<sod>Some transcriptions were recorded with a vertically modulated "hill and dale" groove, as this was found to allow not only a deeper bass due to the fact that turntable rumble was laterally-modulated in early radio station turntables, but also an extension of the high-end frequency response, neither of which was necessarily a great advantage in practice because of the limitations of [[AM broadcasting]]. Today we can enjoy the benefits of those higher-fidelity recordings, even if the original radio audiences could not.<eod>
<sod>Some transcriptions were recorded with a vertically modulated "hill and dale" groove, as this was found to allow not only a deeper bass because turntable rumble was laterally-modulated in early radio station turntables, but also an extension of the high-end frequency response, neither of which was necessarily a great advantage in practice because of the limitations of [[AM broadcasting]]. Today we can enjoy the benefits of those higher-fidelity recordings, even if the original radio audiences could not.<eod>