The 'synaesthesia' works if you imagine he is talking about buttery biscuit bass (i.e. the bassline of the music) rather than buttery biscuit base...

I work at Sussex University in the UK, in the synaesthesia research group allied to Julia Simner's, and we are always looking for people who have this or any other kind of synaesthesia. If you'd like to take part in our research, or just want to know more, please have a look at our website: www.syn.sussex.ac.uk

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