In the Comments Below Let Us Know Your Ideas for Projects Around Acoustics!
The theme this month is Acoustics and it comes from an idea from neuromodulator. This competition is an opportunity to do projects around sound and can involve projects that involve infrasound, audible sound, ultrasound, amplifiers, piezoelectric material, spectrum analyzers, and more! Acoustics (from the Greek word akoustos which means "heard") is the science of how sound is produced, transmitted, controlled, and the effects of sound. Acoustics play a huge role in music, especially when it comes to musical scales and instruments. Concert halls and auditoriums take into account the relationship between space and the listener with a good acoustic design taking into account issues such as reverberation time; sound absorption of finished material; echoes; acoustic shadows; sound intimacy, texture, and blend; as well as external noise. Architectural modifications can be made to improve sound such as adding orchestral shells, canopies, and undulating or angled ceilings and walls.
Your project can be anything involving sound or using a transducer for converting one form of energy into another. In an electroacoustic context, a transducer converts sound energy into electrical energy (or vice versa). Your project can involve electroacoustic transducers that convert a sound wave to some form of electric signal such as loudspeakers, microphones, particle velocity sensors, hydrophones and sonar projectors. The most widely used transduction principles are electromagnetism, electrostatics and piezoelectricity.
An ordinary acoustic guitar generates sound entirely through vibration. If you pluck a string, it vibrates back and forth, transmitting sound energy into the hollow wooden body of the guitar, making it resonate and amplifying the sound. An electric guitar produces sound through electromagnetism, electromagnetic induction to be precise. The metal strings of an electric guitar act as dynamos: producing electricity when you move them. Under the strings, you will find electricity-generating devices called pickups. Each pickup consists of one or more magnets with hundreds or thousands of coils around them. The magnets generate a magnetic field that passes up through the strings making them partially magnetized and when they vibrate, they make a very small electric current flow through the wire pickup coils. The pickups are hooked up to an electrical circuit and amplifier, boosting the small electric current and sending it to a loudspeaker, usually an "amp" which consists of the amplifier and loudspeaker in a simple unit.
Transducers in most common loudspeakers, including woofers and tweeters, are electromagnetic devices that generate waves using a suspended diaphragm driven by an electromagnetic voice coil, sending off pressure waves. Electret microphones and condenser microphones employ electrostatics—as the sound wave strikes the microphone's diaphragm, it moves and induces a voltage change. The ultrasonic systems used in medical ultrasonography employ piezoelectric transducers. These are made from special ceramics in which mechanical vibrations and electrical fields are interlinked through a property of the material itself.
Pythagoras, often described as the first pure mathematician, is credited with making one of the first discoveries around sound in the sixth century BC. In what is now known as the law of strings, he noted the relationship between the length of a vibrating string and the tone that it produces. He noticed that these vibrating strings produced harmonious tones when the lengths of strings are whole numbers, something that could be extended to other instruments. Pythagoras himself was a fine musician who played the lyre. He enjoyed using music as a means to help those who were ill.
The modern study of sound is said to have originated from Galileo Galilee, whose interest in sound is said to have been inspired by his father who was a mathematician, musician, and a composer of some repute. He elevated sound to a science by studying vibrations and the correlation between frequency and the source of sound. In the Discorsi Galileo thought out the vibrating complexion of sounds, and asserted that the pitch was correlated with the number of vibrations. He was unable to count them, so he did not use the word “frequency,” but spoke of the “number of vibrations in the same time.”
Acoustics is the study of all mechanical waves in gases, liquids, and solids and encompasses the topic of vibrations, sound, ultrasound, and infrasound. The audio range of the spectrum is between 20 Hz and 20,000 Hz. This range is important because its frequencies can be detected by the human ear.
Very low frequency, beyond what our ears can hear refers to infrasound while anything operating at very high frequency is ultrasound. The ultrasound range is commonly used for medical diagnostics such as sonograms. An ultrasound scan uses high-frequency sound waves to create images of the inside of the body. A pregnancy ultrasound is a test that uses high-frequency sound waves to image a developing baby as well as the mother's reproductive organs. An ultrasound, also called a sonogram, can help monitor normal fetal development and screen for any potential problems. Ultrasound scans, or sonography, are safe because they use sound waves or echoes to make an image, instead of radiation. Ultrasound scans are used to evaluate fetal development, and they can detect problems in the liver, heart, kidney, or abdomen. They may also assist in performing certain types of biopsy. Animals such as dogs, birds, and bats can hear ultrasound. The high pitched ultrasound used by bats in echolocation is perfect for navigating at night because these noises are easily reflected back to the bats by objects in the environment:
Anything under the 20 Hz range is known known as the infrasonic range. Sources of infrasound in nature include volcanoes, avalanches, earthquakes and meteorites. Early studies of infrasound of hurricanes offer some hope of deciphering the infrasound signature of an approaching hurricane. Monitoring of infrasound seems to be one of the best ways for detecting atmospheric nuclear tests. A number of animals produce and use sounds in the infrasonic range. Animals such as elephants, whales, and hippopotamus use infrasound to communicate over long distances. Infrasound frequencies travel well through objects instead of being reflected so its good for long distance communication. because they travel well through objects instead of being reflected. The rumbling vocalizations of elephants have been measured at frequencies as low as 14 Hz, detectable at a range of 10 km.
Analytic instruments such as the spectrum analyzer facilitate visualization and measurement of acoustic signals and their properties. The spectrogram produced by such an instrument is a graphical display of the time varying pressure level and frequency profiles which give a specific acoustic signal its defining character.
Your Chance to Win
|Be Original||Stick to the Theme|
|List the Steps||Submit Video Proof|
|Homemade Electric Guitar||Tube Amp on a PCB|
|One Grand Prize Winner Wins a $200 Shopping Cart!||Three First Place Winners Win a $100 Shopping Cart|
Your Project, Your Ideas!
Every month you'll have a new poll where you'll get to decide an upcoming project competition, based on your interests, that will take place a couple of months in advance. Themes are broad in scope so that everyone can participate regardless of skill set.
What are Monthly Themes?
What are Monthly Theme Polls?
Step 2: Post in the comments section below to begin a discussion on your idea. Videos, pictures and text are all welcomed forms of submission.
Step 3: Submit a blog post of your progress on your project by the end of the month. You are free to submit as many blog entries as you like until the beginning of the next theme.
Be sure to include video proof of your project!
Visit: Acoustics or tag your project blog AcousticsCH
You have until March 16th End of Day to submit your completed project!
A jury consisting of your peers will judge project submissions!