Introduction

The VU56 PRO is an original and upgraded music spectrum display designed by Douk Audio. It features a 56-bit per channel, 112-bit stereo display with ultra-high resolution, allowing real-time visualization of music levels and dynamic decoration of your listening experience. It supports various display effects for enhanced enjoyment.

1. Display Modes: Offers two display modes: PPM (peak programme meter, 0dB=1.5Vpp) and VU (volume unit, 0dB=0.775Vrms), with switchable green or red main bar and peak LED colors. It also supports 8 kinds of display effects for versatility.
2. Design & Connectivity: Features a unique and attractive design, including MIC pick-up. It can also function as an audio converter/splitter with RCA and 3.5mm AUX inputs and outputs. All interfaces are gold-plated to ensure tight connections and reduce sound transmission loss, providing both visual and auditory appeal.
3. Remote Control & Power: Includes a full-function remote control for easy adjustment of all settings from a distance, with settings saved automatically. Powered by USB 5V, it's convenient for desktop, office, or studio use. The power supply is solely for reading the sound signal for display and does not affect sound quality.
4. Construction: Features a proper size with an exquisite appearance, cool aluminum CNC black case, ensuring solidity and durability. Multi-function settings meet various usage requirements. The 112-bit LED indicators and switchable color design offer an amazing and dynamic look, compatible with most common audio devices.

Warm Tips

1. Input/Output Parallel Connection: LINE1 and LINE2 inputs/outputs are connected in parallel. For example, if LINE 1 RCA input is connected, both LINE 1 RCA output and LINE 2 3.5mm AUX output will work. If LINE 2 RCA and LINE 2 3.5mm AUX inputs are connected, audio signals from both channels will be mixed. The VU56 PRO is not suitable for mixing audio signals; avoid this connection.
2. Remote Control Distance: Due to the light-shielding plate on the front panel, the recommended distance for the remote control is within 2 meters.
3. Audio Input Signal: The audio input signal should only be connected to the audio output of ordinary players such as CDs, computers, mobile phones, MP3 players, etc.

Front & Back Panel Overview

The VU56 PRO features clearly labeled inputs and outputs for versatile connectivity.

Scale Value on the Panel

The scale values on the panel correspond to specific input levels, primarily for standard 1/2/3 display modes:

• -3dB corresponds to 0.387Vrms
• 0dB corresponds to 0.775Vrms
• +3dB corresponds to 1.092Vrms

Note: A 1-bit error may exist in these measurements.

Input/Output Diagram Description

The device features LINE 1 and LINE 2 inputs/outputs, a MODE switch, MIC input, and a USB 5V IN port. The inputs and outputs of LINE1 and LINE2 are connected in parallel, meaning only only one input/output needs to be connected for operation.

Front Panel Controls:

• Switch Display Effects / Power On & Off: Long press for 3 seconds to turn off.
• Microphone Pick-up Hole: For audio input via microphone.
• USB 5V IN: Power input.
• LINE / Microphone Switch: Toggles between line input and microphone input.

Back Panel Connections:

• LINE 1 IN/OUT (RCA): For audio input/output via RCA cables.
• LINE 2 IN/OUT (3.5mm AUX): For audio input/output via 3.5mm AUX cables.

The device also includes CE, FC, and RoHS compliance markings.

8 Kinds of Display Effects

The VU56 PRO offers 8 distinct display effects, with values on the scale panel primarily supporting standard 1/2/3 display modes.

Functions of Remote Control

The remote control provides comprehensive functionality for managing the VU56 PRO's settings and display modes.

1. Reset Factory Data: Resets all settings to default.
2. Set Color of Main Bar: Changes the color of the main bar display.
3. Brightness Adjustment: Adjusts the overall display brightness.
4. Drop Speed of Main Bar: Controls how quickly the main bar falls.
5. Drop Speed of Peak LED: Controls how quickly the peak LED falls.
6. Set Holding Time of Peak LED: Adjusts how long the peak LED remains displayed.
7. Input Switch: Toggles between Line input and built-in MIC input.
8. Set the Type of Display Effects: Selects one of the 8 display effects.
9. Set the Color of Peak LED: Changes the color of the peak LED.
10. Gain Setting of Main Bar Display Length: Adjusts the length of the main bar display. (Note: This only affects the display and does not impact sound.)
11. Shortcut Key for Switching Display Effects: Quickly cycles through display effects.
12. VU Display Mode / PPM Display Mode: Toggles between VU (volume unit) and PPM (peak programme meter) display modes.

How to Use

1. Power On: The VU56 PRO automatically powers on when connected to a USB power cable.
2. Connect Inputs and Outputs:
   • Microphone Input: If you have set the input to line, press the LINE/MIC button to switch to MIC, then place the device near your speaker to pick up music.
   • LINE Input: Press the MIC/LINE button to switch to LINE input. Select the correct input and output interfaces based on your audio device. After all connections, play music from your audio source device to enjoy the sound level display.

   The VU56 PRO can also function as an audio switcher, supporting various configurations:

   • RCA input ↔ RCA output
   • 3.5mm AUX input ↔ 3.5mm AUX output
   • RCA input ↔ 3.5mm AUX output
   • 3.5mm AUX input ↔ RCA output
3. Display Effects Control: The 8 kinds of display effects can be freely switched using the remote control or the "SET" button on the back panel. The remote control offers more functions for enhanced enjoyment.
4. Power Off: After use, long press the power button to turn it off, then disconnect the USB power cable.

Frequently Asked Questions

Q: The VU Meter pointer is moving even when there is no music input.

A: 1. Poor quality USB power supply with large ripples can cause significant interference. It is recommended to use a better USB power supply.
2. The music player itself may cause noise and interference. Players with built-in Wi-Fi or Bluetooth functions might interfere. Try changing to another player or turning off wireless/Bluetooth functions.

Q: Why is the level measured by VU56 PRO different from other level meters?

A: 1. Measurement results can be influenced by the audio source device, audio cable, output power, etc. Minor errors (about 1 bit) may occur. For more accurate measurements, professional equipment is recommended.
2. Each level meter has its own 0dB standard. The parameters for VU56 PRO are:

• In VU meter mode: 0dB scale corresponds to 0.775Vrms.
• In PPM mode: 0dB corresponds to 1.5VPP.

If these do not apply, consider other types of level meters.

Q: When using the microphone pickup, the LED lamps show too much or too little.

A: 1. The microphone pickup effect depends on the distance between the microphone and the sound source (speaker), and the speaker's loudness. Adjust the distance between VU56 PRO and the speaker, or adjust the sound volume.
2. Fine-tune the LED display height using the gain adjustment on the remote control. Note that the -3dB and +3dB functions can only be used once and do not accumulate. Even if +3dB is pressed multiple times, only one +3dB function will be applied.
3. If the sound is too loud and you wish to avoid moving the device, cover the microphone pickup hole with a small amount of tape to reduce loudness and keep the VU56 PRO display within the appropriate range.

Parameters