A method is provided for adapting an applied volume gain in an audio amplifier controlling at least one loudspeaker of an enclosure according to a desired volume gain selected by a user on a scale increased by a maximum desired volume gain, including determining effective intensity applied to the loudspeaker, calculating maximum volume gain from the desired volume gain, an effective intensity applied to the at least one loudspeaker, thermal characteristics of the loudspeaker, and the maximum desired volume gain, then calculating a variable applied volume gain according to an increasing monotonic function providing a variable applied volume gain according to the desired volume gain such that the image of the maximum desired volume gain by the monotonic function is equal to the maximum volume gain, and applying to the amplifier as applied volume gain, the minimum of the desired volume gain and the variable applied volume gain.