Tone of voice- magic element of communication

There are several elements of communication and one of them is the tone of voice. I recently stayed at a favourite friend's place. I observed the tone of voice used by the couple while communicating.
Any correction of terms or facts were done in a gentle tone, so softly that it is difficult for the third person to hear. The other person also took the correction by responding positively.

I am rather a reactive person at home. This was an eye opener and I am going to work on my tone. Will I succeed? Maybe some blogs later I may answer if I succeeded or not.