So I've spent the last couple days working with the TC Helicon C1 vocal pedal, and I thought I would share my review of it to anyone interested. I've noticed that there hasn't been a lot mentioned about the C1 on the internet, so I hope this helps.
I bought the C1 for $140 on ebay and I think that's about as cheap as you're going to find it. I was really reluctant to buy it because of the lack of reviews on the internet but I thought I would take a chance.
The C1 is very easy to operate. There's only three knobs controlling: Key, Tuning, and Gender.
KEY: If the singer plays guitar, I suggest using the CH (chromatic) key setting because the pedal will track your chords, so you wont have to adjust the pedal for every song.
(Place the pedal first in your effects chain because it requires a clean signal)
GENDER: When it comes to the gender knob, you can get some pretty wacky effects from deep monster like voice to a high pitched alien voice. If for whatever reason you would need it, you got it. I keep the gender knob at 12o'clock so it's not doing anything to my signal.
TUNING: As far as tuning, if you are after that T-pain effect, this is your pedal. The tuning knob is very sensitive, I have it just before the off position to smooth out my notes/bad notes, anything after that, you start to hear a hard tuning effect.
Overall, I give it a 9 out of 10 because of it's durability, xlr in/out, gain knob, and capabilities. I just wish it wasn't so sensitive.