Loud and Clear is a free web app and VST3/AU plugin that shows an audio file's peak, LUFS, and RMS values over time. The main point of the plugin is to be able to quickly set the gain to the loudest level it can be before clipping.
Drop in a file and click Match Target and Gain is automatically set so the file's maximum true peak is −0.1 dBTP (by default), which is as loud as the file can safely be without limiting or clipping.
Export saves a 24-bit WAV at the original sample rate with only that gain applied.
Unlike a file's sample peak values, which are the level of each sample, true peak is the level of the curve the converter draws between the samples. That curve can rise higher than the samples on either side of it by an amount that can be calculated. So a file that reads 0 dBFS on a sample meter can still clip the output.
Loud and Clear measures true peak using the ITU-R BS.17701 method of resampling the file four times over and taking the largest value.
LUFS is perceived loudness: the signal weighted the way the ear hears and averaged over time, integrated over the whole file with BS.1770's gating, as EBU R 1282 uses it.
RMS is the plain average level with no weighting, in accordance with AES174. At 300 ms (the default) it responds similarly to a VU meter.
Right-click a button to choose from the following:
Peak: True, 5 ms, or 10 ms
LUFS: 400 ms, 3 s, or Integrated (the whole file)
RMS: 50 ms, 300 ms, or Integrated (the whole file)
Use the web version or download the plugin. Everything happens in your browser: the file never leaves your computer.
Learn more about each control by hovering over it, and turn off this feature in the main menu at any time.
1. Recommendation ITU-R BS.1770, ITU. 2. EBU R 128 and Tech 3341, European Broadcasting Union. 3. IEC 60268-10, Peak programme level meters. 4. AES17, Measurement of digital audio equipment, Audio Engineering Society.