Is that from a PSR-E463? If it is, which voice number did you use?
Edit: I know you said "PSR-4600" in your post, but the filename says "463," which is why I'm asking. If it's from a PSR-E463, there might be acsimilar voice on the PSR-EW400 that I could look at. But if it's from a PSR-4600, I'm not sure what technological differences there might be in the sound-generating methods used between that old model and newer models.