Squally Showers (redux)

Squally Showers, originally part of my PhD portfolio, represented one of the toughest challenges to bring to a web-based version. This live, simultaneous sonification of thirty shipping-forecast areas was deliberately written to occupy a place in my portfolio of writing for “large forces” (my Wagnerian period). The piece was designed for installation, ideally taking advantage of spatialisation-either over an eight-speaker ring or, in the ideal setup, thirty individual channels¹ placed to reflect the geographical position of the areas-so that listeners could perceive and wander around the different regions.

For documentation purposes I rendered stereo files, but this was never intended as the final version. My feeling was that simply porting the thirty-channel version to a webpage would produce an unholy mass, even if technically feasible: unlike the tools used for my PhD (Pure Data or SuperCollider), the Web Audio API is not good at handling large numbers of simultaneous objects. Works such as The Beach Buoys and Notes from Underground went through similar curtailment or optimisation.

One alternative-again discussed and dismissed for Notes from Underground-was a point-and-click interactivity that isn’t the direction I want to take these works. After some rumination I adopted a scheme where the droning “organ stops” layer, which takes up the most sonic bandwidth, tours the forecast areas, gently crossfading between layers over a six-hour sequence. Although it would be more in keeping with the structure of the broadcast to stick to the prescribed reading order (beginning with Viking), I introduced variation by designing a scheme where the starting area rotates with each forecast. Other layers pick six areas at a time, which also rotate; each area takes its turn during the six-hour forecast period, but the stereo picture is never overloaded.

Part of me sees this as a compromise-a minimised version of the original piece - and part of me wonders if it’s actually a new piece, albeit one composed in the spirit of the original. This has been a theme in the resurrection of these PhD works, and for those significantly changed I’ve applied a “redux” to the title. There’s no fixed threshold: “redux” simply signals that something fundamental has shifted - whether the synthesis engine, the source data, or the internal logic of the piece.

The sonification scheme behind Squally Showers draws on familiar elements from this PhD portfolio but takes a layered approach that is distinctive compared with the monophonic nature of many of the other works. The “organ stops” layer is a continuous drone constructed from time-stretched versions of Sailing By - the Shipping Forecast “theme song” (composed by Ronald Binge in 1963). This piece of music is heard before the 00:48 broadcast and serves two purposes: as a recognisable ident allowing sailors to tune to BBC Radio 4, and to fill the time between the end of the news bulletin at 00:45, allowing the forecast to begin at precisely 00:48.

In Squally Showers, thirteen versions of Sailing By are subjected to lengthy nested time-stretches ranging from six hours to roughly twenty-seven minutes (each “stop” is six hours divided by 1, 2 … 13). The Beaufort wind readings for each area (1 to 12) are used to “pull out” these organ stops (increase their amplitude) in sequence - so a forecast of “4 to 5, 3 later” produces a sequence of 4, 5 and 3. Each stop is also pitch - shifted: stop 1, lasting six hours at unchanged pitch, sounds permanently, while stops 2 to 13 become progressively more discordant according to an algorithm developed by Campbell D. Foster. Lighter winds produce more consonant intervals such as the perfect fifth and octave; hurricane-force winds produce the highly dissonant tritone.

A second layer features samples of BBC announcers reading the forecast in a sort of chant. The depth of this chant is determined by the sea state. Calm seas (slight, moderate) result in a shallow range of speakers, whereas rough seas mean up to twenty-four different voices. There are eight sea states possible: at the calmest end of the scale three voices are heard at intervals of ten seconds, whereas at the roughest twenty-four voices are heard at intervals of three seconds. Reverb is added in greater amounts according to the visibility, so in poor visibility only a reverberant haze of the original voice is heard.

A third layer is made up of the sound of ships’ bells. There are two bell sounds, triggered by Morse-code patterns for each area name - one bell sample for dot and one for dash. This Morse code is cycled through at a tempo determined by the wind speed in that area (each shipping area has a base tempo of ten seconds plus the number of letters in its name - so the tempo for Lundy would be fifteen seconds - divided by the Beaufort wind speed). The faster the wind, the brisker the tempo of the ships’ bells. They are also subject to the same visibility-and-reverb mapping as the announcers’ voices.

In the original piece, some offline pre-processing and a piece of software called GetIPlayer allowed me to collect the most recent forecast from the BBC’s “listen again” feature and incorporate it into the soundscape. This is not possible (or at least I haven’t discovered a method) in the web version, so a layer in the spirit of this has been incorporated. Samples of the distinctive opening (“And now the Shipping Forecast, issued by the Met Office on behalf of the Maritime and Coastguard Agency”) and closing variations (“that was the Shipping Forecast” / “that concludes the Shipping Forecast”) are played at intervals determined by the number of gale warnings - more gales meaning a more active layer.

The original version of Squally Showers is documented in my PhD thesis.

¹ Shipping Forecast aficionados will know there are actually thirty-one areas, but Trafalgar only features in the late-night broadcast. As the piece accesses the forecast four times a day as published for continuity (and ease of programming), Trafalgar is omitted. ↩