PER

PER is a free blind listening test application for Mac and Windows, made for comparing mixes, masters, and other audio versions quickly and fairly.

The idea is simple: load a few audio files, choose a LUFS target, and start listening. PER analyzes and normalizes the files before the test begins, then hides the file identities so you can compare the versions without knowing which one is playing.

PER is designed to make blind listening tests fast enough that they actually get done. There are other ways to set up blind comparisons, but they often involve building a DAW session, hiding tracks, renaming files, routing things around, or trying to trick yourself into not knowing what you are hearing. PER keeps the workflow focused:

• Load the files.
• Choose a LUFS target.
• Listen and rate.

During the test, you only see the listening buttons. No filenames. No visible file identity. No "this one is louder, so it must be better".

After each listen, you rate the version from 1 to 6. When the selected number of ratings per file has been completed, PER shows a ranked result with average scores and the original LUFS-I values, so you can see both what you preferred and how loud the original files were before normalization.

PER can be used for:

• Comparing different masters of the same song.
• Comparing different mixes.
• Letting band members vote on different versions independently.
• Checking whether the louder version is actually preferred.
• Testing processing chains without knowing which one is which.
• Making mix and mastering decisions with less visual and emotional bias.

PER also includes a project export function. This makes it possible to send the same blind listening test to someone else, for example a band member, producer, artist, or client, so several people can compare the same mixes or masters independently.

Important note: exported PER projects include the audio files. Only share exported projects if you have the right to share the audio, and only send them to people you trust.

Main features

• Blind comparison of multiple audio files.
• LUFS-based normalization before listening.
• User-selectable LUFS target.
• Rating system from 1 to 6.
• Ranked result after the test.
• Original LUFS-I values shown in the result.
• Optional rating normalization for fairer results.
• Rating normalization can be turned off in Settings.
• No fixed 8-file limit.
• Option to convert files to the same sample rate or keep the original sample rates.
• Project export for sharing listening tests with others.
• New button for quickly starting over.
• Confirmation step before moving to the next round.
• Available for Windows, Apple Silicon Mac, and Intel Mac.

Video

This video shows the first version of PER. A few more features have been added since the video was made, but it still shows the basic idea and workflow:

{See video at top of page}

Availability & Pricing

PER is free, but it requires that you follow Noisebud's Patreon campaign. You do not need to be a paying member to use it.

When you start PER, you enter your email address in the application. PER then checks whether that email is connected to a Patreon account following Noisebud. If you stop following the campaign, PER will eventually stop working.

More info and download:
https://www.patreon.com/posts/160240913