Salve Quinte Juli

Roman chants? Em, the carmen Salii would have been chanted, but we have only some fragments of it. Horace's Carmen Saecularum was intended for a chorus to recite/sing, so that might be called a chant. There were some magical cures chanted, recorded by Varro, Cato, and a couple others. And I think it is Horace who has a chant to Venus, intended as a love charm. (Virgil was noted by Pliny for his collecting such love spells, but I don't recall any we may have today.) And then there is the Carmen Fratrum Arvalum:

ENOS LASES IUVATE! ENOS LASES IUVATE! ENOS LASES IUVATE!
NEVE LUE MARMAR SINS INCURRERE IN PLEORIS.
NEVE LUE MARMAR SINS INCURRERE IN PLEORIS.
NEVE LUE MARMAR SINS INCURRERE IN PLEORIS.
SATUR FU, FERE MARS, LIMEN SALI, STA BERBER
SATUR FU, FERE MARS, LIMEN SALI, STA BERBER
SATUR FU, FERE MARS, LIMEN SALI, STA BERBER
ENOS MARMOR IUVATO, ENOS MARMOR IUVATO, ENOS MARMOR IUVATO!
TRIUMPHE! TRIUMPHE! TRIUMPHE! TRIUMPHE! TRIUMPHE!

My poor effort at translation has:

Lares assist us, Lares delight us, Lareas come to our aid!
Neither plague nor ruin, Marmor, allow to be visited on us.
But if however we are invaded, like Mars we shall leap across our borders
To sate you with the blood of our enemies and stay the barbarians.
Marmor assist us, Marmor defend us, Marmor come to our aid.
Triumph, triumph, triumph, triumph, triumph!

Vale optime