General Tone:
* Mood
* Atmosphere
* Style
* Character
* Manner
* Voice
Specific Tone:
* Formal/Informal
* Serious/Humorous
* Optimistic/Pessimistic
* Aggressive/Passive
* Neutral/Subjective
* Sarcastic/Sincere
* Condescending/Respectful
For Writing:
* Register
* Diction
* Syntax
For Music:
* Pitch
* Timbre
To give you the most accurate synonym, please provide me with the context in which you want to use "tone."