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In this lesson we're going to talk about the audio amplifiers

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In iPhone, master audio is mainly responsible for audio signal conversion

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Audio amplifiers are mainly used to amplify audio signals

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By amplifying the audio signal, you can make the horn sound even louder

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In early mainboards, there was only one audio amplifier

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In iPhone 7 and above, there will be two audio amplifiers,

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one connected to the receiver

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So when we play a song,

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the speaker on the receiver will make a loud noise

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There's also a chip that connects to the bottom speaker

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So when we play,

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the speakers at the bottom can also make a lot of noise

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The models before iPhone 7,

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such as the iPhone 6, had only one audio amplifier

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It's mainly connected to the bottom speaker

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When we play a song,

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the one with only the speakers makes a loud sound,

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and the one at the top is silent

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This audio amplifier is also called by many names

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The one connected to the position of the receiver is also called the receiver power amplifier,

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and the one connected to the speaker is also called the speaker power amplifier

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But some people also called small audio,

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in fact, refers to the audio amplifier,

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its main function is to amplify the audio signal

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When the audio amplifier is damaged,

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it will cause no sound, or low sound

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In the mainboard, the earphone amplifier,

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the speaker amplifier, and the vibration chip

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These three chip models are the same,

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and after damage, they can be exchanged

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Audio amplifier is generally rectangular,

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its chip surface logo is 338s beginning

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But it will be much smaller than the main audio

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Next, let's go to the mainboard to learn about the audio amplifier

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Audio amplifiers from iPhone 7 and up, it will have two

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On top of the CPU here is a black, glued surface,

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and it's a receiver power amplifier,

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which is actually an audio power amplifier

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Under the hard drive here are two chips,

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and they're the same model

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One is the audio amplifier, also known as the speaker amplifier,

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and the other is the vibration chip, and they can be interchangeable

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This mainboard is a XR model

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It has two audio amplifiers

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The first one directly above the CPU is the earphone amplifier

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Under the WIFI chip, we can see two glass chips,

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one is the vibration chip,

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the other is the speaker amplifier chip

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The models of these three chips are the same and can be interchangeable

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So that's it for this lesson