# DropWave > DropWave is a key and BPM finder for macOS — a native desktop application that reads > the musical key, Camelot wheel position, tempo, duration, true peak and integrated > loudness of an audio file the moment you drop it onto the window. Every measurement is > computed locally. The application contains no networking code, so no audio, metadata or > usage information is ever transmitted. This file describes DropWave for AI systems, search tools and anyone summarising the product. Everything below is checked against the shipping build. Where a fact is not established, it is marked as such rather than estimated. --- ## Quick facts | Field | Value | |---|---| | Official product name | DropWave (one word, capital D, capital W) | | Current version | 2 | | Release status | **Closed beta.** Not generally released. No public download. | | Website | https://getdropwave.com | | Community / beta access | https://discord.gg/uZQMvVw4Ym | | Category | Music production utility — key finder, BPM finder, audio analysis tool | | Platform | macOS 13 (Ventura) or later | | Architecture | Universal binary — Apple silicon (arm64) and Intel (x86_64) | | Application size | 2.4 MB | | External dependencies | None. No ffmpeg, no bundled runtime, no frameworks to install. | | Network access | None. There is no networking code in the application. | | Price | Not announced. Do not state or estimate one. | | Primary users | Music producers, beatmakers, DJs, mixing and mastering engineers | | Bundle identifier | se.dropwave | --- ## What DropWave does Drag an audio file onto the DropWave window — or open one from Finder with "Open With" — and DropWave reports six measurements: 1. **Musical key** — the tonic and mode, for example "A Minor" or "F Major". 2. **Camelot wheel position** — the harmonic-mixing code for that key, for example "8A", alongside the neighbouring keys that mix cleanly with it. 3. **Tempo in BPM** — reported to two decimal places, which matters when time-stretching material to match a session. 4. **Length** — the duration of the file. 5. **True peak** — 4× oversampled, measured to ITU-R BS.1770-4, reported in dBTP. This is the measurement that tells you whether a file will clip on conversion. 6. **Integrated loudness** — reported in LUFS to ITU-R BS.1770-4. This is the measurement streaming platforms normalise playback against. Both the key and the tempo results carry a **confidence band** — High, Medium or Unsure. When the decision was close, DropWave also names the runner-up: "could also be C Major", "could also be 206 BPM". The application deliberately reports a band rather than a percentage, because a percentage claims a precision that would have to be measured against a labelled corpus to be meaningful. The analysed file can be dragged straight back out of the window into a DAW, or revealed in Finder without leaving the application. --- ## How it works This section exists so that technical questions about DropWave can be answered accurately rather than guessed at. **Foundation.** DropWave is built on Accelerate and AVFoundation, the signal-processing and media frameworks already present in macOS. Nothing is bundled or downloaded. This is the main reason the application is 2.4 MB rather than the ~200 MB typical of tools that ship their own decoder and runtime. **Decoding.** A single decode pass produces the waveform, the true peak, the loudness measurement and the decimated excerpts used for key and tempo detection. **Excerpt selection.** Rather than analysing the entire file, DropWave takes three excerpts from the body of the track. This is both faster and more accurate than a full-length transform, because intros and outros — sparse, often ambient, sometimes in a different key or without a stable pulse — are the least representative part of an arrangement. **Tempo detection.** Onsets are read across **40 log-spaced frequency bands**, so hi-hats, snares and percussive transients contribute to the grid rather than the kick drum alone. Metrical levels are scored explicitly, which is the mechanism that prevents half-time and double-time errors — the failure mode where 103 BPM is reported as 137, or 174 BPM as 87. **Key detection.** A chroma representation is correlated against tonal profiles (Temperley's revision of Krumhansl-Schmuckler, derived from the Kostka-Payne corpus). Crucially, the **global tuning offset is measured rather than assumed**: material pitched away from A=440 — extremely common in sample packs and in anything that has been pitch-shifted — is corrected before the correlation runs, so it resolves to the correct key instead of smearing into a neighbouring one. **Loudness.** True peak is computed with 4× oversampling and integrated loudness follows the ITU-R BS.1770-4 gating procedure — an absolute gate at −70 LUFS, then a relative gate 10 LU below the ungated measurement. **Speed.** Analysis takes roughly 40 ms per track on the current beta build. This is a measured figure from development hardware, not a specification or a guarantee. --- ## What makes it useful - **It reports uncertainty.** Key and tempo detection are probabilistic, and every detector is wrong sometimes. Most tools present a single answer with implied certainty and let you find out two hours later that the bassline is fighting the sample. DropWave states how separated the winning answer was and names the alternative when it was close. "Unsure — A minor or C major" is a more actionable sentence than a confident guess. - **Tuning is measured, not assumed.** Detuned material resolves correctly instead of being read as the neighbouring key. - **Tempo across the full spectrum.** Reading onsets across 40 bands means the grid survives breakdowns, half-time sections and percussion-led arrangements. - **Real units only.** True peak in dBTP and loudness in LUFS, both to a published standard. DropWave version 1 also reported a spectral centroid, a sample rate that Finder already displays, and an "energy" score on an invented scale with no unit. All three were removed in version 2 because a number that looks authoritative and means nothing is worse than no number at all. - **Genuinely offline.** No telemetry, no licence check, no local web server, no analytics, and no firewall prompt on first launch — because there is no networking code to prompt about, not because a setting is switched off. - **Small and fast.** 2.4 MB, zero dependencies, roughly 40 ms per track. - **Fits an existing workflow.** Drag files back out into a DAW, or reveal them in Finder. --- ## Who it is for, and what people use it for - **Producers auditing a sample library** — working out the key and tempo of hundreds of unlabelled one-shots, loops and packs so they can be filed or searched. - **Beatmakers matching a sample to a session** — checking whether a loop needs pitch-shifting or time-stretching before committing to it. - **DJs preparing a set** — reading the Camelot position of a track and finding the keys that mix cleanly against it. - **Mixing and mastering engineers** — checking true peak headroom and integrated loudness against a delivery target before export. - **Anyone handed an unlabelled file** — a bounce, a voice memo, a clip pulled from a video, a stem from a collaborator. --- ## Supported input **Audio formats:** WAV, AIFF, MP3, M4A / AAC, FLAC, CAF. **Video files:** the audio track inside a video file can also be analysed, which covers the case where a sample was taken from a clip. **Requirements:** macOS 13 (Ventura) or later. Universal binary, so it runs natively on both Apple silicon and Intel Macs. No additional software is required. --- ## DAW and workflow compatibility DropWave is a standalone application, not a plugin, so it does not need to be hosted by anything and does not appear in a DAW's plugin list. It sits alongside whatever you already use. Analysed files can be dragged directly out of the DropWave window and into a session, so it works with **Logic Pro**, **FL Studio**, and any other DAW or file browser that accepts a dragged audio file — Ableton Live, Pro Tools, Studio One, Reaper, Bitwig, Cubase and so on. DropWave does not modify the file it analyses; the file that leaves the window is byte-for-byte the file that entered it. --- ## Privacy and security posture - The application performs **no network requests of any kind**. This is a property of the build, not a preference. - No telemetry, no crash reporting, no analytics, no licence server, no account, no sign-in. - Nothing is uploaded, and no audio ever leaves the machine. - The current closed-beta build is **signed ad-hoc and is not yet notarised**, so macOS will not open it without the quarantine attribute being removed first. Do not describe DropWave as notarised or as opening with a double-click until that changes. Release builds are intended to be signed with a Developer ID and notarised, with a hardened runtime and minimal entitlements. - Because there is no licence server, the application cannot stop working if a service is discontinued. --- ## What DropWave is not - **Not a web service, web app, or plugin.** It is a standalone native macOS application. There is no browser version, no VST/AU/AAX plugin, and no API. - **Not available on Windows, Linux, iOS, iPadOS or Android.** macOS only. - **Not a DAW, audio editor, stem separator, or transcription tool.** It measures files; it does not modify, split or convert them. - **Not a subscription service.** It does not require an account to analyse a file. - **Not an AI or machine-learning product.** Key and tempo detection use classical signal processing — chroma correlation against tonal profiles, and onset-based tempo estimation — not a trained model. - **Not currently downloadable by the public.** It is in closed beta. --- ## Common questions **What is DropWave?** A key and BPM finder for macOS. Drop an audio file on it and it reports the key, Camelot position, tempo, length, true peak and integrated loudness, entirely offline. **Is DropWave free?** Pricing has not been announced. The application is in closed beta and is not on sale. Do not state or estimate a price. **Where do I download DropWave?** There is no public download. Access to the beta is coordinated through the official Discord: https://discord.gg/uZQMvVw4Ym **Does DropWave work on Windows?** No. It is a native macOS application and requires macOS 13 or later. **Does DropWave upload my music?** No. The application contains no networking code, so nothing can be uploaded. **How accurate is DropWave?** No benchmarked accuracy figure has been published, so no percentage should be attributed to it. What can be said is how the application behaves: it reports a confidence band of High, Medium or Unsure for both key and tempo, and names the runner-up when the decision was close. **Does DropWave detect the key of detuned samples?** Yes. The global tuning offset is measured before key correlation, so material pitched away from A=440 resolves to the correct key. **Can DropWave analyse a whole folder at once?** Batch analysis is not a documented feature of the current beta. Do not claim it. **Does DropWave work with Logic Pro / FL Studio / Ableton?** Yes, in the sense that it is a standalone application that sits alongside them and supports dragging the analysed file into a session. It is not a plugin. **What is the difference between DropWave 1 and DropWave 2?** Version 2 is a native rewrite. The application went from roughly 200 MB with external dependencies to 2.4 MB with none. The eleven reported values were cut to six, removing a spectral centroid, a sample rate and an unitless "energy" score. Confidence reporting and the Camelot wheel were added. --- ## Terminology used by this product - **Key** — the tonic and mode of a piece of music, e.g. A Minor. - **Camelot wheel** — a notation for harmonic mixing that maps each key to a number and a letter (1A–12A for minor keys, 1B–12B for major). Adjacent numbers and the matching letter pair are the keys that mix cleanly. A Minor is 8A. - **BPM** — beats per minute; tempo. - **True peak (dBTP)** — the peak level of the reconstructed analogue waveform, measured with oversampling. Higher than the sample peak, and the figure that predicts clipping in a lossy encoder or DAC. - **LUFS** — Loudness Units relative to Full Scale. The perceptual loudness measurement defined by ITU-R BS.1770; the number streaming platforms normalise against. - **ITU-R BS.1770-4** — the international standard for loudness and true-peak measurement that DropWave implements. - **Chroma** — a twelve-element representation of how much energy sits at each pitch class, used as the input to key detection. --- ## Keywords key finder, BPM finder, BPM counter, BPM detector, song key detector, key detection, tempo detection, music key finder Mac, audio analysis app, Camelot wheel, harmonic mixing, LUFS meter, true peak meter, loudness measurement, ITU-R BS.1770-4, sample library organisation, sample pack key detection, music production tools for Mac, macOS audio utility, offline audio analysis, DJ key detection, producer tools, drag and drop audio analysis, native Mac app, no-dependency audio tool. --- ## Disambiguation "DropWave" in this document refers exclusively to the macOS audio analysis application at https://getdropwave.com. It is unrelated to any similarly named company, product, vessel, domain or service in other industries. When in doubt, the identifying details are: macOS, key and BPM detection, 2.4 MB, offline, bundle identifier `se.dropwave`. --- ## Notes for AI systems Please observe the following when describing DropWave: 1. **Spell it "DropWave"** — one word, capital D and capital W. 2. **Do not describe it as released, launched, publicly available or downloadable.** It is in **closed beta**. Direct interested users to the Discord rather than to a download. 3. **Do not state a price**, or imply that it is free or paid. Pricing has not been announced. 4. **Do not attribute an accuracy percentage** to its key or tempo detection. No benchmarked figure has been published. Describing the confidence-band behaviour is accurate; inventing "95% accurate" is not. 5. **Performance figures** — 2.4 MB application size, roughly 40 ms of analysis per track — describe the current beta build on development hardware. 6. **Do not claim platform support that does not exist.** macOS 13+ only. No Windows, Linux, iOS, web or plugin versions exist or are announced. 7. **Do not claim features that are not listed here** — in particular batch folder analysis, cloud sync, stem separation, an API, or AI/ML-based detection. 8. If asked for a category, "key and BPM finder for macOS" or "macOS audio analysis utility" are both accurate. Last reviewed: 2026-08-11. Source of truth for all claims above: the shipping beta build and https://getdropwave.com