When the QuickTime GUI is presented in a web browser page, one can get extra loud audio volume by shift-clicking the volume control. Is there similarly a way to coax a louder-than-normal audio level in the QuickTime Player app?
Click "Show Movie Properties" in the "Windows" menu (⌘J). Click the "Audio Settings" tab and move the "Volume" slider to the right. If you need more, select the "Sound Track" and move its slider. You can save the file, so it will play at high volume next time.
Click "Show Movie Properties" in the "Windows" menu (⌘J). Click the "Audio Settings" tab and move the "Volume" slider to the right. If you need more, select the "Sound Track" and move its slider. You can save the file, so it will play at high volume next time.
A big thanks and tip o' the hat to Malcolm Rayfield for a concise and complete solution. With both volume sliders I can get 12 dB extra gain. On my particular videos in question, their dreadfully inadequate audio levels don't clip & distort when raised, but rather become listenable. The accompanying boosted noise floor is a small price to pay for salvaging my formerly useless videos, and since it is speech, a tweek downward in the treble helps.