"pure voice" is a correct and usable phrase in written English.
You can use it to mean a voice that is free from any artificial sound or technique, such as when someone speaks or sings with a natural, unforced or unaffected sound. For example, "When she sang, her pure voice captivated the audience."
"I've always loved a pure voice or a pure instrument," he says at one point.
We see that beautiful little boy with the pure voice, the moves, the joy.
The 32-year-old Jaroussky's exceptionally pure voice, combined with his cherubic good looks, have won him a passionate following.
Her pure voice, and the echoing space into which she projected it, seemed made for each other.
Arianna plays the harp and sings in a light, pure voice; she has released a record under her own name.
He's got the most incredible, pure voice – it's uplifting, and any time I hear it, it makes me feel hopeful.
They brainstormed -- Pure Voices, and the like -- but finally stood firm.
The women in particular are notable for their well-blended sound and pure voices, which soar rapturously but with appropriate decorum in the slightly reverberant acoustics of the Chapel of Hertford College, Oxford, where the disc was recorded.
Probably a bit of both, as these girls' pure voices rise angelically, as they rampage across the city and their home turf in an alcoholic, drug-fuelled, sex-mad 24-hour odyssey of self-discovery and growing up.
Much of the sacred music and opera roles sung today by Jaroussky or by mezzo-sopranos like Cecilia Bartoli were originally composed for Farinelli and his peers — male singers who were castrated before they reached puberty in order to preserve their high, pure voices.
The show also dwells on the children that she hasn't given birth to, and is shot through with the hauntingly pure voices of two young girls whose sweet directness is pointedly contrasted with Meow Meow's attempts to face down the world with sequins and pill-popping.
