Jamman,
Can you kindly write a comparison for VH quality of your Korg’s TC and Digitech Vocalist VR
Sure thing. The Digitech VR was what I used when recording "A nightingale sang..." about 30 years ago. It was easy to use, followed my "scoops" well, and was surprisingly convincing when used tastefully.
The Ketron X1 had a very useable harmonizer, as you can hear in "She's no lady". That was a close second to the TC in my book.
The TC unit in the PA900 was featured on "The Prayer", and it is a simple 1 above harmony that tracked very well, and sounded cleaner to me than the VR.
The unit in the PA4x is even more powerful, and has more voices available.
In my guitar/trax rig I use a TC Voive-Live 3, and that is the best of them all. Perfect tracking, total control, and almost unlimited effects possibilities.
I find that harmonies sound best when separated (L&R) with the lead in the center. By "best" I mean they have more of a locational effect that adds to the realism.