"Associations are accidents of sound, in which words as things gain unsuspected power." So says Susan Wolfson in her essay, "Sounding Romantic: The Sound of Sound," which collects and interprets such data as:
"Those of us who may have been thinking of the path of poetry, those who understand that words are thoughts and not only our own thoughts . . . must be conscious of this: that, above everything else, poetry is words; and that words, above everything else, are, in poetry, sounds." - Wallace Stevens
Coleridge's "Man communicates by articulation of Sounds..." - and his notebook entry:
"N.B.—In my intended Essay in defence of Punning—(Apology for Paronomasy, alias Punning) to defend those turns of words,
che l'onda chiara
E l'ombra non men cara,
In certain styles of writing, by proving that Language itself is formed upon associations of this kind . . . that words are not mere symbols of things & thought, but themselves things—"
(Notebooks 3: 3762)
The Ice was here, the Ice was there,
The Ice was all around:
It crack'd and growl'd, and roar'd and howl'd—
Like noises in a swound!
... about which Wolfson remarks, "In this ice-sounding, noise similizes the assault: swound is a ghost of sound, a rhyme-word that lurks in the aural field without precipitating."
Eliot's "auditory imagination" ("the feeling for syllable and rhythm, penetrating far below the conscious levels of thought and feeling, invigorating every word").
Wordsworth's Note to The Thorn on the mind's adhesion "to words . . . as things, active and efficient, which are of themselves part of the passion."
... Dorothy Wordsworth's absorption of the poet's lines:
"here is something inexpressibly soothing to me in the sound of those two Lines
Oh listen! for the Vale profound
Is overflowing with the sound—
I often catch myself repeating them in disconnection with any thought, or even I may say, recollection of the Poem."
The sound of the word sound: "There's the Latin sonare: the very word is like a bell for poets, the fount of sonnet ("little sound") and persona ("sounding through"). Petitioning for, and sometimes crowding into the same literal space, and open for punning (O Pun! to honor Charles Lamb), there are Old English tributes of sound (test the depths); sound from a different source for healthy (sane), and with a slight shift, as in sound asleep, whole, entire; and the waters (more etymology yet) in Milton's poetry of Creation, "Sounds and Seas" (PL 7.399)—poignantly sounding sees, what the blind poet does no more."
And lots else.
When I was a curator doing audio restoration of poetry recordings, I was struck by how the birth of audio technology took place when Whitman and Tennyson and Browning were still around to be recorded: it was a 19th century technology. Amazing to think that we almost could have had Hopkins' own voice to hear today!
Wolfson's essay is from a volume called “Soundings of Things Done”: The Poetry and Poetics of Sound in the Romantic Ear and Era," which she edited; it's online, as a "Romantic Circles Electronic Edition." There are also essays by James Chandler, Garrett Stewart, and Adam Potkay.
Writing from the punning senses of individual words, taken for granted in both Modernist and Post-Modernist poetry, actually has Romantic roots.