I have used the harmonizer feature to enhance vocal tracks with questionable results. I can experiment a little more and come a bit closer to what I want. However, when I try to apply the harmonizer to lead tracks, it sounds perfectly awful and I can't seem to get anything that even passes for harmony. Am I doing something wrong? Can anyone point me in the right direction?

A bit of background may help us users to help you.
1. Which TC unit are you using?
2. What input to the TC unit are you using to drive the harmonies? MIDI? Guitar? Audio? BIAB?

Jeff

I'm using the TC Helicon that comes with BIAB 2018. It is accessible in RB. I'm recording a guitar lead track first, then accessing the harmonizer to put harmony on the next track. It's all done internally in the program. I do have a stand-alone TC Helicon G that I use when performing live, but I don't think there's any way to incorporate it into RB because it is a vocal harmonizer. If I'm wrong on this, please let me know...

John, that additional info helps. I'm using a TC external VoiceLive unit also using RB. I drive the VoiceLive unit from a track in RealBand that contains the chords not the lead track.

I think it sounds like you want the TC unit to harmonize a single note lead track that you are laying down with you guitar. Is that right?

Because I have an external unit, I am not familiar with the internal TC capabilities that come with BIAB and RB, but I'm sure others here will chime in that have more experience with that.

Jeff

The internal Helicon can work in two different ways.
It can use the Chords to create the harmonies or you can create separate tracks to guide the harmony.
Been a long time since I used it, I'd have to look it up for more detail.
At one point there was a contest here using it .. there were good examples and tips in that topic.

*Edit
Found it, can't believe it's still here after all these years

Some links may not work, it's a very old post
https://www.pgmusic.com/tutorial_audioharmonies.htm

Yes, that's right. If I route the chord track from RB to the external harmonizer, how do I get the lead harmony back to RB?

Record the external harmonizer's audio output back into RB.

I've used it in the past with great results. However, starting in version 2018, I think, Helicon was only available in the 32 bit version and then stopped functioning as before. The new BB harmonizer is a hit and miss. Sometimes it's great, and often it is like you describe.
Interestingly, I was about to post that this years BB harmony is NOT working AT ALL. Very frustrating for me. Tami