Frequently Asked Questions

What does the OscylinderScope do?


The OscylinderScope is an interactive artwork/exhibit which explores the nature of sound by directly translating the vibration of musical strings into visible waves.

The OscylinderScope displays the oscillation of a string as a steady state sinusoidal wave which can be observed, measured or otherwise analyzed.

Your left hand starts the large horizontal drum spinning, Then your right hand strums three strings of an acoustic guitar. White lines engraved into the black cylinder scan the strings as they vibrate, so that they appear as wavy lines. This unexpected phenomenon is the heart of the OscylinderScope.

Each of the three guitar strings displays a different wave pattern according to its frequency. The displayed waveform looks and acts like the trace on an electronic oscilloscope Use your foot on the pedal to change the tension of the strings to raise the pitch of the instrument and increase the frequency of the displayed waveforms.

What does the OscylinderScope offer the visitor?

The OscylinderScope is fun.

Even if the visitor is too young or too preoccupied to grasp the concept of wave theory, actively strumming and spinning, watching and listening to the OscylinderScope is a "wow" experience. Visitors of all ages enjoy seeing this wacky gadget make guitar strings look like a wavy lines.

The OscylinderScope is educational

Each element of the OscylinderScope is open to examination. The curious visitor is encouraged to slow down or stop the hand powered drum and figure out "How does this thing work?". The accompanying graphic text helps each visitor with his or her own self-motivated, experimental search for understanding.

Of course, the OscylinderScope is an instrument for exploring the nature of sound and wave theory. Particularly evident is the relationship between frequency of vibration and the sound produced by a vibrating string.

As the frequency of oscillation of an OscylinderScope string increases (i.e. a shorter or tighter vibrating string is observed) the distance between peaks of the waves observed along the length of the string (wave length) decreases, and the number of waves per unit distance increases. A higher pitched sound is heard.

As a string is plucked more violently, the observed frequency remains constant while the horizontal distance between the peak and the trough (the amplitude) of each wave increases. A louder sound of the same pitch is heard.

The OscylinderScope gives wave theory a "show me" believability which motivates experimentation and understanding.

The OscylinderScope also demonstrates:

* the "persistence of vision" phenomenon, an optical illusion which makes motion catalogPages and television possible. * the notion of "scanning per unit of time" used in graph making and the electronic oscilloscope.

The OscylinderScope is an ideal instrument for the type of inquiry based learning by experimentation which is essential to today's interactive museum.

How does the OscylinderScope work?

The musical strings are black, and they cannot be seen when the black areas of the drum are behind them. However, it is easy to see those segments of the strings which have the narrow white stripes behind them. As the cylinder spins, the white stripes scan the vibrating strings and transform them into thin wavy lines.

A sinusoidal wave appears as the white stripes scan the length a vibrating string. Each passing white stripe displays the profile of a small segment of a string at the instant in which the stripe is behind that segment. The next passing white stripe profiles the same segment an instant later. Since the string has moved slightly sideways, the persisting image is perceived by the viewer as a solid wavy line.

When the drum rotates at a speed at which the displayed wave appears steady, the vertical distance between the observed peaks of the displayed wave is equal to the distance that a stripe has scrolled during the time period of one complete oscillation of the musical string. Thus, the relative frequency of the vibrating string is displayed. The horizontal distance between the peaks and troughs of the displayed wave corresponds to the amplitude of the oscillation of the string.

How and where has the OscylinderScope been displayed?

The OscylinderScope requires only normal room lighting conditions and no electrical connection.

Each OscylinderScope is supplied complete with a graphic panel with text which can be mounted on either side of the piece.

The OscylinderScope requires an area of about 4 feet by 4 feet and is 6 1/2 feet tall. The piece weighs about 100 pounds but has a crated shipping weight of 200 pounds. If crated, the piece can be delivered by common carrier and can be easily assembled with common hand tools.

OscylinderScopes are currently on display at:

* The Exploratorium in San Francisco * Technorama Museum in Winterthur, Switzerland * The Science Museum of Western Virginia at Roanoke *The Children's Discovery Museum in San Jose, Ca. (November 1998 * An Exploratorium traveling exhibition.

I'm sold. How do I get one?

The price of the OscylinderScope is currently (Oct. 1998) $9,500.00 (F.O.B. San Francisco, uncrated) with a 120 day delivery date.

To order or learn more about the OscylinderScope, Lariat Chain or the Art Machines traveling exhibition contact:

Norman Tuck 379 25th Avenue San Francisco, CA 94121

phone/fax 415 666-3675 email norman@sirius.com