This disclosure relates to varying load and modulation applied to each of multiple frequency subchannels based on anticipated attenuation experienced by those subchannels. Communicating data includes identifying a static component of a transmission medium for wideband communications having at least two subchannels, determining a function of noise or attenuation versus frequency for the static component, selecting wideband modulation schemes for the subchannels based on the function determined, and communicating a data signal over the subchannels. Independent demodulation functions may be applied to at least two of the subchannels.