Audio levels

I realized after listening to the talking at different levels, its obviously  harder to hear. The first one was balanced, clear audio you could hear well. The second one was too loud, the sound was distorted and could not hear, and was hard to hear. The 3rd and final one was recorded too quietly which was very hard to understand because you could not hear anything. I learned that the higer the frequency the higher it will sound, the lower the frequency the lower it will sound. To fix loud audio or low audio all you have to do is adjust the sound frequency in sound option or settings in a program.