Music 17 -- Quiz #1

Note: There are a lot of ways of saying the same thing.
Much partial credit will be given.

Part I -- Definitions

Choose 10 of the following terms and provide concise definitions.

ADC
Analog-to-Digital Convertor. Device that converts analog voltages into binary numbers.

Amplitude
Magnitude of the pressure fluctuations caused by a vibrating system.

Binary
Base 2 number system which uses only 1's and 0's.

Browser
Software that enables viewing of html data.

Frequency
How many cycles of a waveform occur per unit time. Often expressed in Hz (cycles per second).

MIDI
Musical Instrument Digital Interface. A serial communications protocol and hardware specification.

Note-On
A MIDI message containing pitch (note number), channel, and velocity. "Tells" receiving device to play a note.

Oscillator
A vibrating source of energy.

Sampling Rate
The rate at which the ADC measures voltages and converts them into binary numbers.

Sequencer
Device that records and plays back MIDI commands.

Tone Generator
Electronic device that produces sounds (often in response to MIDI commands).

Transducer
Device that converts one form of energy into another.

URL
Universal Resource Locator. An "address" on the web.

Waveform
Graph of amplitude vs. time.

Part II -- Electronic Communication Examples

For each of the following scenarios, answer the following questions:

(1) What type of information is being exchanged?

(2) What is the sending device?

(3) What is the receiving device?

1. You have written an e-mail message to your high school teacher; you have just clicked the "Send" button.

1. Mostly text (encoded in binary form)
2. Your e-mail client.
3. Your e-mail server.

2. You are browsing the Furman web site; you have just clicked on a link and the new page is starting to appear.

1. Multimedia (encoded in html code).
2. The Furman web server.
3. Your browser.

3. You are recording in Musicshop.

1. MIDI commands
2. The X5 (or other synthesizer or MIDI controller).
3. The computer (running Musicshop).

4. You are listening to a CD.

1. (digital) audio.
2. The DAC in the CD deck OR the speaker/headphones.
3. The speaker OR your ears.

Extra Credit

When you change the speed of a tape recording, the pitch will change. Why can you change the speed of a Musicshop recording without changing the pitch?

Because a Musicshop file consists of MIDI commands, NOT AUDIO. MIDI commands are unaffected by the rate of playback.