TBProAudio has released ISOL8, a freeware mix monitoring tool in VST, VST3, AU, AAX, and RTAS plugin formats for digital audio workstations on PC and Mac.
ISOL8 is a tool designed for monitoring different frequency regions within a mix or a single track. It splits the incoming signal into five frequency bands which can be soloed or muted individually. The crossover frequency can be adjusted manually for each pair of bands.
Apart from the mute/solo switches for its five frequency bands, ISOL8 also features a filter bypass switch, monitoring channel adjustments (solo buttons for the Left, Right, Mid, and Side channels), an output volume control, and an attenuation switch. The channel mode selector on the left is a very useful feature, as it enables the filter mute/solo buttons to target a specific channel. For example, you can mute only the MF signal in the left stereo channel while listening to everything else. Finally, the slope menu is used to set the filter cutoff slope to either 12 dB/oct or 24 dB/oct.
So, essentially, ISOL8 is sort of similar to a multi-band compressor capable of muting or soloing individual frequency bands. However, it is far more streamlined than a multi-band compressor and uses filters that are more suitable for this particular purpose (Linkwitz-Riley crossover filter design). The ability to target specific parts of the signal allows for some very precise monitoring of the mix and can make detecting problematic areas that much easier. It can also be useful for monitoring single tracks containing complex stereo signals. During our test, the plugin used around 2% CPU on our 4th gen i7 processor (on a single CPU core), which is reasonably low for a utility of this type.
The plugin is available for direct free download from the developer’s website, no signup required. It comes as an EXE installer which is a tiny bit cumbersome to use if you’re installing your plugins outside of the default VST plugin directory. Other than that, the download and installation process went very smoothly. The interface was designed by Crimson Merry who also developed our free BPB Cassette Drums plugin bundle.
ISOL8 is available for free download via TBProAudio (2.57 MB download size, ZIP archive containing EXE installer, 32-bit & 64-bit VST/VST3/AU/AAX/RTAS plugin format for Windows & macOS).