
Rast Sound is offering its Lumo loudness enhancer for free (usually €79) until February 24, 2025.
Lumo is a 64-bit only macOS and Windows release for AU, VST3, and AAX.
The plugin enhances loudness using a multi-stage psychoacoustic method. The developer states this method adds depth, warmth, and clarity while preserving dynamics and avoiding limiting artifacts.
The plugin adds headroom to a track while maintaining dynamic range.
Rast Sound produced a YouTube demo that showcases the plugin’s capabilities, with a few examples of the parameters in action.

Looking at Lumo, I first noticed that it has a very minimalist control scheme.
Lumo has Effect, Character, and Output controls on the main panel, as well as oversampling and soft clipping switches.
Effect controls the amount of loudness added, while the Character control allows you to take a track from transparent to beefed up with added harmonics, warmth, or sparkle.
Users can choose between two and four times oversampling, which reduces aliasing and preserves a pristine high end, particularly when running Lumo at higher settings.
Soft Clipping can tame spiky transients and warm-up sounds (you may notice a theme here), which is ideal for hot tracks or masters.
It seems to me that Lumo has a big focus on keeping the whole workflow simple, which is a smart approach for a loudness enhancer.
Getting your tracks and master to the right volume while maintaining audio quality can be a bit of a hassle, so I can definitely see the use case for Lumo in helping to speed up that process.
Rast Sound states that the plugin “avoids any compression” and that it operates via a multi-stage algorithm that intelligently reshapes the audio dynamics.
I’m a bit skeptical about the claim of avoiding any compression. I’m no expert, but I can’t see how the plugin could achieve what it does without using any form of compression whatsoever.
But that aside, the results the plugin delivers sound good and I could definitely see how it’d be a handy option to have in the toolkit.
To pick up your free copy of Lumo, click the ‘Get it free now’ button on the product page and fill out the cart, which requires only an email and name.
You’ll then be forwarded to a page that lists your Lumo license key and has links to the macOS and Windows installers.
The plugin requires a one-time online activation at first and then can operate offline thereafter.
Check out the deal: Lumo (FREE until February 24 – email required)
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