A method for the preparation of a support area and for acoustic management: - on an aircraft turbomachine (3,12) comprising an air inlet cone, and/or - on a nacelle (1,10) of such a turbomachine (3,12) comprising: -- at least one outer structure comprising at least one outer annular casing, and possibly: -- an inner structure comprising a fairing of a turbojet engine (3,12,19), which engine (3,12,19) of a turbojet having an air inlet cone comprises a fan, the inner structure of the nacelle then defining, with the outer structure, an annular air vein for secondary air, and -- an exhaust nozzle comprising an outer primary nozzle sleeve and an inner primary nozzle tip defining between them an outlet channel for a primary air flow exciting the engine (3,12,19) of the turbojet, in which method: - on at least said support area of the turbomachine (3,12) or of the nacelle (1,10) is reserved at least one recess recessed with respect to a surrounding general surface of said support (3,12) defining a surface for contact with the moving air (21,28,45): -- in the turbomachine (3,12), on the air inlet cone, or -- on the nacelle (1,10), the recess being adapted to removably receive at least an acoustic panel and a non-acoustic panel, both having a surface for contact with the moving air (21,28,45), one in replacement of the other, - depending on an acoustic or an aerodynamic criterion, one said panel (30,32) is removed from the recess in which said panel was contained and is replaced by a replacement panel (30,32) adapted to replace it and which has a surface for contact with the moving air (21,28,45), said replacement panel being an acoustic panel if the panel removed is non-acoustic, and vice versa. - on an aircraft turbomachine (3,12) comprising an air inlet cone, and/or - on a nacelle (1,10) of such a turbomachine (3,12) comprising: -- at least one outer structure comprising at least one outer annular casing, and possibly: -- an inner structure comprising a fairing of a turbojet engine (3,12,19), which engine (3,12,19) of a turbojet having an air inlet cone comprises a fan, the inner structure of the nacelle then defining, with the outer structure, an annular air vein for secondary air, and -- an exhaust nozzle comprising an outer primary nozzle sleeve and an inner primary nozzle tip defining between them an outlet channel for a primary air flow exciting the engine (3,12,19) of the turbojet, -- at least one outer structure comprising at least one outer annular casing, and possibly: -- an inner structure comprising a fairing of a turbojet engine (3,12,19), which engine (3,12,19) of a turbojet having an air inlet cone comprises a fan, the inner structure of the nacelle then defining, with the outer structure, an annular air vein for secondary air, and -- an exhaust nozzle comprising an outer primary nozzle sleeve and an inner primary nozzle tip defining between them an outlet channel for a primary air flow exciting the engine (3,12,19) of the turbojet, - on at least said support area of the turbomachine (3,12) or of the nacelle (1,10) is reserved at least one recess recessed with respect to a surrounding general surface of said support (3,12) defining a surface for contact with the moving air (21,28,45): -- in the turbomachine (3,12), on the air inlet cone, or -- on the nacelle (1,10), the recess being adapted to removably receive at least an acoustic panel and a non-acoustic panel, both having a surface for contact with the moving air (21,28,45), one in replacement of the other, -- in the turbomachine (3,12), on the air inlet cone, or -- on the nacelle (1,10), - depending on an acoustic or an aerodynamic criterion, one said panel (30,32) is removed from the recess in which said panel was contained and is replaced by a replacement panel (30,32) adapted to replace it and which has a surface for contact with the moving air (21,28,45), said replacement panel being an acoustic panel if the panel removed is non-acoustic, and vice versa.