Beat Inspector

A Beat Detective–style audio quantizer for Ableton Live, built as a Live Extension. It slices warped audio at its transients and nudges each slice onto the grid — tightening a sloppy take without time-stretching it. Great for live-recorded drums, keys, or any performance you want pulled to the grid while preserving transients and avoiding warping artifacts.

Version 1.1.0 · by Alex Borel · built on the Ableton Extensions SDK (beta)

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What it does

Beat Inspector reads the warp markers on a clip (one per transient), figures out which hit belongs to each grid cell, and rebuilds the clip as a chain of slices with every hit moved onto the beat. Because it cuts and nudges rather than stretches, attacks stay crisp and there's no warping artifact.

It works on three kinds of selection:

• Single clip — right-click an audio clip and quantize just that clip.
• Selection (unlinked) — select a time range across one or more audio tracks; each clip is detected and quantized independently.
• Selection (linked) — phase-lock several mics of the same source (e.g. a drum kit: kick, snare, overheads, room). The hits are pooled across mics, the earliest clean transient per grid cell sets the timing, and every track is moved by the same amount so the kit stays perfectly in phase.

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Requirements

• Ableton Live 12.4.5 or later, with Extensions enabled (the Extensions feature is currently in beta).
• Audio clips that are warped and have warp markers on their transients (see Quick start).

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Install

1. Download beat-inspector-1.1.0.ablx.
2. Install it following Ableton's current instructions for adding a Live Extension (beta).
3. Restart Live if it was already running.

To update later, reinstall the new .ablx and restart Live.

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Quick start

1. Warp the clip. Make sure Warp is on for the audio you want to quantize.
2. Insert warp markers at every transient. In Clip view, select the clip, press Cmd/Ctrl+A (select all), then Cmd/Ctrl+I (Insert Warp Markers). This is the single most important step — Beat Inspector slices on these markers, so without them there's nothing to cut on.
3. Set your grid (e.g. 1/8 or 1/16) — or set it in the Beat Inspector dialog.
4. Run it:
   • For one clip: right-click the clip → Beat Inspector: Quantize Clip.
   • For a range/multi-track: select the time range across the tracks, right-click → Beat Inspector: Quantize Selection.
5. Adjust the settings in the dialog (below) and hit Quantize.

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Settings

• Linked (multi-track selections only) — phase-lock all selected tracks to one shared grid of events. Turn this on for a multi-mic kit; leave it off to quantize each track on its own.
• Quantize grid — the grid hits snap to. Current grid follows Live's grid; or pick 1/4, 1/8, 1/16.
• Detection buffer — how far off the grid a transient can be and still be captured. Auto = half a grid cell.
• Sensitivity — how aggressively transients are detected. Higher catches weaker hits; lower keeps only clean strong attacks (and is more forgiving of long decays / sustained notes).
• Quantize strength — how far each hit moves toward the grid. 100% snaps fully; lower keeps some of the original groove; 0% slices at the transients without moving them.
• Max / Min pre-roll — how far each slice reaches back into its quiet pre-attack to fill the gap before a hit (min is always added; up to max). Useful for closing small gaps cleanly without exposing the previous hit's tail.

Settings are remembered between runs in the same session. Restore defaults resets them.

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Tips

• For multi-mic kits, use Linked — it keeps phase coherence across the mics, which independent quantizing would break.
• Duplicate the track or clip before running. Reverting a quantize currently takes a long multi-step undo chain (see Known limitations), so keeping a duplicate gives you a clean one-move way back to the original.
• If a quantize looks wrong, undo and try a lower Sensitivity (fewer false transients) or a coarser grid.
• You can re-run Beat Inspector on already-sliced material — it works on chopped takes too, not just whole clips — so you can tighten a pass further or move it to a finer grid without starting over.

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Known limitations

• Manual warp markers. Beat Inspector can't insert warp markers itself yet, so adding them (Cmd/Ctrl+A then Cmd/Ctrl+I) is a manual step you do before running it.

• Multi-step undo. Reverting a quantize currently takes several undos (roughly one per slice), not a single Cmd/Ctrl+Z. This is a limitation of the current Extensions SDK beta — clip create/delete don't fold into one undo step — not the extension. A single-undo version is a pending request to Ableton. (Tip: duplicate the track or clip first for an easy way back.)

• Off-tempo clips. If a clip was recorded at a different tempo than your Set, Live's warp markers can sit a few milliseconds off the real transients, so timing may not be perfectly tight. Beat Inspector warns you when it finds off-tempo clips in the selection. For the tightest result, consolidate those clips and re-insert warp markers (which re-bakes them to the Set tempo), then re-run. Clips recorded at the Set tempo are sample-accurate.

• Processing can be slow. Analyzing and rebuilding a large selection — many clips, or several tracks at once — can take a while. The current Extensions SDK beta makes the heavy steps run one at a time (each clip is rendered and analyzed in turn, and the slices are written sequentially because creating them in parallel can drop clips), so time scales with the total number of clips and slices. A tighter selection is faster.

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Feedback

This is an early release — bug reports and feature requests are very welcome. Please include your Live version, what you selected, and (if relevant) a screenshot of the clip and its warp markers.