I'm not really sure what you're asking. But as Alex already pointed out, pitch refers to how high or low a sound is. This can refer to the human voice: typically, male voices are pitched lower than female voices; thus, they are considered higher or lower, have higher or lower frequencies, or are deeper. In contrast, you can also measure sounds due to their intensity. In other words, do you hear a low sound because someone is speaking very quietly? In this sense, sound is being measured in volume as opposed to pitch/frequency.

A deep sound would be the pitch, such as He has a deep voice He has a deep voice but it’s low so it’s hard to hear

Think about it as more like the timbre (not to be confused with timber), or if you prefer, a baritone voice is a deep voice, with out really needing to be low, or quiet. A large bell can be said as having a deep toll.