Wusik offers the Wusik MSTR ($49.95 value) mastering equalizer and spectrum analyzer plugin as a free download for a limited time only.
Wusik MSTR is a multi-band equalizer and spectrum analyzer for audio mastering. It is available in VST, VST3, and AU plugin formats for 64-bit digital audio workstations on Windows and macOS. It’s worth noting that macOS Catalina is also supported. The software can work as a standalone application, too.
See also: Best FREE Mastering SoftwareThe plugin features a retro-looking interface that reminds me of a pre-Winamp era audio players. This is not a bad thing, actually, and I’m kind of digging the design aesthetic. Also, the interface is resizable, which is a much-needed and still too often disregarded feature in modern plugin GUIs.
More importantly, Wusik MSTR is a seemingly rather useful mastering tool. It sports a 3 dB/octave spectrum analyzer and a dual-mode 26-band equalizer, with a limiter in the output stage. The EQ bands cover the 20 Hz – 20 kHz area of the frequency spectrum. With the spectrum analyzer and EQ combo, it could be easier to pinpoint and fix the trouble frequencies in a mix during the mastering stage.
Check out the official demo video embedded below for a quick introduction to Wusik MSTR’s features and workflow.

Of course, the best advice is to always listen to your ears, but a frequency analyzer can help if the listening environment isn’t ideal. And it goes without saying that this is often the case in budget studio setups or bedroom producers’ studios.
Wusik MSTR is an Audio Analyzer and Multi Band Equalizer. The interface features a graphic overview of what the audio looks like under multiple frequency dividers. Starting from 20 HZ up to 20 KHz.
Another helpful feature in Wusik MSTR is the playback of test tones and noises. The plugin can generate pink noise and test tones for calibration purposes. It can also load rendered audio files and loop the entire file or a specified region.
Wusik MSTR is typically priced at $49.95, but you can download it for free from Wusik for a limited time only. There’s no info on when the free download offer will end.
On a related note, Wusik is currently running a site-wide 90% OFF sale on most software. Check out their online store for more info.
UPDATE: It seems that the freebie offer ends on October 19th. Thanks to our reader Arthur for the info!
More info: Wusik MSTR (free for a limited time, available in 64-bit VST/VST3/AU plugin formats for Windows & macOS)
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