The soft warm sound of flowing, bubbling water from the fountain pervades the mid-range frequencies. Underneath is the ever-present yet always changing low road of traffic bleeding in from the Passage de Colon. A taxi driving up the one-lane road down the north-west side of the square dominates the spectrum, surprisingly loud against the background. Its doors slam as people disembark to my left, punctuating the ambiance even more than its progress did.
Even just a few steps away from the fountain towards the Basilica the tonal qualities of the fountain change. A previously masked droning sound comes to the fore - it too - like the traffic and the fountain is constantly in flux, always changing, always the same. Not a particularly large amount of variation, but present nonetheless. I decide it is a vacuum cleaner, though due to the constant nature of the sound and the qualities of the space working out exactly where it is coming from is almost impossible.