How to make terminal bell not so loud (quieter)?

I use Debian and Mate, also I use vim a lot. There are a lot of answers about how to disable that loud beeping sound, it is called "terminal bell" in mate-terminal settings, but actually the sound alert has some good use in vim. My typical workflow is to work with a silent music and I need the alert to be quieter. It sounds like a drip of water and not like system beep. An example of possible solution: if I figure up where the sound file is located, I would like to edit it with an audio editor.