Getting started
From a file on your desk to a verdict per platform in ten seconds — and what each part of the panel shows.
On this page
Quick start
- Open LoudSense from the dashboard.
- Drop a WAV, MP3, AAC, FLAC or OGG onto the drop zone, or click Choose files or Choose a folder. Up to 1 GB per file, up to a hundred files at once.
- Watch the progress bar. WAV and MP3 stream through in chunks; a 20-minute episode takes a few seconds on a laptop.
- Read the panel: waveform, marks, curve, and the stats row.
- Pick a target group — Podcast, Music streaming, Broadcast or Live — and read the verdict rows. Each one says OK, too loud, too quiet or peaks too hot, and what to change.
- Copy report puts the numbers and verdicts on the clipboard as text, ready for a message to the client or the band.
The panel
- Waveform — the whole file, both channels folded into one lane.
- Red lines — clips: runs of full-scale samples. One line per run.
- Cyan marks at the top — the ten loudest peaks.
- Orange curve — momentary loudness (LUFS-M, 400 ms window) over time, mapped from −60 LUFS at the bottom to 0 at the top. It shows where an episode drifts and where the chorus lands.
- Yellow line — the playhead. Click anywhere in the waveform to seek; the transport has play, pause, stop, loop and volume.
- Time ruler underneath.
The stats row
| Stat | What it is |
|---|---|
| Peak | Highest sample, in dBFS |
| True peak | Highest inter-sample value, 4× oversampled, in dBTP |
| Clips | Number of full-scale runs |
| LUFS-M | Loudest 400 ms window |
| LUFS-S | Loudest 3 s window |
| LUFS-I | Integrated loudness of the whole file, gated |
| LRA | Loudness range in LU |
Every number is explained on Reading the numbers. The line under the row carries format, sample rate, channels, length, and two more numbers for audiobook specs: RMS and noise floor.
Health
Under the stats, LoudSense lists what it found beyond loudness: channel balance and peaks, stereo correlation (mono compatibility), DC offset, silence at the start and end, silent gaps longer than three seconds, digital dropouts (runs of exact zeros), and the clip count. A clean file gets one green line. These are the editing mistakes that reach a platform unnoticed; each finding says what to do.
Selecting a range
Drag across the waveform to select a part of the file — the intro, an ad read, the chorus. A yellow box shows loudness, peak, LRA and clips for that range alone, and Loop selection plays it round. Click anywhere to seek; Esc clears the selection; Space plays and pauses; ← → skip five seconds.
Fix it
Pick a target under the verdicts — Spotify, Apple Podcasts, EBU R128 … — choose 24- or 16-bit, and Download fixed WAV. LoudSense applies the gain the verdict asked for and, when the raised peaks would cross the target's ceiling, a true-peak limiter at that ceiling. The original is untouched; the fixed file downloads and is analysed as a new row, so you see before and after side by side. It is a normaliser, not a mastering chain: no EQ, no compression, no colour.
Encode preview
Choose a bitrate and Encode & measure: the file is encoded to MP3 in your browser and the result appears as a new row. Compare its true peak and clips with the original — that is what the encoder will do to your peaks before you upload anything. The preview is a real MP3 you can download from the list if you want it.
In Chrome and Edge the codec menu also offers AAC: the file is encoded with the browser's own AAC encoder and measured straight away. AAC previews are numbers only — no download, no playback — because the browser encodes but does not write an .m4a container.
Comparing files
Drop two or more files and a Compare table appears under the panel, one row per file, with a CSV download. The classic use: the WAV master and the MP3 you are about to upload. If the MP3 shows clips the WAV does not, the encoder added overshoot — see why the MP3 clips.
- Reference. Press ★ on a file to make it the reference; every other file then shows its delta ("2.1 LU quieter, LRA +4, true peak +0.3").
- Album. With two or more original files loaded, the album loudness appears — the number Spotify's and Apple's album normalisation act on — with the loudest and quietest track and what each service does to the whole album.
- Fix & export holds Fix it, the encode preview and the report: Export PNG saves the waveform, stats and verdicts as one image for a message to the client or the band; Copy as text does the same as text.
Speech or music?
Under the panel a thin strip marks where the file is speech (blue), music (orange) and silence, with the share of each and the loudness of just the speech and just the music. A podcast with a music bed reads one LUFS-I for the whole episode; the split tells you whether the voice itself sits where you want it, and by how much the intro jingle sticks out. The classification is a heuristic (modulation, spectral tilt, zero crossings) — treat it as a guide, not a transcript.
Episode history
Every original file you analyse is remembered in this browser — the numbers only, never the audio. When a file from the same series comes back (same name minus the episode number or date), the History tab shows a badge and a sparkline of LUFS-I over the last twelve, the spread, and a table. More than 2 LU between episodes means listeners will reach for the volume. Clear it any time; nothing is sent to the account.
A/B and "hear it normalised"
With two files loaded, the A/B tab plays them in sync and lets you flip between them. Level-matched turns the louder one down to the quieter one's loudness so you compare sound, not volume — the trick every mastering engineer uses. Hear A as applies a platform's turn-down to the current file: pick Spotify and you hear what the listener hears after normalisation. The browser can only turn down, which is exactly what normalisation does to a loud master.
Charts
The Charts tab shows a histogram of momentary loudness (a tall, narrow hill is a consistent file; two hills are a quiet and a loud part) and the short-term curve over time with the LRA band shaded and LUFS-I dashed. Download the curve as CSV gives a row per 100 ms for a spreadsheet or an editor marker list.
Folders, phones and sharing
- Choose a folder (or drop one) analyses every audio file in it — an album, a playlist, a season — up to 100 at a time, in name order. The list turns compact, the Compare table and the album loudness follow.
- On a phone with the app installed, LoudSense appears in the system share sheet: share a file from the recorder or Files and it opens analysed. The file goes from the sharing app to the page inside the device; nothing is uploaded.
- Share… sends the PNG panel through the share sheet (WhatsApp, Mail, AirDrop) where the browser supports it.
Which files work where
- WAV and MP3 stream in every current browser — memory stays flat however long the file.
- AAC, FLAC, OGG, AIFF and MP3 in older Safari decode as a whole, so they are limited to 250 MB on a laptop and 60 MB on a phone. For a long file in one of these formats, export a WAV or use Chrome or Edge.
Nothing is uploaded. If you watch the network tab while a file analyses, you will see no request carrying audio — only the page's own scripts.
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