I have good ears... except while I'm singing.

[GuapitoChico]

Hi. I seem to have a problem.

I imagine a pitch in my head before I sing it. But the thing is, while I'm singing it, it sounds normal, but when played back, I hear a constant microtonal flat. A friend told me that it might be because my pitch expectations are warping my perception of what is actually coming out of my mouth. In other words, it seems that I'm hearing the expected/imagined pitch more than the actual one. Another friend told me that the "formant/timbre" of my voice is higher in my head than what is actually heard outside. My voice literally sounds deeper and lower-pitched in a recording. The higher formant might make the illusion of a slightly higher pitch than what is actually heard. Sometimes, if I'm extremely concentrated on pitch, it feels like I can hear two different pitches when I sing, but I'm sure one is in my mind and the other one is real. 

Another issue I have is that my vocal muscles are inseparably linked to my pitch imagination. Sometimes, I am aware that I'm singing slightly flat, so I try to sing a note slightly higher. The issue with that is that I cannot do that without imagining a slightly sharp note and it gets disorienting. For instance, if I were to imagine a B, my vocal muscles would lock in to a slightly flat B. I could adjust my vocal muscles to an accurate B, but my mind will automatically imagine a slightly sharp B. My friend who is vocalist told me that it's because I learned pieces by singing along to pre-existing recordings and that it's natural to unconsciously sing a tiny bit flat when doing so as not to overshadow the vocals in the reference recording. That would basically mean that this inseparable inaccurate link between vocal muscle contraction and pitch imagination is mainly due to muscle memory and I have no idea how to undo that.

I know I'm not tone deaf because I can clearly distinguish between notes, even on the microtonal level, on recordings. I can also hear microtonal sharps and flats when others are singing. I even have pretty good relative pitch. But it seems that it goes away when I'm singing in real time thanks to this psychoacoustic/psychosomatoacoustic (if such a word exists) issue.

Any tips for this frustrated fellow?

(Edit: I don't seem to have this problem when singing falsetto or within my comfort range.)

[MDEW]

   No one hears themselves the same "in their head" as they do when listening to a recording. Record yourself listen to it, note the faults, readjust and rerecord. Repeat, rinse, repeat........

   If you record using headphones, that can also "change' what you hear in your head as opposed to what is coming out of your mouth. Some people end up singing flat when using head phones. Any way the answer is to practice, record often and readjust until the ear and muscle memory are retrained.