Clarinet “undertones” or “grunts” are the unpleasant low sounds that happen usually at the beginning of tongued upper-clarion-register notes (about written G to C, above the staff). They are the lower register speaking out of turn—a clarion G’s undertone, for example, is the chalumeau C.
Fine clarinetists can more or less eradicate the problem, but there isn’t a lot of consensus or clarity among clarinetists about how exactly this is done. I checked some published clarinet wisdom that I had at hand, to see what some of the experts say about what causes undertones, or how to eliminate them. Here are the results:
This listing isn’t comprehensive, so I welcome submissions if you can point me toward published sources. And in many cases I have done some interpreting of the authors’ intents. (Julie DeRoche, for example, lists a number of embouchure specifics in her article, which I have reduced to “Ensure correct, stable embouchure formation.”) If you are one of the authors, or have particular insight into their thinking, I also welcome corrections.
I’m refraining from comment or conclusion at this point, but stay tuned for a future post.