The thing I never understood about the headphone jack and its disappearance: it doesn't need to be a jack. It need only be three contact points. You could have it on the outside rim of a phone and have a magnetic sheath hold the headphone pin to it. But I suppose it's not just about getting rid of the jack itself but also any DAC component? (But, isn't it doing that anyway for the speaker?)
The amplifier used for headphones is very different than what is used to drive a speaker. It's a totally different component. Also, remember, it's doing much more than just pumping audio out. Modern 3.5mm jacks on phones are 4 pin, generally, and you have to do the following (or, at least most of it):
* Detect if something is plugged in
* Detect if the thing plugged in is a 3 pin (stereo speakers), or 4 pin (stereo speakers, plus microphone)
* Detect what type of 4 pin configuration is connected (there are 2 standards, CTIA and OMTP)
* Detect button presses from attached headphones (volume up/down, pause/play)
* Detect the type of headphones connected (do I want to use the high impedance driver, or the low impedance driver)
And obviously: play stereo audio and record mono audio.
There's also some lesser used features that are sometimes supported over 3.5mm:
* Video output (!!)
* Antenna input, for use for FM radio
* Stereo audio input
* Optical out (not through 3.5mm TRRS, but it is at the end of the 3.5mm jack... Apple used to use these in their macbook pros)
The amplifier used for headphones is very different than what is used to drive a speaker. It's a totally different component.
It generally isn't, no. Looking at a teardown of the iPhone 5 for example (just the first phone I thought to check) there is a single Cirrus Logic class D amplifier chip that handles both the speaker and headphone outputs. I don't know of and cannot find any phones that have a dedicated amplifier chip for the headphone output although I'm sure one exists somewhere.
DAC is still there. Current iPhones can still use wired headphones, via the Lightning/headphone jack adapter. That adapter was included free in the box for a while. Now it's $9 or something.
With a 3.5mm jack you would have to carry wired earbuds, which would defeat the purpose...?
The thing I never understood about the headphone jack and its disappearance: it doesn't need to be a jack. It need only be three contact points. You could have it on the outside rim of a phone and have a magnetic sheath hold the headphone pin to it. But I suppose it's not just about getting rid of the jack itself but also any DAC component? (But, isn't it doing that anyway for the speaker?)
The amplifier used for headphones is very different than what is used to drive a speaker. It's a totally different component. Also, remember, it's doing much more than just pumping audio out. Modern 3.5mm jacks on phones are 4 pin, generally, and you have to do the following (or, at least most of it):
* Detect if something is plugged in
* Detect if the thing plugged in is a 3 pin (stereo speakers), or 4 pin (stereo speakers, plus microphone)
* Detect what type of 4 pin configuration is connected (there are 2 standards, CTIA and OMTP)
* Detect button presses from attached headphones (volume up/down, pause/play)
* Detect the type of headphones connected (do I want to use the high impedance driver, or the low impedance driver)
And obviously: play stereo audio and record mono audio.
There's also some lesser used features that are sometimes supported over 3.5mm:
* Video output (!!)
* Antenna input, for use for FM radio
* Stereo audio input
* Optical out (not through 3.5mm TRRS, but it is at the end of the 3.5mm jack... Apple used to use these in their macbook pros)
The amplifier used for headphones is very different than what is used to drive a speaker. It's a totally different component.
It generally isn't, no. Looking at a teardown of the iPhone 5 for example (just the first phone I thought to check) there is a single Cirrus Logic class D amplifier chip that handles both the speaker and headphone outputs. I don't know of and cannot find any phones that have a dedicated amplifier chip for the headphone output although I'm sure one exists somewhere.
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We have (had?) that. It's called USB-C Audio Accessory Mode.
DAC is still there. Current iPhones can still use wired headphones, via the Lightning/headphone jack adapter. That adapter was included free in the box for a while. Now it's $9 or something.
The adapter includes/is a DAC. The Lightning port is fully digital and cannot carry analog audio.
You just need a small adapter cable (1-2inch long) as on the iPhone, which is a fraction of your headphone.
You can get very very good audio with something like the UTWS5 and then you can use top end IEMs.