How can I stop my pitch from quavering and wavering and being unsteady when I si

Question:

How can I stop my pitch from quavering and wavering and being unsteady when I sing a long held note?

When I sing a long note, my pitch slightly wavers throughout the note. It is like a vibrato, except that it is a random pitch variation, not even or periodic, and not as much pitch variation as a vibrato. The overtones are especially susceptable to this, and the brighter I make a note, the more obvious is the effect. Also, it is not controllable by me. It seems to be worse for low notes. I could use specific advice as to how to train to end this problem, as right now it makes me sound as though I am off pitch. I would like a steady, pure sound.

Additional Details

8 months ago
If I try to use "support", by tightening various trunk muscles (but what are the "intercostal muscles?"), it seems to work for about 30 seconds, and then I get a more vibrato-like variation in pitch, but at a high rate. Is this my crico-lyrngal muscle acting up? Any further help would be appreciated.

Best Answer - Chosen by Asker: 8 months ago
If I try to use "support", by tightening various trunk muscles (but what are the "intercostal muscles?"), it seems to work for about 30 seconds, and then I get a more vibrato-like variation in pitch, but at a high rate. Is this my crico-lyrngal muscle acting up? Any further help would be appreciated.