Bluetooth or wireless technology is not a new entry in the tech world. But it has revolutionized the concept of headphones even among the common people. It is quite natural for a normal person to wonder how do Bluetooth headphones work?
The working of a wired earphone is not a “Nolan’s thing” because there we have a cable to carry the audio signal. But here, we don’t have any such cable to take the current that carries audio signals from a mobile phone to a headset.
How are Bluetooth devices connected to each other and form a Piconet for transferring data without a cable? Here we clear all your doubts about how does a Bluetooth headset work.
What is a Wireless Headphone?
Before we take you deep into the science behind wireless earphones, we believe it is essential to tell what are Bluetooth headsets. They are a kind of headset without any cables to connect your audio source and headphone.
Here the signal transfer occurs through radio or infrared waves instead of wires. Whether you are using True Wireless Stereo (TWS) earbuds, wireless headphones, headset, or earphones, the working principle is the same.
We have already discussed the types of headphones. Neckband, wireless headphones, and Truly Wireless earbuds are three predominant Bluetooth models.
You can use them to connect with different devices like smartphones, smart TV, gaming console, laptop, and other electronic items.
How do Bluetooth Headphones work?
The working of wireless headphones is similar to wired types except for the bridge between audio source and headset.
When you activate the Bluetooth, it creates a piconet, and a communication channel is established; we call it pairing. Now they can transfer information between them.
When you want to hear a song through a paired wireless headset first, the smartphone takes the audio information from the flash storage chip. Then it is given to the phone’s storage.
There it will be converted into digital signals as corresponding numbers. The length and complexity of the digital depend on the audio details.
The smartphone then sorts and arrange them into digital packets and send them to the headphone through the radio waves. This process will typically be based on Bluetooth specification.
Then the headphone receiver arranges and sorts it back to the initial numbers. It will then be given to the audio codec, a computer program that decompresses digital audio data into a corresponding audio file.
The audio codec converts it into an analog waveform because headphone parts like coil and magnet can not read the digital data directly.
Then this waveform fed into the voice coil, and it moves up and down based on the signal. Then as we all know, this vibration moves the air around it and produces the corresponding audio output.
This is the basic Bluetooth earphone working principle.
The majority of the wireless earphones and TWS earbuds work on Bluetooth version 4 or the latest version 5.1. These two versions ensure approximately 10 meters of drop-free and crystal clear communication.
Their range is unaffected by wind and other small hindrances such as partitions.
Wireless technology uses radio or infrared frequency waves to transfer sound signals. But the Bluetooth feature depends mainly on radio waves from 2.4 GHz to 2.48 GHz, which means that they are moving at a speed of 2.4 to 2.48 billion waves per second.
Even though that handles such a massive amount of data, the power consumption is too low in the range of 1 milliwatt or so.
The two main things that are mandatory to establish wireless connectivity are a transmitter and a receiver. The audio source such as mobile phones, smart TVs, etc., contains a transmitter with an inbuilt chip for pairing with nearby devices with Bluetooth technology.
But that is not enough; headphones need something to receive the audio signals. The radio receivers receive them and act as a transducer.
You may know transducers as devices that convert energy from one form to another. They retrieve sound from the signal.
You have to press the power button on the wireless device to activate the Bluetooth mode. Then only it can pair with a nearby device, and that’s why your device needs an external power source like a Li-ion battery.
There are two types one is Bluetooth Low Energy (BLE) and another is Bluetooth Enhanced Data Rate (EDR). Studies show that BLE is more efficient in the transfer of data.
What is an Audio CoDec?
It is the abbreviation of coding and decoding. Even though it can be software or hardware, wireless Bluetooth exclusively uses specialized software.
Based on the requirement, it compresses or decompresses data; in other words, it converts data from one form to another. Here, the audio codec converts digital audio data into voice coil-compatible analog waveforms (or ~sinusoidal waveforms.
In simple terms, it enables Digital to Analogue Conversion (DAC). It can also work in the inverse direction, i.e., ADC.
Wireless Headphones and Health Concerns
Two factors we consider while using electronic devices are comfort and health problems. In addition to hearing safety, Bluetooth device users are also doubtful about radiation hazards.
In a positive sense, the hazardous non-ionizing radiation from a wireless headset is far less than that from a smartphone. On the other hand, it is quite sorry to say that health issues associated with Bluetooth devices are yet to study deeply.
The approach from Federal Communication Commission implies they are safe.
We hope this article helps you to understand how do Bluetooth headphones work. Most of the headphones have a frequency response of 20 Hz to 20 kHz because this is the audible limit of a human ear.
Bluetooth version 4 and above supports fast data transfer and quick connectivity.
If you have any comments, put it below.