You might not know it, but speakers have magnets. Not only that, but they're also the most important part of your sound system.
Speakers have magnets because they make it possible to create sounds and for us to hear music. Connecting an amplifier to a speaker produces an electric current that travels through the wire on the other. It creates an electromagnetic field around the cone of your speaker driver, which in turn causes it to vibrate. The vibration causes air molecules to move around inside your room or car, and this movement is what we perceive as sound.
What Is a Speaker Magnet?
A speaker magnet is a permanent magnet that's used in loudspeakers. It's responsible for producing the magnetic field that causes the voice coil, a coil of wire wrapped around an iron core, to move back and forth as it's energized by electricity. This movement creates sound waves in the air and produces music!
There are different types of speakers: planar, horn, and waveguide.
- Planar speakers use a flat surface to produce sound waves. They're often used in high-end audio equipment because they can deliver high-quality sound reasonably.
- Horn speakers use a long tube-like shape to produce sound waves. Horns have been around for centuries, but only recently have they become popular again due to their ability to produce very loud sounds without much power.
- Waveguide speakers use a curved surface that helps focus the soundwaves into a beam so they can be directed more easily at the listener. This is particularly useful for small devices like phones and tablets, where space is at a premium.
The shapes and sizes of speakers may change but the one constant in all of them is the magnet.
How Does A Speaker Use Magnets?
The magnets are what make the speaker work. They are made of neodymium, which is an element that is very powerful and rare. The magnet is attached to the speaker cone, which pushes the air around it, creating sound. Without a magnet, there would be no sound at all!
Speakers also have a coil that creates electricity when it moves back and forth. The coil is wrapped around a permanent magnet, and this causes it to move back and forth when you turn on music. The coil moves back and forth thousands of times per second, creating electricity.
Magnets are used in speakers to create a magnetic field. The magnetic field is produced by copper wire coils wrapped around a central magnet. The speaker's voice coil is attached to the moving diaphragm and moves in response to electrical signals generated by an amplifier.
The magnet creates a magnetic field that acts on the diaphragm, causing it to move back and forth, creating sound waves. As the voice coil moves through this magnetic field, it creates an electrical current amplified by the amplifier, producing sound waves from your music source.
Basically, the speaker has two magnets, which produce a magnetic field when turned on. One magnet is stationary while the other moves back and forth, producing an electrical current that creates a magnetic field in its path. The moving magnet produces an electromagnetic force that attracts iron particles from within its reach.
How Strong Are Magnets in Speakers?
Magnetic fields are measured in units called teslas (T). One tesla is equal to one thousand gausses. One gauss equals 10-4 tesla or 10-4 microtesla (µT).
The strength of a speaker's magnet depends on how much power it can handle before it distorts or stops working altogether. A typical speaker might have a power rating of 50 watts, meaning it can handle up to 50 watts before distorting or breaking down completely. The higher this rating, however, the more expensive it will be.
- Speakers with a 1.0 T magnet will be relatively weak compared to speakers with a 4.0 T magnet.
- Speakers with a 4.0 T magnet can produce higher volume levels than speakers with a 1.0 T magnet.
- Speakers with an 8″ driver and 4″ woofer have more moving mass than speakers with smaller drivers and woofers; therefore, they require more power from their amplifiers to achieve similar volume levels as the smaller speaker system.
How Can You Use Magnets in Old Speakers for Magnet Fishing?
There are many ways to do this, but the simplest method involves finding an old speaker (that does not work) and extracting the magnet from it. Remember some of those old speakers built in wooden boxes ? Find them. The bigger the speaker the more powerful your magnet.
Carefully dismantle the speaker box or use a box cutter to remove the magnet from the speaker. The round/circle object is usually where the magnet is located. The speaker will usually be sealed with adhesive plaster, strip off all the foam material from the speaker.
Once you have the speaker part out, the magnet should be located on the back part.
You can then attach this speaker cone and magnet to your rope using a knot or the carabiner clip and start using it for magnet fishing.
If you want to go a step further and remove the actual neodymium magnet from the speaker cone, see the video below,
Neodymium Magnet in Speakers – https://www.chem.tamu.edu/rgroup/marcetta/chem362/HW/2017%20Student%20Posters/Neodymium%20Magnet%20in%20a%20Speaker.pdf