In this paper, we propose a signal transformation, using basic signal processing, to combine the individual time synchronised channels of a low-bandwidth multi-channel signal, like the EEG into a single-channel high-bandwidth signal, like audio. Further the signal transformation is bi-directional, namely the multi-channel signal can be reconstructed back from the single-channel signal. As a motivation, such a transformation when applied to EEG signals (a) allows processing a multi-channel signal as a single-channel, and (b) allows the use of single-channel pre-trained models, for multi-channel signal processing and analysis. We demonstrate the usefulness of the proposed signal transformation on a publicly available EEG dataset.