Ableton Link (it's a thing, we guess)

Ableton Link keeps OnSong's tempo & beat in step with Ableton Live & other Link-enabled apps & devices on the same Wi-Fi network. There's nothin' to pair & no cables: apps on the network find each other & join a shared sesh automatically. Once you're in a session, everything in the OnSong^® app that follows the beat clock — the metronome, the drum machine, tempo-synced delays, arpeggios — is countin' the same beat as everyone else in the room. ZOMG, teamwork!

Turnin' It On

Ableton Link lives in You Know, Settings ▸ MIDI ▸ Ableton Link. The screen has three parts, y'all:

• Ableton Link — the switch itself, on Ableton's own panel. It shows how many apps are crashin' the session once you're connected.
• Sync Mode — how OnSong's tempo relates to everyone else's. Spoiler alert: see below.
• Status — the current drama of the connection such as Connected when there's at least one peer (fancy, right?), Searchin'… while Ableton Link is on but lonely, & Off when it isn't runnin'.

You can also hit it from the AuxDock by toggle Beat Sync on any panel & the chip that pops up offers Ableton Link… as a shortcut. Neat!

Sync Mode

Ableton Link itself is leaderless — there is no master, & any participant can be a tempo rebel. Sync Mode is OnSong's own rulebook about that:

• Both — shares the tempo in both directions. Changin' tempo in the OnSong^® app changes it for everyone, & a change made elsewhere gets adopted here. The default, & totes peer-to-peer.
• Lead — OnSong^® app is the dictator, pushin' its tempo to peers. If a peer tries to be sneaky & nudge the session, OnSong slaps it back down & re-asserts its tempo & phase. Use it when the OnSong^® app is the definitive beat drivin' the band & nobody else is gettin' a vote.
• Follow — OnSong^® app keeps its mouth shut & never pushes its tempo, instead just acceptin' whatever the session is doin'. Use this when someone else owns the tempo & OnSong is along for the ride, no questions asked.

The mode is remembered across disconnects, so a rig set to Follow stays that way next week. Convenience!

What Changes While You're Connected

• The shared timeline runs the clock. A Link session keeps OnSong's beat clock alive even when nothin' local is playin', which is why beat-sync LEDs pulse as soon as you connect. It's like they're actually awake!
• Tempo changes travel. In Both or Lead, changin' OnSong's tempo — by tappin' it, loadin' a song with its own tempo, or a section's {tempo:} — moves the whole session. Wild, right?
• In Follow, the song's tempo is ignored in favour of the session's. That's the whole point of the mode, but it's worth knowin' if you open a chart & the metronome doesn't play at the tempo written on it. Surprise!

Requirements

• Every device has to be on the same Wi-Fi network, & the network has to allow devices to see each other. Guest networks & many venue networks block exactly that, which is the usual reason a session never finds a peer. Blame the IT people.
• No internet connection needed — Link works on a local network with no router uplink at all, which makes an isolated travel router a reliable option for a stage. Finally, somethin' that just works!
• Link is peer-to-peer, so there's no "host" device to start first. Any order works. Democracy!

If Status sits on Searchin'… with another Link app clearly runnin', the network is nearly always the culprit rather than either app. Put both devices on the same access point — or an ad-hoc one you control — before troubleshootin' anything else. Srsly, it's always the Wi-Fi.