307, yes single reeds can belt out some excellent sounds, a lot depends on the "stretch of the latex as that's where you can get your aggressive sounds or extremely soft sounds. Some latex's as the All Star single reed have a stretch of aprox .80 the Raging Bull single .92 the Scream N Tormentor .105 these are aprox. The larger the number the tighter the latex. Each manufacturer will dictate their desired stretch so you can see not all single reeds are created equal! The same applies for doubles & triples, each company can have different tensions on their latex where it makes them different from other companies with like layering!
Yes, lip bawls when used correctly can be a great tool. The same as a cow sound or classic location bugle. Short screams with a short lip bawl are for keeping cows together or gathering them together or pulling a stubborn one to a bull calling her to him. Powerful screams with a much growlier & deeper lip bawl & longer in tone are for pure challenges & intimidation's towards another bull. The shorter version is generally used by a bull 2-3 times inside a minute when urgently trying to maintain control or calling his herd together for possible escape or if feel threatened by another bull or predator. It's called a "round-up bugle" Hope it helps!
ElkNut1