speaker anatomy

Understanding Outdoor Speaker Anatomy – Noisylabs


Speaker Anatomy


speaker transducer

Think of a transducer as a energy converter. It takes one type of energy and converts it into a type of energy we can hear. Here are a couple of examples of transducers.

One transducer related to sound is the microphone.

It takes a physical form of energy (electricity) and turns it into sound waves for us to hear.

Another example is a food scale. It takes the pressure of whatever you put on the scale and converts it into something you can read.

There are 2 types of transducers. The first one is called "input", and the other type is called "output."

Outdoor speakers are a output transducer. They take electric energy and turn it into physical energy. The input transducer does the opposite. It takes physical energy and turns it into information.

The problem with transducers is their efficiency. When energy has to go through conversion, it loses some of its power. If you can figure out this efficiency problem, then you'll have more power.


speaker anatomy

The purpose of the magnets is to create an electromagnetic field. This a huge part of a speaker anatomy and its ecosystem.

This is where electric waves pass through. For the electromagnetic field to work out, you need 2 magnets in the speaker. You need the permanent magnet and the electromagnet which we've already talked about. 

Permanent magnets are fixed in place while electromagnets are attached to a voice coil which allows it to be flexible. 

The permanent magnet's role is like a wall. It's used to ricochet sound waves into the cone. On the flip side is the electromagnet which handles the electric waves through its coil.

The electromagnet's flexibility allows it to vibrate back and forth for the electric waves.

To summarize, both magnets need each other to produce sound. Both of them are there to create an electromagnetic field which electricity passes through to create sound waves.


speaker anatomy

There are 2 plates in a speaker.

You have the bottom plate and the top plate. Both plates are made from soft iron.

Their responsibility is similar to a cop directing traffic. Since both plates are conducive to magnets, the plates direct their magnetic energy towards the voice coil. 

Speaker plates are made up of different fabrics. Some plates are made with paper, and others are made with foam. Similar to cones, each fabric has there pros/cons.

Dust Cap

speaker anatomy

You can find the dust cap in the middle of the cone. It looks like a dimple when you look at the exterior of the speaker.

This piece has a smaller responsibility compared to the rest. Its duty is to prevent getting any debris inside the speaker.

If you see how all the components fit together, you'll see the dust cap covering the pole piece and magnet from getting any debris on them.

Dust comes from a variety of objects. It all depends on the environment.

Assuming you're speaker is in a residential area, there are a number of reasons your speaker will collect dust.

A couple of reasons are dead skin particles and other objects collecting dust around it. This in turn gives it more dust. The problem with dust is it gets into the circuitry flow of electricity affecting the whole process.

Voice Coil

speaker anatomy

Remember when we talked about the magnetic field?

Have you ever thought of where the magnetic field went?

Well, the magnetic field created by the magnets wraps itself around this coil. This magnetic field combined with electricity causes voice coils to burn. And when the polarity of attraction and repel happens, the coil follows suit.

The moving coil pulls and presses the cone creating the vibrations needed for sound waves. 


speaker anatomy

Think of the spider as the set crew of a movie set. 

They don't get the main credit like the magnets, but they should get their notice.

The responsibility of the spider is to connect the coil and the spider. 

It lets the coil flow freely but it also holds it in position. This position is similar to a yo-yo. It's stabilized when rolled up, but you can move it back and forth when you want to.

Same concept applies to the spider. It allows flexibility in movement, but keeps it in place.


speaker anatomy

The spider allows the coil to move back and forth. For the surround, it does the complete opposite.

A ring allows the cone to move back and forth but it doesn't let it sway side to side. Both the spider and surround work together to assist the voice coil in accomplishing its job. 

Think of the surround as a frame.

Flex Wires And Wire Terminals

speaker anatomy

Think of this as the tunnel for electrical current.

The flex wires and wire terminals move electrical current from the amplifier to the voice coil.

It's the bridge for the voice coil to do its work.


speaker anatomy

A frame is the easiest to remember out of all these parts.

It holds everything together just like a picture frame. It's also known as a basket, meaning, it holds everything.

This basket includes the voice coil and the cone, but there are other components it contains.


speaker anatomy

A cone, also called a diaphragm is made up of different material depending on the objective.

A loudspeaker's cone can be made up of paper, metal, or plastic. All of them have their pros and cons. We've even covered different types of cones to let you know what you're getting into.

When the coil from the magnet goes back and forth, this forces the cone to pump sound into the air. 

There are 2 parts to a cone. You have the outer and inner part. 

The outer part of the cone is connected to the outer part of the metal rim of the loudspeaker.

Inside of the cone is the inner part. This is where the voice coil connects to the inner part of the cone. Behind the inner part of the cone lies the permanent magnet which sits in a fixed position.

One aspect worth noting with cones is their size. If you have big cones, then it's more suited for lower frequencies which means heavier bass. Smaller cones, also known as tweeters, are meant for higher frequencies.

And when it comes to smaller cones, there are different types of tweeters. It's important to know the differences.

How Does Everything Come Together?

speaker anatomy

Now that we've covered the fundamentals of speakers, let's put everything in perspective.

It all starts with electricity. Once the electricity enters, it's the job of the transducer (speaker) to convert the energy into sound waves.

The magnets are up next. There are 2 magnets which play a role. The permanent magnet and the electromagnet. One is in a fixed position while the other one moves back and forth.

Their whole purpose is to create a magnetic field.

But what directs the electric current towards the voice coil?

Both, the top plate and bottom plate direct current towards the voice coil.

Once the magnetic field creates polarity for the coil, the coil pulls and presses on the cone to create the vibrations needed for sound waves.

All of this is also possible due to the flex wires. They help electricity travel.

These are the mechanics of sound forming.

The frame, dust cap, spider, and more are the supporting cast. They're important for functional purposes but they're not as involved as the other components.

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