Parker & Coward, 1888
Even bigger than Pinatubo was Krakatoa, which erupted in 1883 (James Joyce and Virginia Woolf were 1!) and was one of the most destructive eruptions ever recorded. A passenger on a steamer reported that the skies and ocean were lawn green. Then there’s this tidbit from wikipedia which illustrates the massive scale of the eruption:
A series of four huge explosions almost entirely destroyed the island. The explosions were so violent that they were heard 3,110 km (1,930 mi) away in Perth, Western Australia, and the island of Rodrigues near Mauritius, 4,800 km (3,000 mi) away. The pressure wave from the final explosion was recorded on barographs around the world. Several barographs recorded the wave seven times over the course of five days: four times with the wave travelling away from the volcano to its antipodal point, and three times travelling back to the volcano. Hence, the wave rounded the globe three and a half times. Ash was propelled to a height of 80 km (50 mi). The sound of the eruption was so loud it was reported that if anyone was within ten miles (16 km), they would have gone deaf.
There’s also this article: The Sound So Loud That It Circled the Earth Four Times, which provides some useful comparisons of how loud such a sound might’ve been. In a nutshell, so loud that we don’t so much hear it as feel it:
The human threshold for pain is near 130 decibels, and if you had the misfortune of standing next to a jet engine, you’d experience a 150 decibel sound. (A 10 decibel increase is perceived by people as sounding roughly twice as loud.) The Krakatoa explosion registered 172 decibels at 100 miles from the source. This is so astonishingly loud, that it’s inching up against the limits of what we mean by “sound.”
There’s a limit to how loud a sound can get. At some point, the fluctuations in air pressure are so large that the low pressure regions hit zero pressure — a vacuum — and you can’t get any lower than that. This limit happens to be about 194 decibels for a sound in Earth’s atmosphere. Any louder, and the sound is no longer just passing through the air, it’s actually pushing the air along with it, creating a pressurized burst of moving air known as a shock wave.
The article illustrates this with an amazing amateur video that captures the shockwave of a smaller eruption rushing across the sky and hitting the boat like a gunshot: