Basically when you use "/playsound block.wood.hit master @a ~ ~ ~ 1 1" It plays the exact same sound as if you use "/playsound block.wood.step master @a ~ ~ ~ 1 1". They both play the "step" sound. The same is if you change the "wood" with stone. I've only tested wood and stone but as far as I know they both play the "step" sound for that block type.