Hey guys!
quick question..

Im a Tenor, but I simply LOVE singing in C# tuning. (Semitown down from DGCFAD) It fits my voice in so many songs. If I keep singing in that tuning, even though its low, will my range increase and overall singing voice still improve? I guess so right?
Tuning doesn't really necessarily dictate what keys you sing in. Generally speaking, certain keys are easier to play on a guitar due to to open strings (C, G, E, A, D), but that doesn't mean that you can't play in other keys. Plus the existence of capos negates this and allows you to play open position chords easily in any key.

But without a capo, the same relative keys, all shifted three semitones down, will be very easy. So that would be A, E, C#, F#, and B. But again, capos make any key easy and if you can get by without open chords, you can play in any key in any tuning to an extent.

Also depending on your range, you may be able to sing in the same key either in a higher or lower octave and in some cases you can easily sing the same song in the same key in more than one different octave, especially if the song only has a small range.

Trying to sing higher or lower won't really extend your range though since range is determined by the makeup of your vocal chords, and those can't really be changed without maybe surgery, aging, or some serious testosterone injections (such as what FtM transsexuals go through during HRT), and those really aren't viable options.

With good training it will be easier to hit the notes at the extremes of your range with better accuracy and tone, even with good training you probably won't be able to increase your actual range by more than a couple of semitones, if that.

Struggling to hit notes outside of your range, especially if you are not being properly trained, is very bad for you and will probably not help you.
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