With RealBand (or PowerTracks), the harmonizer can do it's magic over select bars, so it is granular down to the bar (if you select half a bar, it will still harmonize the whole bar, although you can cut out the stuff you don't want afterwards).

BIAB can do the whole song of part of a song. Actually, since I didn't try it, I'm not sure if it can do "multiple parts" of the song. If I get a chance, I'll try that. In which case, then yes, it can be granular to one bar (granular used to indicate the smallest unit of measure you can do).

Also, in RealBand, you can apply the harmonizer to any audio track. The same is true for BIAB, except that there is only one track, so that's the only one you can apply harmony to. If you used BIAB, you'd have to record a base audio track (maybe a male vocal), apply the harmonizer, and then bring the files into RB. Then, go back to BIAB, record another base audio track (maybe a female vocal), apply the harmonizer, and then bring the files into RB. If there were any problems, you would have to go back to BIAB to fix them. So, while doable in BIAB, it's more work; much easier directly in RealBand or PowerTracks. For that extra work, I'd spend the $49 to get PowerTracks (or $29 if you have a previous version of PowerTracks to upgrade). While TC-Helicon is not perfect, I don't think you'll find a cheaper harmonizer anywhere (other than singing or playing it yourself).

John

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