The phrase "alert ears" is correct and usable in written English.
It can be used to describe someone who is attentive and ready to listen, often in a context where being aware of surroundings or information is important.
Example: "As the meeting began, she had her alert ears on, ready to catch any important updates from the team."
Alternatives: "attentive ears" or "keen ears".
When he was born three years ago, Monarchos got to his feet with one jump, eyes alert, ears pricked, ten minutes old.
(JJ) The startled she-wolf with the pricked, alert ears is Etruscan; the two babies suckling were added in the Renaissance — or so it has long been thought.
Its head sits above a torso without arms or legs, and its cartoonish eyes stare out below alert ears embedded with speakers.
The first hint of which way the verdict was heading may have come, to some alert ears, soon after, when the judge seemed to pause to point out that "establishments known as 'strip clubs' often generate criminal activity including prostitution and narcotics".
We will never have a more alert ear, a more attractive eye, or a more ardent heart than his.
Henry Cowell's "Synchrony" well displays the composer's alert ear for layered sonorities and crunchy cluster chords.
As well as having an acute eye and an alert ear which marked his productions, Gill was an accomplished writer, too.
Gould's alert ear, startling imagination, rhythmic sparkle and ability to project contrapuntal intricacies with uncanny clarity combine impressively in these riveting performances.
Madrid's modernity is not only in its buildings, new developments, infernal traffic jams, proliferating fast food outlets, the piebald invasion of tourists, or the alert ear that can, in the queues at the Prado or at night around the Plaza Mayor, hear all the languages in the world.
Though Barbara White's "Five Elements" for piano quintet (2003) was inspired by her study of Chinese philosophy, what grabs you is her alert ear for colors and her inventive writing for the instruments, notably her use of a rectangular wood block to depress clusters of piano keys, releasing the dampers and allowing the strings to resonate when other notes are struck.
In "Seymour: An Introduction," Seymour, thinking of van Gogh, tells Buddy that the only question worth asking about a writer is "Were most of your stars out?" Writing, real writing, is done not from some seat of fussy moral judgment but with the eye and ear and heart; no American writer will ever have a more alert ear, a more attentive eye, or a more ardent heart than his.
