All-In-One Headphone

Listening music is one of the favorite things many people like to do. After more than a decade, It is still the best way to relax and feel good. It's now like a tradition to enjoy music whenever there is a festival or a party. The habit of Listening music is now flowing in the bloodstream of almost every people.

Nowadays many speakers are available from small size portable speakers to large size Home theater to earphones. But due to these wide varieties of music systems, These things seem to be a mess. Like if you are in a public place then you will use your earphone or headphone for listening music instead of speaker although you don't want yourself to seem weird in front of people by disturbing them. So all the Time we've to carry a headphone for your personal listening and a speaker to chill with your friends or with our families.

To overcome this mess, I came with an idea to create an All-In-One Headphone which is easy to carry and can be used as both as Headphone or speaker.

Here's the list of materials needed for the project! You can click on the link if you prefer to buy online(If available).

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Electronics and Materials:

- 2 x 3w speakers(4 cm)

- Mini PAM840 3 5V 2Channel Amplifier

- 4.5K Potentiometer

- 1 pair of Earpad

- USB Cable

- 3.5mm Male Jack

- 2 x Switches

- Wires

Tools:

- A 3D Printer

- Hot Glue gun

I think you have got an Idea that how our headphone works. But for ease, I am going to tell you how our All-In-One Headphone will work. Yes, If you guess that we will use the 3W speaker for both the sound driver in headphone and in speakers.

Our Headphone will be powered by a USB power supply and Its connectivity is by the aux cable. The changing of the speaker to headphone and again headphone to the speaker is controlled by a simple switch.

But here is a problem in this project which is that this Headphone is not created in real life by me either due to unavailability of a 3D printer. I don't own a 3D printer to make this project in real life. But you are here to bring this project in real life. I will try my best to explain everything needed to know to create this headphone by giving you right instruction.

Sound's good so let's start making it.

In this step, we just need to print our headphone body. Our whole Headphone body is created by a 3D printer. There are only three objects which we've to print but the number of time the object is to be print is different. The Link for the 3D design is given below.

- 2 x headphone v5

- 2 x headphone v6

- 1 x head v3

Now our Headphone Body is ready, so let's start with the Amplifier First. It will be placed on the wire, not in the baffle of headphone, So it would be easier for us by easily getting it in our hand to change volume level instead of keeping our hand on the baffle to do so. The work of the Amplifier here is simple as its name suggest - To amplify the sound. We don't have much work to do on amplifier circuit as that is created for exactly that type of work. On the circuit, it is labeled that which points are for which thing.

The point 1: in the picture has 3 points for aux cable wire. The L, R, and G denote left wire input, right wire input, and ground wire respectively of the aux cable. The Green, Red and copper color in the aux cable is left the wire, right wire and ground wire respectively.

The point 2: in the picture has 2 points for power input. The + and - denotes positive and negative respectively. I think this is the silliest thing I have told you about :-D. So, you just have to connect USB red and black wire on the + and - points.

The point 3: in the picture has 4 points for the connection of speakers. The 1 pair of the point is for Left speaker and the 2 pair of the point is for the second speaker. The Rout and Lout denote left and right output respectively. But you don't have to connect the speaker to the amplifier in this step.

Our work on amplifier circuit is done, Now we need to work on the main feature of this Headphone which makes it special and different from others. The ability of the speaker to be a headphone is based on a resistor and a switch combination. The above schematic diagram shows how the switch converts the speaker in a headphone.

If you focus on the diagram, you will notice that it is a simple switch which uses a combination of on and off to turn a speaker into a headphone or vice-versa. The current coming through the amplifier, first come in the switch and if the switch button is on the left side then it passes normally but when the switch button is on the right side then it passes through the resistor which reduces the current flowing in the wire and resulting in less volume. I think you are wondering why I used a potentiometer to the place of a resistor as in the parts list I have listed a 4.5k potentiometer and the reason behind it is that you will use a potentiometer on the place of resistor in the diagram to know the right value of the resistor to use in your circuit. Different people prefer loud music in their headphone and some medium amount of volume. For this, we will create the circuit using potentiometer first and then increase the music volume at full in the music player. Then it's upon you, that how much loud sound you want when it is on max volume in music player. When you will get your desired max volume after adjusting the potentiometer, measure the resistor value at that level of the potentiometer. Afterward, you are able to place a resistor of that resistance value in your circuit.

Also, you have to add the switch to both speakers wires that are Rout and Lout. But it feels uncomfortable to on and off both switch every single time when we want to convert it. So to resolve this issue we will first create this circuit for both speakers, not only for one because nowadays the songs use different sound on the basis of the left side and right side of the speaker to create music more realistic. So the current of Rout and Lout can be different and by connecting both speaker wire to one switch can create an irregularity in output and making music noisy and increase in distortion which we don't want. Using two switches for both speakers that can help to resolve this issue. And then we will use a super glue to join both switches buttons, so both can be on and off by just a single click instead of two.

Our amplifier and switch are ready to play the music. All we need to do is to assemble speaker onto the headphones left and right baffles and connect it to the circuit. So first, Mount the speaker onto the left and right baffles and put the top seat of baffles on it. And don't forget to take out the speaker wires from the holes of the baffles. Place the earpads on both the baffles, Well I don't think so, too tell you the steps on how to put earpad on it. Its simple enough to be done easily. Join the Headband of the headphone to both baffles. Place a Galvanized wire between the holes of baffle and headband.

Connect the speakers to the circuit and be sure to connect the same polarity of positive and negative of the speaker to the positive and negative of the circuit speaker output. It's very important.

Our work is now completed and you can use your headphone for both personal and for the group. Note:- be very careful when using it. If you are on loud music and use forget to convert it into the headphone then the loud music will directly hit your ear which will cause hearing loss. So be very careful and don't use it for fun to shock friend with suddenly a loud music.

After that enjoy your music, carry single headphone for both purposes. Well, you can also modify this headphone like by adding a rechargeable battery to it, making it wireless Bluetooth speaker, etc.

Post the photo if you made it and if you have any queries related to this project then you can ask me in comments, I will definitely try to help you to solve it :-D.

Bye......