A method for improving acoustics of amplitude modulation (AM) audio signal, comprising: amplifying and mixing, with an amplitude modulation (AM) front-end module, an analog AM signal and an automatic gain control (AGC) signal from an AGC module; converting and sampling, with an analog-digital converter and down-sampling module, the amplified and mixed signal to generate a digital AM signal; digitally mixing, with a digital mixer module, the digital AM signal to generate a first digital AM envelope signal; compensating, with an AM compensator module, the first digital AM envelope signal by an AM compensating AGC signal from the AM compensator module to generate a second digital AM envelope signal; demodulating, with a demodulation module, the second digital AM envelope signal; and outputting, with an output module, a demodulated AM audio signal.

Disclosed is a frequency amplitude modulation (FAM) transmission apparatus and method by combining a frequency modulation (FM) signal and a digital modulated amplitude modulation (AM) signal. A FAM transmission method includes receiving an FM signal created by modulating an audio signal that includes audio information for mono or stereo broadcasting based on an FM scheme; receiving a digital pulse created by modulating digital data used to provide an additional service for the mono or stereo broadcasting based on an amplitude modulation (AM) affiliated digital modulation scheme; creating an AM signal by by adjusting the digital pulse to have a value greater than 0; and creating a FAM signal by combining the FM signal and the AM signal.