The rationale for pre-processing with I/O plugins is that it's a more
lightweight way to do it as compared to busses. Much of that is because busses
have automatable parameters such as fader and panner positions, as well as
- plugins' parameters. Evaluating automation (even when there's none) is
- expensive in terms of CPU use. However I/O plugins are not automatable, so
+ plugins' parameters. Evaluating parameter automation (even when there's none)
+ adds additional load to the CPU. However I/O plugins are not automatable, so
there's no evaluation happening. As far as Ardour is concerned, they are
almost like JACK audio server clients running alongside Ardour.
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