Integrated Melodyne pitch correction in PreSonus’ Studio One is made more interesting by the technology behind it. Celemony this week describes a new technology they call ARA, or “Audio Random Access.” The notion is this: rather than just receiving or generating audio signal, the plug-in gets access to audio data. That means you can actually write a plug-in that rewrites the audio content in a recorded DAW track, as Melodyne does in Studio One.

As developer Celemony describes it, “ARA opens an additional channel of communication through which the DAW and plug-in can exchange information about the audio file, tempo, pitch, rhythm and much more, which allows them to work together considerably more closely.”

It’s the ability to exchange audio data information that seems the most compelling. Previously, audio processing plug-ins simply took buffers of audio signal from the DAW. You could “look ahead” further into that signal by increasing the buffer (and thus latency with it), but generally speaking, you’re doing the processing in something that approximates real-time. ARA in the example of Melodyne gives you access to an entire recorded track without having to transfer the audio file to and from the plug-in.

Celemony says this is “an extension of the existing plug-in interfaces,” not a new plug-in format. (If it were the latter, I’d have to point to this xkcd cartoon.) I’m still obligated to express some skepticism about how widely this will be adopted, or if it can be considered a “standard” extension, though they do promise additional vendors soon. (Implementation would seem to be by necessity on a host by host basis – and then once you have the host, a plug-in creator might add support.) It’s a proprietary technology, but then, so are the plug-in formats currently in wide use (AU controlled by Apple for Mac OS, VST by Steinberg, and RTAS by Digidesign, unless we see more of LV2). For now, though, we’ll have to see if the idea itself can extend what a plug-in can do. Check out the videos for more. (no documentation for developers, but there is an email address to use if you’re interested)