Source : Webster's Revised Unabridged Dictionary (1913)

Voice \Voice\, v. t. [imp. & p. p. {Voiced}; p. pr. & vb. n.
   {Voicing}.]
   1. To give utterance or expression to; to utter; to publish;
      to announce; to divulge; as, to voice the sentiments of
      the nation. ``Rather assume thy right in silence and . . .
      then voice it with claims and challenges.'' --Bacon.

            It was voiced that the king purposed to put to death
            Edward Plantagenet.                   --Bacon.

   2. (Phon.) To utter with sonant or vocal tone; to pronounce
      with a narrowed glottis and rapid vibrations of the vocal
      cords; to speak above a whisper.

   3. To fit for producing the proper sounds; to regulate the
      tone of; as, to voice the pipes of an organ.

   4. To vote; to elect; to appoint. [Obs.] --Shak.

Source : WordNet®

voicing
     n : the act of adjusting an organ pipe (or wind instrument) so
         that it conforms to the standards of tone and pitch and
         color