With air, a sound source creates waves of high and low pressure (compression and rarefaction) and these are received and perceived as the eardrum vibrates and converts those air waves into electrical impulses the brain recognizes as sound.
In electrical sound transmission, current is alternated between positive and negative and converted into air pressure waves by means of a coil wrapped around an electromagnet (this makes use of the phenomenon known as "induction" which I'll get into later) attached to a membrane which, hopefully, you recognize as a speaker. A microphone, at least a dynamic one, is a speaker in reverse. Sound pressure waves vibrate a membrane attached to a coil around a magnet which converts them into analogous electrical waves. Notice how I snuck in the word, "analogous?" Indeed, that is where the word, "analogue" comes from.
To begin this journey, travel all the way back to 3000 BC when the Egyptians depicted the practice of using electrical discharges from Nile catfish in the treatment of various ailments in tomb wall paintings. Are you done looking around? Good, because this was the extent of human interaction with electricity until almost 600 BC when a Greek named Thales discovered that rubbing a piece of amber on a cat's fur caused it to attract light objects. What he was doing rubbing cats with amber is between him and the Gods but this was an early observation of static electricity. A millenium later- I'm sorry, I'll give you a second to catch up. In 1600 Thales' observation would inspire British physician, natural philosopher and acknowledged father of electrical engineering, William Gilbert, to coin the term "electricus" from"elektron", the greek word for amber. Gilbert's work inspired many experiments and inventions but for for the sake of getting to the fun stuff more quickly I'm going to start with the invention of the electromagnet in 1825 which was what led to a series of discoveries that ultimately made electronic music possible.
The first electromagnet was demonstrated by British physicist, William Sturgeon who wrapped a seven ounce horseshoe shaped piece of iron with wire attached to a single battery and used it to lift a nine pound weight. This cleverness opened the doors to investigations of the induction phenomenon by Michael Faraday and Joseph Henry who both got their names permanently attached to things electrical. A henry is a unit of inductance and Faraday has a law and a shield
and a Sturgeon... Well, that's a fish.
Sturgeon's iron became magnetized because that's what happens when you run current through a wire wrapped around iron and you just have to accept that because physics can't really explain it. What Henry and Faraday discovered was that if you move a magnet through a coil (or a coil over a magnet) you can produce (induce) a current. This is the basis of microphone technology but that wouldn't come along until many years later.
What Henry did with his findings was to set up a demonstration whereby he sent a signal through a mile of cable that caused a magnet set up (a solenoid) to strike a bell on the other end. This caused several people to go, "Hmmm." and think in terms of communications possibilities and out of those several people, it was Samuel Morse who got the patent for the telegraph.
Mr. Morse' story leading up to the telegraph is worthy of a paragraph or two. Samuel was raised a strict Calvinist by a pastor father with the strict Calvinist name of Jedidiah. After a no-nonsense federalist childhood Samuel went off to Yale to study things religious, mathematical and uh, equine, as in the science of horses. Between these studious pursuits he also found time to attend lectures on the developing science of electricity.
He supported himself, as most students of math and science do, through painting. He was quite good at it and his work caught the eye of one Washington Allston who invited him to England to meet his friend Benjamin West. He stayed and studied with Allston for three years and by 1814 gained admittance to the Royal Academy.
He returned home, married and set up house in New Haven, Connecticut. He made a comfortable living as a painter, receiving many commissions and in 1825, received one from the City of New York to do a portrait of Gilbert du Motier, Marquis de Laffayette. He worked on it in Washington. D.C. and while there he received a letter from a horse messenger saying, "Your wife is convelescent." He quickly made for home but by the time he got there his wife was already dead and buried. This left him heartbroken but drove him to set aside his painting and figure out a means of communication beyond that of the horse and by 1847 he had the patent for the telegraph.
The telegraph evolved and was the it-girl of rapid communication until 1876 when the telephone was patented, it's invention also spurred by a man's love for the women in his life which I'll get to shortly. An interesting later development in telegraph technology (pursued and later abandoned by the soon to be mentioned inventor) was the use of multiple frequency transmission and the means of this found its way into a very early electronic keyboard called the Ondes Martenot. More on that later. Really. Let's stay focused.
Next up is Alexander Graham Bell, the recognized inventor of the telephone. He deserves special attention as it was the telephone that advanced the development of audio electronics more than anything else.
Bell was born in Edinburgh, Scotland to a college professor father who was a renowned elocutionist and mother who was an artist and pianist. His mother suffered hearing loss when he was 12 and this spawned an acute interest in Alexander for the subjects of speech and sound transmission. One of his earliest discoveries was that by speaking to his mother with his mouth close to her forehead she was able to decipher his speech through the vibrations this produced.
Besides his father, Alexander, his grandfather, also named Alexander, was also a renowned elocutionist and it was felt that young Alex would follow in the family biz. He was enrolled in The Royal High School but was a lousy student and left at the age of 15. That's right, kids; Alexander Graham Bell was a high school drop out. He did, however, excel in subjects that interested him and was very inventive from a young age.
One early invention he came up with was inspired by a friend's father, a flour mill owner/operator who asked the two boys to husk some wheat for him. Rather than suffer the laborious process of doing this by hand, Alexander came up with a device that did it for him and it was so effective it was kept in operation for several years. In thanks, the friend's father provided the boys with a workshop for further inventions.
He produced nothing of note in the workshop but later, working with his brother after seeing a speaking automaton, came up with one of his own after translating the German inventor's book on the subject. This involved the creation of a larynx, lips and skull and the boys managed to make it speak by forcing air through it with a bellows. What he learned in this process led him to teach the family terrier to get a steady growl going while he manipulated it's throat and mouth and he entertained the neighbors with what appeared to be a talking dog. This is how kids used to amuse themselves before radio came along and started rotting young minds.
inevitably, as the son of an elocutionist father who was also the son of said he developed his own keen interest in the subject and its application to the hearing impaired. He later gained a reputation as a teacher of the deaf and this ultimately led to his settling in America.
His interest in invention continued throughout his teaching years and he became focused on communication technology. His first efforts were towards tackling the challenge of the aforementioned multifrequency telegraph transmission but he was running in a crowded field. He was introduced in London to the work of German physicist, aesthetician, philosopher and all around super smart guy, Hermann Ludwig Ferdinand von Helmholtz. Helmholtz had experimented with tuning forks and electromagnets and had combined several forks of different frequencies to approximate the sound of human speech and this gave Bell the idea that he could actually transmit voice electrically.
His work was interrupted by a sad onslaught of tuberculosis which killed his two brothers and struck him as well. He moved to Canada under Doctor's orders and then to Boston where he had been invited by the Boston Board of Education to introduce his system of teaching speech at a new school for deaf mutes. He became very successful as a teacher, married one of his deaf students, Miss Mabel Hubbard and settled in Massachusets.
He resumed his experimenting and came across a device called a phonautograph at MIT which focused sound waves through a barrel and caused a membrane to vibrate. Brushes were attached to the membrane and the vibrations were etched onto smoke blackened glass. The result was called a phonautogram and in 2008, a computer program was developed that was able to play an etching that turned out to be an 1860 "recording" of "Au Claire de la Lune" which is considered to be the oldest existing record of a human voice.
Bell was inspired in his own unique way and had he not become known as the father of the telephone this next experiment could have made him the father of performance art had he exhibited it as such. Bell made himself a phonautograph but replaced the barrel and membrane with a real human ear, eardrum, hammer and stirrup and attached skull fragment. He talked, yelled and sang into the ear, and an attached straw etched the resulting vibrations onto a moving piece of smoked glass. In the glee of his success, he traumatized several of his friends and family with demonstrations of his macabre contraption.
The membrane was the method and now he knew he was close to realizing his invention but his backers, one of whom was the father of his future wife, thought his work on the telephone was a frivolous distraction and they were counting on his work on the telegraph for a return on their investment. He went ahead anyway and found success as he was burning his legs with acid he had just spilled. The historic and distressed words, "Mister Watson, come here. I want you." were heard via electrical transmission by the intended recipient through a device actually built by Watson.
Watson's device was a funnel that channeled and focused sound waves that would vibrate a diaphragm attached to a steel rod. The steel rod was connected to a wire attached to a receiver and the end not connected to the diaphragm sat in an acid and water mixture in which was also another wire connected to the receiver which completed a circuit. When the diaphragm vibrated, the rod going up and down in the acid water caused voltage fluctuations which caused the diaphragm of the receiver to vibrate and reproduce the sound.
Bell tweaked the design and came up with a device that wouldn't cause it's users chemical burns and after a few years of improvements, convincing people that they might actually have a use for the invention and a patent dispute (A man, Elisha Gray had filed a patent for a similar device only hours after Bell) the telephone finally got underway.
Thomas Edison actually came up with a better transmitter (and got into his own patent dispute) and Bell incorporated it. This was the carbon microphone and it stayed in use into the 1980's. Other improvements in the technology of sound quickly followed and eventually Bell Laboratories was formed so effort could be focused, funded and, of course, controlled by what was now AT&T.
Until 1966, the Labs' principal location was in The West Village in New york City in a building that is now called the Westbeth and serves as an artist residence. It was there that the modern study of electronic sound truly developed. Inventions there include: the condensor microphone, sound for picture, the improved vacuum tube, stereo, the transistor, the CD player and some 40,000 more. The cords used by electronic musicians (I've included electric guitarists here) were developed originally for phone use as were patch bays and patch cords which come from telephone switchboards. And it was the phone system, with its sound transmitting network of wires that made possible the not quite first electronic instrument, the Telharmonium which used the same Greek root word in its name as Bell used for his invention which translates to "at a distance."
In the next post we begin our exploration of the many marvelous contraptions devised for the production of music by means of electricity and introduce the very first electronic instrument.
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