18. The device of claim 17 , wherein operation (a) includes receiving data for one or more additional segments of the passage in a source voice, and wherein the one or more processors are configured to generate a target voice version of each of the one or more additional source voice passage segments according to x i ⁡ ( n ) ⁢ | MV = x i SRC ⁡ ( n ) - μ SRC σ SRC * σ TGT + μ TGT wherein μ SRC is a mean of all F0 values for source voice versions of segments in the codebook training material, σ SRC is a standard deviation of all F0 values for source voice versions of segments in the codebook training material, μ TGT is a mean of all F0 values for target voice versions of segments in the codebook training material, σ TGT is a standard deviation of all F0 values for target voice versions of segments in the codebook training material, x i SRC (n) is a value for F0 at time n in an F0 contour for segment i of the additional segments, and x i (n)| MV is a value for F0 at time n in an F0 contour for a target voice version of segment i of the additional segments.
19. The device of claim 18 , wherein the data for the passage segments in the source voice is generated by a text-to-speech system.