Reference · Key and tempo inside a DAW

Does Session™ Key work with Studio One?

Yes, and the permission is optional. Every send writes a tempo-and-key MIDI file ready to drop on the Tempo Track, and a one-time macOS Accessibility grant adds a direct transport set. Only that direct set needs the grant, so denying it costs the direct set and nothing else.

Session™ Key is published by Capiscana, Inc., which operates this site. Studio One is a product of PreSonus, which has no involvement in this page. Facts about Studio One below are dated to the day the source was read.

What gets written into the song

Session™ Key reads the key and BPM from whatever is playing through the Mac's audio output and shows both in the menu bar with a confidence mark on every read. When the reading locks, a send does one thing for certain and a second thing if it has been allowed to.

The certain part is the file. A standard MIDI file carrying the tempo and the key is written on every send, ready to drop straight onto the Tempo Track, and that route asks for no permission at all.

The second part is the direct set. With Accessibility granted once, the transport tempo and key are set inside Studio One and the value is read back to confirm the set landed. Deny the grant and nothing else changes, because the file route works exactly as before.

Detection runs on the device. No audio is uploaded, recorded or stored off the Mac, which is the difference that matters when the track on the timeline is an unreleased record.

The one-time setup

1. Choose Studio One as the DAWThe companion files for the selected DAW install automatically. Studio Pro and legacy Studio One installs sit under the same target.
2. Send with a hotkeyLock a reading and press the send hotkey. The tempo-and-key MIDI file is written every time, ready for the Tempo Track.
3. Grant Accessibility, if the direct set is wantedmacOS asks a single time, in System Settings under Privacy and Security. That grant is what allows an outside app to set the transport tempo and key inside Studio One and read the value back.

What it costs and what it runs on

Common questions

Does Session™ Key work with Studio Pro?

Yes. Studio Pro and legacy Studio One installs are supported under the same target. Every send writes a tempo-and-key MIDI file for the Tempo Track, and with an optional Accessibility grant the transport tempo and key are set directly, confirmed by read-back.

Is the Accessibility grant required for Studio One?

No. The tempo-and-key MIDI file is written on every send regardless, ready to drop on the Tempo Track. The grant is optional and only adds the direct transport set.

Does the audio ever leave the Mac?

No. Key and BPM detection runs entirely on the device, from the Mac's own audio output. Nothing is uploaded, recorded or stored in the cloud.

What does the written file carry?

The tempo and the key, as a standard MIDI file, ready to drop on the Tempo Track. It is written on every send whether or not the direct transport set runs.

How much does it cost?

$49 once, with no subscription. One license covers up to three Macs and carries a 30-day money-back guarantee. A license is also included with the Session Cards™ deck.