{"id":6810,"date":"2022-12-16T09:47:52","date_gmt":"2022-12-16T14:47:52","guid":{"rendered":"https:\/\/audioapartment.com\/?p=6810"},"modified":"2023-04-21T09:46:55","modified_gmt":"2023-04-21T13:46:55","slug":"how-are-headphones-powered","status":"publish","type":"post","link":"https:\/\/audioapartment.com\/instruments-and-equipment\/how-are-headphones-powered\/","title":{"rendered":"How Do Headphones Get Power? (Answered)"},"content":{"rendered":"\n

As a music producer, I know that a good pair of headphones can be the difference between a hit song and a dud. But have you ever stopped to think about how your headphones actually get their power<\/strong>? It’s not like they’re plugged into a wall like your trusty old boom box (remember those?).<\/p>\n\n\n\n

In this article, I’ll explain the ins and outs of headphone power and hopefully drop a few puns along the way (because, let’s face it, “head” and “power” are just begging for a good pun-ch line).<\/p>\n\n\n\n

How do headphones get power? <\/strong>Headphones typically get their power from an amplifier. The amplifier boosts the signal from the audio source, providing the power needed to drive the headphones. In some cases, headphones may also have their own built-in amplifiers, allowing them to be powered directly from the audio source.<\/p>\n\n\n\n

How do headphones work?<\/h2>\n\n\n\n

Headphones work by converting electrical signals into sound waves. When an audio source such as a smartphone or MP3 player sends a signal to the headphones, it is received by a small device called a transducer. <\/p>\n\n\n\n

The transducer, also known as a driver, converts the electrical signal into mechanical energy, causing a small membrane called a diaphragm to vibrate. This vibration creates sound waves, which are then directed into the ear by the headphones’ speaker cups.<\/p>\n\n\n\n

In order for the transducer to create sufficient vibration to produce sound, it needs a certain amount of power. In the case of wired headphones, this power is provided by the audio source<\/strong>, which sends the electrical signal to the headphones through a wire. <\/p>\n\n\n\n

Wireless headphones, on the other hand, use a built-in amplifier to boost the power of the signal received from the audio source. This amplified signal is then used to drive the transducer and produce sound.<\/p>\n\n\n\n

Why do some headphones not need power?<\/h2>\n\n\n\n

Some headphones do not need external power because they have their own built-in amplifier. This allows them to be powered directly from the audio source without the need for an external amplifier. In general, headphones with built-in amplifiers are larger and more advanced and are designed to produce high-quality audio<\/a> without the need for external amplification.<\/p>\n\n\n\n

To set the stage, I should mention that the vast majority of headphones do not need an external power source<\/strong>. This is because almost all headphones employ dynamic drivers<\/a> (moving-coil dynamic, to be more specific). The dynamic transducers in headphones do this by inducing a magnetic field over the audio signal.<\/p>\n\n\n\n

The moving-coil driver’s construction is straightforward and deserving of an explanation. For clarity, let’s take a look at a simplified cross-sectional schematic of a moving-coil headphone driver. Electrical conduction occurs in the voice coil (typically made of copper). The coil has two lead wires attached to it, one at each end, which complete a circuit between the audio source and the headphones’ earpieces.<\/p>\n\n\n\n

The magnetic field created by the coil changes when an audio signal (alternating current) moves across it. <\/p><\/blockquote><\/figure>\n\n\n\n

The coil is dangling from a cylinder-shaped opening in an irregularly shaped magnet. The mechanism that suspends it is a moving diaphragm to which it is fastened. The magnetic field created by the coil changes when an audio signal (alternating current) moves across it. The magnetic field provided by the magnets and the induced field has an effect on one another.<\/p>\n\n\n\n

Because of this, the hung coil oscillates slightly back and forth from its equilibrium position. The diaphragm moves in tandem with the coil. Sound is created as the diaphragm contracts and expands, forcing air in and out of its surrounding space. It’s clear that the audio data is being faithfully reproduced as sound waves by the moving-coil dynamic driver, and it’s doing so without any additional power.<\/p>\n\n\n\n

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Image of a man holding black headphones. Source: paloma clarice, pexels<\/figcaption><\/figure>\n\n\n\n

The role of amplification in powering headphones<\/h2>\n\n\n\n

Amplification plays a crucial role in powering headphones. In the case of wired headphones, the audio source provides the electrical signal that is sent to the headphones through a wire. However, this signal may not have sufficient power to drive the transducer in the headphones and produce sound. <\/p>\n\n\n\n

In order to increase the power of the signal, an amplifier is used. A headphone amplifier is a relatively low-powered amplifier that is specifically designed for on-ear or in-ear listening devices. It can be integrated into the device or be a standalone device. The amplifier boosts the signal from the audio source<\/strong>, providing the power needed to drive the transducer and produce sound.<\/p>\n\n\n\n

The purpose of using a headphone amplifier is to improve the sound quality of the headphones by providing more power to the headphones, which can improve the overall soundstage, clarity, and dynamic range. In some cases, a headphone amplifier can also drive higher-impedance headphones that a device’s built-in amplifier may not be able to drive properly.<\/p>\n\n\n\n

Wireless headphones, on the other hand, use a built-in amplifier to boost the power of the signal received from the audio source. This amplified signal is then used to drive the transducer and produce sound.<\/p>\n\n\n\n

If you want even more tips and insights, watch this video called “Can you plug headphones directly into an amplifier?”<\/em> from the PS Audio YouTube channel.<\/p>\n\n\n\n

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