Construction commenced in 1756 in Nantes, shortly after the outbreak of war between France and Britain. The vessel was originally intended as a privateer named
Maréchal de Richelieu, but was purchased by the French Navy in December 1757. Completed in early 1759, she was commissioned into that Navy as the 28-gun
frigate Écho and assigned to duties in the French Caribbean. As built,
Écho was long with a short keel and an unusually broad
beam of . Her sides were low, with a
hold depth of only , nearly less than similar vessels such as the privateer
La Marie Victoire. Her armament as a French vessel was 28 guns, comprising 24
nine-pounder cannons and four smaller weapons. After her capture by the British these four smaller guns were removed. Her crew numbers as a French vessel are unrecorded; the designated Royal Navy complement was 160 men. ==Citations==