Using the A/B Switch plugin in Ardour and Mixbus

13 December 2025

The A/B Switch plugin for Ardour and Mixbus is a handy little utility plugin. It allows you to switch between two different plugins in the same channel, for comparison. You can also automate it to switch between those two plugins (or two instances of the same plugin, like an EQ) during mixing.

One application of this plugin is where you need to change the EQ in a channel during the mix. For example, if you have a spot mic channel that is used for two different instruments during the recording of multiple pieces. (This assumes that you're mixing all the pieces in a single session.) You can put two instances of a parametric EQ, each with different settings, in the channel and switch between them with a single automation lane in the A/B Switch.

In this video, I demonstrate how to set up the A/B Switch, including automation. I also demonstrate how a compressor can increase your ambient noise when recording voiceover in a less-than-ideal environment.

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