The Essentials
VU in VU meter stands for “Volume Unit”. Here’s more.
A VU meter is used to measure the average level of audio signals and ensure that the signal is not too loud or too quiet to prevent distortion.
The main differences between a PPM and a VU meter are their response time and calibration. For additional info click here.
Do you know what a VU meter is? No? Well, luckily for you, you’re about to find out. In this article, we’ll discuss what a VU meter is, how it works, and how it’s used. We’ll also deep-dive into its advantages and explain the differences to a PPM.
Table of Contents
What is a VU meter?
If you’re involved in music recording or broadcasting, you’ve probably come across a VU meter.
What is a VU meter?
A VU meter is an analogue device that measures the average level of an audio signal. It’s designed to respond to the loudness of the signal rather than its peak level. Thus, it’s commonly used in music production, broadcasting and live sound reinforcement.
And what does the VU stand for? The VU in VU meter resembles the “Volume Unit“. It’s a measure of the loudness of an audio signal, specifically the average level of the signal over time, and is calibrated in decibels (dB).
Originally developed by Bell Labs in the 1930s for use in the telephone industry, the VU meter has since become a standard tool in music production, broadcasting and live sound reinforcement.
Did you know…?
There’s also something called VU meter plug-ins. A VU meter plug-in is a software plug-in that emulates the functionality of a physical VU meter. It’s typically used in digital audio workstations (DAWs) to provide a visual representation of the average level of an audio signal. VU meter plug-ins can also be used to add a vintage or classic aesthetic to the DAW interface.
How does a VU meter work?
A VU meter is an analogue device that measures the average level of an audio signal. It was developed by Bell Labs in the 1930s for use in the telephone industry. The VU meter is designed to respond to the loudness of the signal rather than its peak level. This means that the VU meter measures the loudness of the signal over time, giving a more accurate representation of how loud the signal is perceived by the human ear.
The VU meter is calibrated in decibels (dB), a logarithmic scale used to measure the intensity of sound. The zero dB point on a VU meter represents the maximum level before distortion occurs.
In general: The VU meter has a range of -20 dB to +3 dB, although the ideal operating range is between -10 dB and 0 dB.
Applications of VU meters
VU meters are commonly used in music production to monitor the level of audio signals. They are used to ensure that the signal is not too loud or too quiet and to prevent distortion. VU meters are also used in broadcasting to ensure that the signal is at the correct level for transmission.
- Music Production: VU meters are commonly used in music production to monitor the level of audio signals. They are used to ensure that the signal is not too loud or too quiet and to prevent distortion. VU meters are often included with mixing consoles, audio interfaces and recording software to allow producers and engineers to monitor levels during the recording and mixing process.
- Broadcasting: In broadcasting, VU meters are used to ensure that the signal is at the correct level for transmission. They are used to monitor the audio signal and prevent it from distorting or clipping. This is important in radio and television broadcasting, where the audio signal is transmitted to a large audience.
- Live sound reinforcement: In live sound reinforcement, VU meters are used to monitor the level of the audio signal and prevent feedback. Feedback occurs when the sound from the speakers is picked up by the microphone and re-amplified, creating a loop of increasing volume. By monitoring the level of the signal with a VU meter, the sound engineer can adjust the volume to prevent feedback.
Types of VU meters
There are two types of VU meters: the analog VU meter (the mechanical VU meter) and digital VU meter (the LED/LCD VU meter)
The main difference between an analog and a digital VU meter is the way they display the audio signal.
Analog VU meters use a physical needle that moves across a scale to indicate the level of the audio signal. They are often used in vintage or classic equipment and can give a warm and pleasant aesthetic to the user. However, they are susceptible to calibration drift and may require regular adjustment to maintain their accuracy.
Digital VU meters, on the other hand, use LEDs or LCDs to display the level of the audio signal. They are often more accurate than analog meters and can display multiple channels simultaneously. They are also less susceptible to calibration drift and require little or no maintenance.
For example
One popular example of a digital VU meter is the Waves VU Meter plug-in.
The Waves VU Meter plug-in is a digital VU meter that uses a virtual needle to display the level of an audio signal. It works by analysing the incoming audio signal and calculating its average level over a short period of time, typically around 300 milliseconds. The level is then displayed on the virtual needle, which moves in response to changes in the signal’s level.
The Waves VU Meter plug-in also includes a calibration feature that allows the user to set the meter to match the specific characteristics of their equipment. This is important because different devices can have different sensitivities, and calibration ensures that the meter provides an accurate representation of the loudness of the signal.
Advantages of a VU meter
Prevents distortion
One of the main benefits of using a VU meter is that it helps to prevent distortion in audio signals. By monitoring the average level of the signal over time, a VU meter ensures that the signal is not too loud or too quiet, preventing distortion or clipping.
Side Note: This is particularly important in music production, where distortion can ruin a recording or mix.
Helps achieve optimum recording levels
Another benefit of using a VU meter is that it can help you achieve optimal recording levels. A VU meter can be used to monitor the levels of audio signals during recording to ensure that they are not too loud or too quiet.
Side Note #2: This helps to ensure that the recording has a good signal-to-noise ratio and provides a solid basis for further processing.
Improves sound quality
Using a VU meter can also improve the sound quality of an audio signal. By ensuring that the signal is at the correct level, a VU meter ensures that the audio signal has a good balance between the loud and soft parts. This makes the audio signal more pleasant to listen to and improves the overall sound quality.
Provides accurate monitoring
A VU meter provides accurate monitoring of audio signals, allowing sound engineers to make informed decisions about the audio signal. By providing a more accurate representation of how loud the signal is perceived by the human ear, a VU meter helps sound engineers make adjustments to the audio signal to improve its quality.
Easy to use
One of the benefits of using a VU meter is that it’s easy to use. It doesn’t require any special training or knowledge to use, making it accessible to anyone who needs to monitor audio signals. It’s also a relatively inexpensive tool, making it an affordable option for small studios and live sound setups.
Compatible with a wide range of equipment
A VU meter is compatible with a wide range of equipment, including mixing consoles, audio interfaces and recording software. It can be connected to a variety of audio devices, making it a versatile tool for monitoring audio signals.
What is a mixing console?
A mixing console, also known as a mixing desk or audio mixer, is a device used in music production and live sound reinforcement to combine and manipulate audio signals from different sources.
It typically consists of several channels, each with its own inputs and controls for adjusting the volume, tone and effects of the audio signal. The mixer allows sound engineers to blend multiple audio signals to create a balanced mix that can be recorded or amplified for a live performance.
PPM vs. VU meter
What is a PPM meter?
A PPM meter is a type of audio meter that measures the peak level of an audio signal. It’s often used in broadcasting and music production to ensure that the signal isn’t clipping or distorting.
Differences between PPM and VU meters
- Response time: VU meters have a relatively slow response time and are designed to measure the average level of the signal over time. This means they don’t react quickly to sudden changes in level. PPM meters, on the other hand, have a fast response time and are designed to measure the peak level of the signal. This means that they respond quickly to sudden changes in level.
- Calibration: VU meters are calibrated in decibels (dB) and have a range of -20 dB to +3 dB, although the ideal operating range is between -10 dB and 0 dB. PPM meters are also calibrated in decibels, but typically have a range of -10 dB to +8 dB. This allows them to measure peak levels more accurately.
- Typical applications: VU meters are commonly used in music production, broadcasting and live sound reinforcement to monitor the level of audio signals and prevent distortion. They are ideal for monitoring the overall loudness of a signal over time. PPM meters, on the other hand, are used primarily in broadcast and music production to monitor the peak level of the signal to prevent clipping or distortion.
- Type of meter: VU meters are analogue devices that use a needle to indicate the level of a signal. PPM meters, on the other hand, can be either analogue or digital and use LEDs or LCDs to display the level of the signal.
In short: VU meter
A VU meter, or volume unit meter, is a device used to measure the average level of audio signals. It’s commonly used in music production, broadcasting and live sound reinforcement to prevent distortion, achieve optimum recording levels, improve sound quality and provide accurate monitoring. There are two types of VU meters: mechanical and LED/LCD. A VU meter is an essential tool for anyone working with audio signals.
FAQ: VU meter
A VU meter can read the average level of audio signals over time.
A 0VU represents a level of +4 dBu or 1.228 volts RMS.
A kick drum on a VU meter should be between 0 and +3 VU, which corresponds to around -18 to -12 dBFS. However, it’s important to note that this can vary depending on the specific mixing/mastering style and personal preference of the engineer.