The LH% is manifested phonetically as a dip and then a rise to a high F0 value.
It is found in anti-expectational and incredulity questions, and also in neutral questions in Valencian Catalan.
LM%
The LM% is manifested phonetically as a dip and then a rise to a mid F0 value.
It is found in obviousness statements.
Example 1: LH%
Example 2: LM%
Anti-expectational question
(Has dit) la Bàrbara?
[(Did you say) Bàrbara?]
Obviousness statement
(Sí, home,) La Bàrbara!
[Barbara (obviously)!]
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Explanations
These two examples are two similar sentences, in which the contour is nearly the same: the nuclear pitch accent is a rise (L+H*), then there is a dip on the first postaccented syllable, and finally a rise on the last syllable. The difference between these two sentences is the height of the peak at the end of last syllable: in the first one, it is much higher and the sentence is interpreted as an anti-expectational question (LH%), whereas in the second one, the peak is less high and is thus interpreted as an obviousness statement instead (LM%).