You can, but you'll need a special software program to do so. The good news is that you have plenty of free software (also called "freeware") options from which to choose. There are commercial options, as well, but depending on your need (what sort of volume and quality conversion you're looking for), these might not be worth the money. Of course, with freeware, you might also be getting what you pay for. So when you're deciding whether you want to go with freeware or a purchase, think about all your needs.
If you do decide to explore your freeware video editing options, you want to keep in mind a few other issues. First, don't expect the same kind of customer support, if any at all, from a freeware supplier. You can minimize this issue by checking out how often the author or developer of the freeware updates the product and what kind of support materials you get with your download. Also read through the user reviews of the freeware, both from the casual user and from real techies, as well. Lastly, make sure that the freeware provides you with a General Public License (GNU), so you know you can use it for free.
Regardless of whether you go the freeware or commercial route, make sure you consider whether the packages you're looking at will change all the various audio formats you might want to work with; mp3 and wav are just two of a long list of audio file types. If you're going to do a lot of converting, make sure your selection offers a batch conversion process. Some converters strip the files of their ID3 tag, so if keeping the tag is important to you, make sure you use a package that keeps it intact. Also, not all programs work on all operating systems; plus, you need to make sure you have the processing power on your computer to handle the program. There are also a range of features, such as volume control, compression, and bit rate, to name just a few. Do your homework so you understand what options are out there and which ones you'll want to use.