Noise-Gate vs Expander: What's the Difference?

dynamic processors

Noise-Gates vs Expanders: What's the Difference?

In the realm of audio engineering and music production, it is essential to understand the differences between various tools and techniques. Noise-gates and expanders are two commonly used devices that serve distinct purposes in shaping the dynamics and clarity of audio signals in your mix. While both tools are designed to control unwanted noise, they operate in different ways and yield unique results. This article looks into the key differences between noise-gates and expanders, exploring how each device functions within a home studio DAW so you can make informed decisions when it comes to optimizing your mixing process.

Key Takeaway: The main difference between a noise-gate and an expander is the amount of gain reduction they provide.

Also read: 10 Mistakes I Made While Learning How To Mix Songs

Understanding Noise-Gates

Function:
- A noise gate plugin is a tool used in audio production to reduce unwanted background noise by cutting off the signal below a certain threshold.
- When the input level falls below this threshold, the gate closes, effectively muting the sound until it rises above the set threshold again.
Operation:
- Noise gates work based on an adjustable parameter called the "threshold" level.
- This setting determines how loud a signal must be before it is allowed to pass through the gate without being attenuated.
Application:
- Musicians commonly use noise gates in recording studios and live performances to minimize amplifier hiss or other ambient noises between notes.
- During the mixing process, they help clean up tracks by removing any unintended background sounds that may have been captured during recording.

⭐️ Learn Ableton Live & make your first song in 90 min. with my Free Online Ableton Live Course ⭐️

Understanding Expanders

What are expanders? Expanders are audio processing tools that work by increasing the volume of audio signals above a certain threshold level. This helps to amplify quieter sounds, making them more audible in the mix. Expanders can also be used as a lighter version of a noise gate (See downward expander below).

Types of expanders:

Upward Expander: Boosts the volume of audio signals that exceed the threshold level, enhancing dynamic range and bringing out subtleties in sound.
Downward Expander: Reduces the volume of audio signals below the threshold level, helping to eliminate background noise or unwanted sounds.

While noise-gates cut off sound entirely when it falls below a set level, expanders increase the volume when it exceeds a particular threshold. Upward expanders boost quieter sounds for more clarity and depth, while downward expanders reduce unwanted noise for cleaner audio recordings.

Key Differences in Operation

Amount of Reduction

Noise-gates and expanders differ in the amount of reduction they provide. Noise-gates completely mute or reduce the audio signal when it falls below a set threshold, effectively eliminating unwanted noise during silent periods. On the other hand, expanders attenuate the audio signal by a predetermined ratio, allowing for more subtle noise reduction without fully cutting off the sound.

Ratio of Operation

In terms of operation ratio, noise-gates have a higher ratio compared to expanders. This means that noise-gates are more aggressive in cutting off signals below their set threshold, resulting in a sharper reduction in sound levels. Expanders, with their lower ratio operation, offer a gentler approach by only reducing the volume slightly when signals fall below the specified level.

Precision vs Flexibility

Noise-gates are known for their precision in completely removing noise during silent intervals but can sometimes lead to abrupt changes in sound levels if not properly adjusted. Conversely, expanders provide more flexibility by reducing noise gradually and allowing for smoother transitions between audio signals. Depending on your specific needs and preferences, you may choose one over the other based on these key differences in operation.

⭐️ Download all of my Music Production Guides for FREE ⭐️ It took me years to learn this stuff!

Adjusting Thresholds and Ratios

Set the threshold on a noise gate to determine when it should open or close. This controls the level at which the gate kicks in, cutting off sound below that point.
Adjust ratios on an expander to control how much gain reduction is applied once the signal falls below the threshold. This allows for more subtle dynamic adjustments.
Experiment with different thresholds and ratios to find the right balance for your audio needs. It may take some trial and error to achieve optimal results.

By fine-tuning these settings, you can effectively manage unwanted noise in your recordings while maintaining natural dynamics in your audio signal.

Adjusting Attack And Release Times

Attack Time: The attack time on a noise gate or expander determines how quickly the device reacts to incoming signals. A shorter attack time will close the gate faster, cutting off any unwanted noise abruptly. On the other hand, a longer attack time will allow some of the initial transient sound to pass through before attenuating.
Release Time: The release time controls how long it takes for the gate or expander to open back up after closing. A shorter release time will result in a quicker return to normal operation once the input signal falls below the threshold. Conversely, a longer release time can create a more gradual opening of the gate, which might be beneficial for smoother transitions between silenced and active audio.

You can customize your sound processing to achieve optimal results for eliminating unwanted noise while preserving desired audio elements effectively.

⭐️ Download my Free Magic Reverb settings Guide ⭐️

Using Noise Gates And Expanders In Your Mix

Expander for Vocals, Synths, and Long Decay: When working with vocals, synths, or any sound with a longer decay that you want to enhance rather than cut off abruptly, an expander is the ideal tool. Expanding the dynamic range of these elements can help bring out subtle nuances and add depth to your mix.
Gates for Drums and Abrupt Muting: On the other hand, when dealing with drums or any element that needs to be muted abruptly without any lingering noise or bleed from other tracks, a noise gate is the way to go. By setting precise thresholds and attack/release times, gates can cleanly cut off unwanted sounds while preserving the integrity of your mix.

Experiment with both noise gates and expanders in different scenarios to understand their unique capabilities and how they can elevate your music production.