Use AURoundtripAAC to check audio files for clipping on Mac
The AURoundtripAAC Audio Unit lets you compare audio encoded using iTunes Plus AAC against a source audio file. It also includes clip and peak detection, as well as a simple listening test environment. You can use the audio unit in any audio unit host app, such as Logic Pro X or GarageBand.
Click Listening Test to perform a double-blind test to identify an “unknown” audio source as either source audio or encoded audio.
The AURoundtripAAC Listening Test window has three buttons: Source, A, and B. The Source button always auditions the source audio. At the beginning of each test cycle, the source audio is randomly assigned to either the A or B button, and the encoded audio is assigned to the other button.
Click Training Mode to display the results of the test each time you select a source. This mode should be used for training only. For reliable ABX testing, run a predetermined number of test cycles before viewing the results.