- Crane, C. (n.d. ). SPEAKERS...IN A NUT SHELL. Retrieved from Center Point Audio website: http://www.centerpointaudio.com/howspeakerswork.aspx
This article focuses on how speakers work, frequency, how speakers make sound and also explains what a driver is. In summary, the website discusses that low frequency projects deep/low sounds which is known as Bass and high frequency projects high-pitched sounds which is known as Treble. It also mentions that speakers convert electrical signals to sound. By moving back and forth, the speaker increases and decreases the air pressure thus producing sound waves. The essentials of a speaker are the cone, suspension, magnet, voice coil and frame. The website provides an in-depth analysis of each essential. Drivers are speakers that voices a certain range of frequencies. There are three types of drivers: Woofers, Midrange and tweeters. Woofers produce low frequencies and are the largest of the drivers, midrange produce midrange frequencies and tweeters produce high frequencies.
- History of the Loudspeaker . (n.d.). Retrieved from https://www.voices.com/resources/articles/audio-recording-technology/history-of-the-loudspeaker
This source presents information on the history of speakers and how they have evolved overtime. In 1877, Ernst Siemens released a more advanced version of an electric loudspeaker. In 1898, Oliver Lodge developed a system of moving-coil however he was denied patents and thus could not sell his invention to record companies. In 1924, Chester W. Rice and Edwards W. Kellogg patented something called a direct radiator which used moving coil drivers. Later on, Walter H. Schottky invented the first ribbon loudspeaker that used electromagnets to energize coils. Then in the 1930s, loudspeakers began to combine drivers in order to make sound amplification better. Then in 1943, Altec introduced “Duplex” driver which improved sound quality and performance. Since then, there have been many improvements to both sound and quality and strength in loudspeakers.
- How are sounds created? (n.d.). Retrieved from http://www.dkfindout.com/uk/science/sound/how-are-sounds-created/
- How do speakers work? (n.d.). Retrieved from physics.org website: http://www.physics.org/article-questions.asp?id=54
This website provides information on how speakers work which also includes a video on how they work. This source explains that to convert an electrical signal into audible sound, speakers must contain an electromagnet which is a metal coil that creates a magnetic field when an electric current flows through it. It also explains that pulses of electricity are attracted to and repelled from the permanent magnet, vibrating back and forth. It also mentions that the frequency of the vibrations controls the pitch of the sound being created and the amplitude affects the volume.
- Loudspeaker Parts (n.d.). Retrieved from HH Electronics website: http://www.hhelectronics.com/technology/loudspeaker-parts-2
This source provides information of the parts (11 parts) that make up a speaker and in detail explains the function of that part. Starting from the end of the loudspeaker, the yoke affects the efficiency and stability of the magnet assembly and is places at the back of the loudspeaker. Next is the magnet which is the driving force. Followed by the front plate, this along with the yoke and magnet complete the magnetic circuit. Next comes the voice coil followed by the suspension which is an insignificant component which serves only to keep the voice coil in place. Then comes the cone which is the biggest factor determining the frequency response and overall sound. The surround joins the cone to the chassis and together controls the cone excursion. Lastly is the dust cap which keeps dust and dirt out of the voice coil.
- Woodford, C. (2016, February 23). Loudspeakers . Retrieved from http://www.explainthatstuff.com/loudspeakers.html
This source provides information on what loudspeakers are, how they turn electricity into sound, the parts of a loudspeaker and its functions. The author, Chris Woodford also talks about how to make your speakers sound better, how electrostatic speakers work and why bigger and more powerful isn’t always louder. Woodford explains that sound is created when things (the cone) vibrates and pumps sound out into the air. He also discusses about the 12 parts of a loudspeaker and the functions of each part. These parts include cone, dust cap, surround, basket, spider, magnet, bottom plate, pole piece, voice coil, former, top plate and cables.
- Speakers. (n.d.). Retrieved from https://physics.wustl.edu/introphys/Phys117_118/Lab_Manual/Experiments/Speakers_SU13.pdf
This pdf is an excellent source as it contains information about speakers. It goes into detail about the creation of sound by speakers, how speakers work, how to build a speaker and contains many experiments which anyone can conduct alone. In this pdf it also states the importance of the diaphragm and voice coil. This pdf also provides lots of diagrams the parts of the speakers, how speakers work, sound waves etc.
- Miller, J. (n.d.). Audio Speakers and Relation to Physics . Retrieved from http://www2.hesston.edu/Physics/AudioSpeakers/PHYSICS.HTM
This website focuses on how speakers relate to physics and how audio speakers work. It also discusses about different drivers for speakers such as woofer, tweeter and midrange. It also contains great advice about which speaker to buy, how to set it ip and goes into detail about the efficiency of speakers (sensitivity). Miller has discussed quite a lot in this article which is ideal for people who need help to identify how physics relate to speakers.
- Ellis, D. (2012, September). Re: Why do speakers only seem to have round diaphragms? [Web log comment]. Retrieved from http://www.soundonsound.com/sos/sep12/articles/qanda-0912-4.htm
In this post, Darren Ellis responded to a question to “why speakers only seem to have round diaphragms.” Ellis stated that speakers have a round shaped cone because loudspeakers physically have to move a lot of air which means the diaphragm has to move a relatively long way and thus requires a very flexible surround. Achieving that in a non-circular shape is quite difficult as the cornered surround would introduce many problems. Darren Ellis also mentioned that the main idea of non-round diaphragm is to minimize and control the natural membrane resonances where a round diaphragm has a strong single primary resonance.
- Crowhurst, N. (n.d.). The Speaker Diaphragm. Retrieved from http://www.vias.org/crowhurstba/crowhurst_basic_audio_vol1_044.html
This article written by N.H. Crowhurst is an excellent article which discusses the importance of a diaphragm and its shape. The author talks about how big should the cone be and states that it depends on the wavelength of the sounds we want, if the size of the diaphragm is smaller than a wavelength then the air tends to run round the edges instead of going back and forth with the diaphragm. Whereas if the diaphragm was large compared to the wavelength, the air will not have time to dodge around it during the passage of each wave. The author also talks about the relationship of cone size and frequency, he states that a large diaphragm is required for the lower frequencies, while a smaller one will serve for the high frequencies.