I don't know whether the TC Helicon Electric is still available; but that is the vocal effects box which I use anytime I use one. It has reverb and delay, it also has pitch correction, which I have used sparingly when I have recorded. It also has some neat "harmonizer" capability so that you can play a guitar into it, sing, and the unit will generate one or two more vocal parts, depending on the settings you enter. You can also adjust the relationship between the note you sing and the note or notes you get. Thus, if you wanted to emulate bluegrass harmony, you can set for "high," and "higher" to do a pretty good job of doing up a bluegrass song, at least on the simpler chord patterns. It also can use a footswitch to cycle through the memories up or down. It takes a bit of "doing" to get it set the way you want; but I have been happy with my unit. It also came rom Sweetwater, and I have enjoyed dealing with that company very much
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