The Rumble Strip

This is one weird musical instrument. You have seen gourd scrapers, maybe even those wooden frogs which you rub on their backs to make them croak. Driving a road with grooved edges makes your car vibrate, sometimes in an interesting way. Well this will be about 100 feet long and 8 feet wide, with two parallel paths you can go down. Maybe by wheeling luggage or with specially supervised skateboarders. But the easiest way to get a rhythmic timbral noise out of them is to run or walk while dragging a Sonic Broom (see earlier post; there are many kinds and each one sounds different). In this case the track itself does not make the noise (as a gourd would); it is the scraper that broadcasts the vibrations and is therefore the instrument.

I have found a few suitable textured materials that can be cut, arranged and glued to the backing board (which will be painted); lucite lighting screens, slip-resistant stair covering, and artificial turf. Each makes a different sound. How to compose them?

Maybe I will just lay them out in an interesting musical sequence that has a climax and some surprises along the way. I have also thought about using them to model something about the occasion and place: it is the 150th anniversary of the state of Minnesota.

What if the path were 150 feet long, each foot representing one year, and I placed significant noises at years where there was extreme weather (it has happened every few years since 1858 with some regularity).

Or a slice of the state's terrain from south to north? There could be some freaky sounds towards the north woods and lakes.















Or even the location of coffee shops throughout the state? (Thanks, Google Earth!)





Now I have heard the effect of the prototype Strip I think it could be made to resemble speech. It has a gravelly vocal quality to it. What if I could take a recorded speech (what one should it be????), analyze the rhythm and basic inflections of the voice, and measure it out over the whole length? You could cause the pathway to speak something almost intelligible if you ran along it at just the right, steady speed...
Here, for instance, is 30" of Paul Wellstone's 1996 victory speech. It has some repetition of simple phrases that could be interesting, even if the content itself isn't earth-shattering.