What vocal exercises can one do to deepen his voice?
First, remember that not all voices are designed to be deep. This is why there are tenor, baritone and bass singers in the chorus. As someone who uses their voice to make their living, I can suggest some things you can do to improve the lower register of your voice. I suggest reading or reciting aloud, speaking clearly but not loudly. As you do, place a hand on your chest, and see if you can feel it vibrating. If so, you are resonating in your chest, which should give you a rich, natural tone. You may also try singing a glissando–kind of like a musical slide down. Do it repeatedly (best done alone, so others won’t think you’ve lost your mind!), again feeling for the vibration in the chest. If you’re resonating properly, you’ll feel the vibrations strongest at the lowest part of the gliss. These are by no means definitive, nor should they be interpreted as coming from a professional voice teacher. These are tools I have used throughout my career to help me, and I hope they are of help
