Screenshot:
A Web Extension that inserts a Web Audio API GainNode and DynamicsCompressor
node to increase the audio level of videos that are too quiet, while limiting
the maximum volume of those videos.
This is an enhanced version of https://github.com/padenot/up-to-eleven: the input gain for the gain section, and the threshold and ratio for the compressor are now controlled by sliders in a pop up window.
There is an enable/disable button in the pop up window that allows you to turn the extension on and off.
There is a VU meter to see the audio levels.
The Gain controls amount of gain applied before the compressor You can set this to 1 and there will essentially be no effect.
The Threshold determnines the volume levels above which the compressor will affect. All the way to the right and the compressor will do nothing. All the way to the left and the compressor will force all audio to the same volume(or try to). Somewhere about -20 is a good place to start.
Ratio is how much the compressor "compresses" the audio. To make everything the same volume, increase the ratio above 10. For a subtle effect, set the ratio to a low setting like 2 or 3.
Go to the link below and add the extension to your browser.