The Collaborative International Dictionary of English v.0.48:

Shrill \Shrill\, v. i. [imp. & p. p. Shrilled; p. pr. & vb. n.
   Shrilling.] [OE. schrillen, akin to G. schrillen; cf. AS.
   scralletan to resound loudly, Icel. skr["o]lta to jolt, Sw.
   skr[aum]lla to shrill, Norw. skryla, skr?la. Cf. Skirl.]
   To utter an acute, piercing sound; to sound with a sharp,
   shrill tone; to become shrill.
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         Break we our pipes, that shrilledloud as lark.
                                                  --Spenser.
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         No sounds were heard but of the shrilling cock.
                                                  --Goldsmith.
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         His voice shrilled with passion.         --L. Wallace.
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WordNet (r) 3.0 (2006):

shrilling
    n 1: a continuing shrill noise; "the clash of swords and the
         shrilling of trumpets"--P. J. Searles