the invention relates to a method and apparatus for achieving maximal coding gain for audio transmission . more particularly , at a chosen sample rate and frequency range value , an audio input signal is downsampled to the sample rate , encoded and transmitted at a given bit rate . at the receiving end , the downsampled signal is decoded and upsampled to the original or other suitable sample rate . the upsampled signal is then audibly output . since resampling ratios using “ small ” numbers prove to be more computationally efficient , this method and apparatus supports resampling ratios which imply both standard and non - standard sampling ratios in the codec .