A monitor controller is the central part of any mastering setup. We use it all the time when comparing the master to the original mix while mastering. We also use it for listening to the sum and difference signals, among other things.

The SM Monitor Controller was originally developed in our mastering studio. For many years, we used it alongside a traditional hardware tool. With clients in the studio, the hardware option was often more practical—allowing for quick A/B comparisons with the press of a button, no need to fiddle with the computer. But over time, we noticed just how superior this plugin was. By 2017, we had fully transitioned to the plugin in our workflow.

We’ve experienced firsthand the transformative power of removing loudness bias with automatic loudness matching, rather than less precise manual loudness matching. Loudness bias can make tasks like EQing and evaluating transients or artifacts much more challenging. By eliminating this bias, the entire mastering workflow becomes clearer and more manageable.

While it’s not perfect (understanding nuances like global vs. local loudness matching is essential), it’s the best tool we’ve encountered for truly hearing what you’re doing. It also closes the feedback loop necessary to refine your listening skills over time.

If your setup doesn’t include loudness matching and you’re mastering audio, this tool is a no-brainer. Even if you’re working in a more traditional mastering environment with hardware, we recommend giving it a try—it might just surprise you.

The plugin is currently being developed and we plan to release it in 2025. The macOS/Reaper version is already finished, with only minor tweaks in the GUI ahead.

The Windows version is also finished but the installer is not yet signed (we’re working on that during the Early Access period). This means that an additional warning will be shown before installing and that some anti virus software may show a false-positive warning. The macOS installer is signed and notarized.

The rest of the early access period will be dedicated to getting everything working properly in more DAWs.