In the previous post, I talked about the trill and how it is a revolutionary vocal exercise because it effectively takes the strain off of the vocal chords, so you can not just use them as a warm up exercise, but you can use it to extend the range and sing higher notes. The revolutionary part of the trill is that while most singers feel strain in their higher range, since the trill takes the weight off of the voice, you can work and stretch that higher range without the tension!
Okay, so let’s talk some more about how to do the tongue trill and what sound should be made under it to lessen the vocal strain even more. So, the fingers are pressing in the cheeks to where you can feel the teeth. This lifts the weight of the skin, and the lips are closed, as you blow the rapid series of /b/.
The sound under the trill should be a low, dopey “uh” sound. It shouldn’t be a squeezy, whiney “eh” sound. This will keep the larynx low and prevent it from rising too much as your notes get higher.
This same thing can be done with the tongue trill. This differs from the tongue trill in that the tongue bats up against the roof of the mouth, similar to the formation and sound of the rolled /r/ in Latin American speak. All the other guidelines of the lip trill apply to the tongue trill.
Hope this is helpful!