There are many variations in sound quality you can make simply by altering the shape of your vocal “tube” or tract.
Your tube is the length and area where your breath passes as it blows through your vocal cords. Moving the “house” or “voice box” gives you many options. Knowing how to move it up or down will instantly change the sound of your voice. When your voice box (larynx) is lower in your throat, you have lengthened your tube creating a darker, more robust sound. Move your larynx up, and you have shortened your tube to create a thinner more piercing sound. The entire voice box can tilt as well.
The tongue, soft palate, and shape of the mouth will give you many vocal colors to play with. When the soft palate is low for instance, the breath may escape through the nose changing the sound. If the tongue is high there is added resistance to the breath creating a pressure change which is essential for the “belt” sound.
These are just a few options that can add texture and interest to your voice.