Here you'll get information on the Harmonic Pitch Shift effect introduced to the Kemper Profiler with firmware 1.8.0 public beta.
Richard Antonelli programmed dual harmonies with the Harmonic Pitch effect. Two harmony lines played with one guitar.
When using two harmonized lines, the choice of physically playing the middle pitch is ideal: the smaller the amount of the two pitch shifts, the more natural the shifted pitches sound.
When using Intelligent harmony, I don't necessarily play the low note, and generate the harmony above. The harmony lines may sound better if the higher note is played, with a generated lower harmony.
I typically program the effect so I can play the note I consider to be the more important, and mix the harmony note to be not quite as loud. Doing that helps to mask any artificial qualities or possible glitches in the pitch shifted notes. Another bonus to this approach with pitch shifted down is that notes shifted down sound a little darker, and blend in with the un-shifted notes really well.
So, try it both ways - depending on the profile, and song, the generated note may sound better a third above, with you playing the low note, or you may like it better when you play the higher part, with pitch set to a third below.
User scales are great! I had the benefit of making a GR-55 patch awhile ago, with a virtual acoustic guitar playing a different chord inversion than the real guitar, on just some of the strings. I did it with individual + and - octave pitch shifts on various strings, so it would play in tune with whatever is played on the "real" guitar.
Q: What happens if you play a note that is outside of the scale when using the harmonic pitch?
A: DonPetersen - Let's say you're addings 3rds and set your scale to Cmaj. For C the harmonic pitch will add the major third 'E', for C# a major third 'E#' (yes, it's actually called that) and for D the scale-correct minor third 'F', which has the same pitch as E#.
C# might not be the best example since both possible thirds (minor third=E and major third E# which equals F) are in the scale of C major.
Looking at different notes answers your question better, I think (non-scale tones are italic):
A -> C (minor third, in the scale)
A# -> C# (minor third, not in the scale)
B -> D (minor third, in the scale)
F -> A (major third, in the scale)
F# -> A# (major third, not in the scale)
G -> B (major third, in the scale)}}
Also bear in mind that the Harmonizer is set up in standard tuning. If you tune down you will need to transpose the change in the harmonizer to reflect actual key.
Q: What about the harmonic minor scale? Do we need to program these in?
A: DonPetersen - Yes, that's what the user ser scales are for. you can program the more common harmonic/melodic minor scales or more 'out there' stuff like symmetrical scales.