Attacking is hard, firm, loud.
Friend is soft, gentle, quiet, yielding.
A friendly voice:
Quiet so speak the lowest can, but still easily heard.
Each note and tone starts and ends softly, so does not suddenly start, volume increases and decreases slowly.
High pitch as this has a shorter wavelength so is softer.
An attacking voice
Loud, this really forces the voice on the person, it is forcing yourself on the person, they have to conform. It is also painful as so loud.
Each note and tone starts and ends sharply, so does suddenly starts, volume increases and decreases fast. This makes each note harsher and harder.
Low pitch as this has a longer wavelength so is harder.
General:
People will be attracted by a soft voice and be repelled with a harsh one.
These of course need to be done with other factors, such as a man still needs to sound masculine etc.
Lifetime Wisdom 