Chris Watson's art is epic, transporting and inspirational, and at the same time utterly straight-forward. In the 1970s he founded the Sheffield post-punk band Cabaret Voltaire; now 60, he records wildlife and natural environments all over the world.
In the first part of this lecture/performance he talked about the Galapagos and Icelandic glaciers, about train journeys across Mexico and Scott's Antarctic hut where nothing has changed since the explorer walked out. "Just the sound of wind catching the chimney," he described. "Like listening back in time to next-to-nothing." There was unfussy poetry to the way he explained his work.
A broader climate change message was woven in lightly but persuasively: by making us imagine these environments, Watson's recordings also make us care.
His performance consisted of a 40-minute surround-sound live mix of oceanic sounds. Starting on Shetland with a screeching cacophony of coastal birds, his hydrophones soon dipped under the surface to follow seals, dolphins and pistol shrimps.
Each animal was introduced one by one, like characters making entries in an opera. Waves provided ostinatos and pedal notes; the underwater acoustic made a booming acoustic backdrop.
Eventually we arrived at humpback whales in the Dominican Republic, where the males sing three-hour song cycles - "Wagnerian!" Watson chuckled - with sounds so powerful that their vibrations stimulate the females to ovulate.
I noticed that everyone in the audience around me had their eyes closed: this was vivid, fascinating listening.
Whether to attribute spiritual or musical meaning to the noises was up to each listener. For me, it was about simply envisaging these magnificent marine singers. The 40 minutes were gone in a flash.