Distorting tenor notes
Hi guys. On some days it seems that I can only put distortion/rasp on notes in the E4-C5 range (or thereabout) by simply INCREASING VOLUME until the sound starts to distort. It's pure guttoral screaming and doesn't feel that great in my throat. But on other - better days, I can bring out the rasp simply by thinking more "aggressive" - the sound will be fairly loud, but I still feel that I can get a bit louder. But on those "bad" days, it strains my voice to sing high notes with rasp, I feel that I'm at my maximum volume limit and I really get tired.
I've SOMEWHAT figured out what the problem is, but I'd like to hear your opinions. So my question is:
When I can only distort tenor notes by simply increasing volume and pulling chest TOO high up in pitch, what could I be doing wrong?
Thanks in advance!