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USB-IF Publishes Audio Over USB Type-C Specifications (anandtech.com)
An anonymous reader quotes a report from AnandTech: The USB Implementers Forum this week published the USB Audio Device Class 3.0 (direct download) specification, which standardizes audio over USB Type-C interface. The new spec enables hardware makers to eliminate traditional 3.5mm mini-jacks from their devices and use USB-C ports to connect headsets and other audio equipment. Makers of peripherals can also build their audio solutions, which use USB-C instead of traditional analog connectors. Developers of the standard hope that elimination of mini-jacks will help to make devices slimmer, smarter and less power hungry. As reported, the USB Audio Device Class 3.0 specification supports both analog and digital audio. Analog audio is easy to implement and it does not impact data transfers and other functionality of USB-C cables since it uses the two secondary bus (SBU) pins. The USB ADC 3.0 defines minimum interoperability across analog and digital devices in order to avoid confusion of end-users because of incompatibility. In fact, all ADC 3.0-compliant hosts should support the so-called headset adapter devices, which allow to connect analog headsets to USB-C. However, digital audio is one of the primary reasons why companies like Intel wanted to develop the USB-C audio tech on the first place, hence, expect them to promote it. According to the USB ADC 3.0 standard, digital USB-C headphones will feature special multi-function processing units (MPUs), which will, to a large degree, define the feature set and quality of headsets. The MPUs will handle host and sink synchronization (this is a key challenge for digital USB audio), digital-to-analog conversion, low-latency active noise cancellation, acoustic echo canceling, equalization, microphone automatic gain control, volume control and others. Such chips will also contain programmable amplifiers and pre-amplifiers, which are currently located inside devices. Besides, USB ADC 3.0-compatible MPUs will also support USB Audio Type-III and Type-IV formats (the latest compressed formats), but will retain compatibility with formats supported by ADC 1.0 and 2.0. Finally, among the mandated things set to be supported by USB-C Audio devices are new Power Domains (allows devices to put certain domains in sleep mode when not in use) as well as BADD (basic audio device definition) 3.0 features for saving power and simplified discovery and management of various audio equipment (each type of devices has its own BADD profile).
DRM...
I'm sitting here looking at my nice Nexus 5x phone, that has a perfectly good 3.5mm jack on it. If I lose my earbuds, I can walk into most any store and buy absolutely adequate replacements for $10 or less. The Nexus 5 is already so thin that it felt funny in my hand and I had to buy a case for it that makes it thicker.
You think USB-C headphones that "will feature special multi-function processing units (MPUs)" are ever going to be $10?
You are welcome on my lawn.
Apple: "We're removing the USB jack from our phones. Wait, we never had one? Okay, FINE, we'll remove the Lightning connector, wiseass!"
Just cruising through this digital world at 33 1/3 rpm...
It's about DRM
from here:
http://ww1.microchip.com/downl...
"The SBU wires are lower speed signal wires that is allocated for Alternate Mode use only. USB Power Delivery is required for Alternate Mode negotiation before these pins may be used for any purpose".
Doesn't sound like headphone power-level or analog to me.
Anybody know the mean time between failure for these plugs (The micro ones)?
I've only had a headphone jack fail once, due to some pocket lint getting in the hole, which I was able to remove.
I've gone through a number of cords and a few devices due to failure of the cord, failure of the female plug, or the female plug becoming so fatigued the solder broke attaching it to the PCB.
The 3.5mm jack is pretty solid when it comes to abuse. I've accidentally broken off USB connectors several times.
It opens a lot of possibilities. Standardised docks, single-connection car charging+audio, powered Bluetooth receivers, that sort of thing. It's a great option to add to our toolset.
But only as an option - not if it means removing the headphone jack too. If it catches on, everyone starts using USB headphones and audio jacks fall out of favour, then we can talk, but it's insane to remove such a popular connector while it's still so wisely-used.
Why would anyone engrave "Elbereth"?
"Developers of the standard hope that elimination of mini-jacks will help to make devices slimmer, smarter and less power hungry."
Less power hungry? Sounds like bullshit. Could someone explain how?
Because of the lack of a 3.5mm standard jack, more users will choose NOT to play music on their devices. This results in less usage of the audio amplifiers that feed signal to earbuds and headphones, resulting in less power use overall. ;-)
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
No really, I'm quite happy with my 3.5" port which is on my PC, PS4 controller, ipad (currently....) old spare phone, etc.
Good, enjoy your 88.9 mm ports then, I personally prefer the 3.5 mm standard.
Innovative my ass. Nokia and Sony Ericsson were combining everything in the same port years before: Pop-Port, FastPort.
And guess what it sucked and having a separate 3.5mm audio jack was considered a huge improvement.
Back then it was considered to be a way to force people to buy their accessories and a cash grab. Now Apple calls it "courage". Hah.
No mention of vorbis, flac, alac or opus. Great, isn't it?
PCM_IEC60958
AC-3
MPEG-1_Layer1
MPEG-1_Layer2/3 or MPEG-2_NOEXT
MPEG-2_EXT
MPEG-2_AAC_ADTS
MPEG-2_Layer1_LS
MPEG-2_Layer2/3_LS
DTS-I
DTS-II
DTS-III
ATRAC
ATRAC2/3
WMA
E-AC-3
MAT
DTS-IV
MPEG-4_HE_AAC
MPEG-4_HE_AAC_V2
MPEG-4_AAC_LC
DRA
MPEG-4_HE_AAC_SURROUND
MPEG-4_AAC_LC_SURROUND
MPEG-H_3D_AUDIO
AC4
MPEG-4_AAC_ELD
I'll concede that the "slimmer" claim is realistic, given that two connectors take less space than one. But in a time when phones are getting larger and larger, I don't think this is going to solve anyone's problem.
The claim that devices will be "smarter", instead, can be scary. USB devices can be flaky at times because of the complexity of the protocol. On top on that, I've had some mixed experiences with USB-audio class devices in particular. And if the analog audio option of this new connector isn't mandatory, we'll end up buying earphones that sometimes work, sometimes don't, depending on an invisible capability of the device. Not to mention that application software can prevent the use of the analog outputs for DRM reasons, as it happens today for the video outputs.
Now before anyone freaks out, keep in mind that there is nothing in the Audio over USB-C spec that requires the device that implements it to not have a headphone jack. Its totally legit for a phone to support this spec and have a headphone jack. In fact, I suspect that most vendors will probably go this route.
Being able to plug your phone in to a single USB-C connector on your car or stereo and have it charge the battery and play music using 1 wire is a nice feature.
In reading the summary I got the impression that they were going to use the low speed data lines on the USB-C connector as analog output lines. That would make more sense to me than defining some new audio device standard. I thought the USB 2 spec contained enough audio device standards to satisfy any kind of headphone setup people might use on a phone, music player, computer, or whatever else someone might expect to find a USB-C port. With USB 2 data pins being a common and required part of any USB-C alternate mode I'd think that creating a device capable of plugging into a USB-C port and providing audio input and/or output would be trivial and essentially a solved problem. USB 2 is certainly capable, as far as I can tell, of providing multiple audio channels with high fidelity without running into issues of bandwidth or power limits. Perhaps I'm missing an important detail.
I never was a big fan of USB. I thought the spec always was second best to competition like FireWire. The lack of peer to peer was a big problem for me. The confusing connectors are such a problem that it's become a joke that nearly everyone in the world would understand, if there is a place in the world with cell phone coverage then people understand the need to flip a USB connector over 3 or 4 times before being able to plug them in right. Power limitations were also a problem from the start, which lead to many interesting non-standard means to address it. USB 3.1 and the USB-C connector fixed a lot of these problems which basically came down to, IMHO, reinventing FireWire.
While the USB people are fixing the problems with the past versions with USB 3 I have to wonder if they aren't creating more problems with their over use of the "alt mode" feature. With so many optional alternate modes I believe that there may be a problem with consumers getting confused with the capability of the ports on their device and what kind of cables, devices, and adapters they need to do what they want to do. There are three different video alternate modes for USB-C right now, DisplayPort/Thunderbolt, MHL, and HDMI/DVI. I can just imagine the frustration people could have in trying to find the right cable and/or display to connect to a device with a USB-C port.
If the USB people are going to make the audio connection capabilities as complicated as the video connection capabilities then they might be making people avoid USB-C because it offers TOO MUCH capability since people won't be sure how to use it. Ports like PS/2, eSATA, VGA, DVI, HDMI, Ethernet, and so on are simple to use and understand because they do one thing, and do them quite well. Trying to stack too much into one port might be great for the computer geek but not so much for a large portion of the public that just want things to work.
I am armed because I am free. I am free because I am armed.
USB 3.1 and the USB-C connector fixed a lot of these problems which basically came down to, IMHO, reinventing FireWire.
So in essence, the current spec is Firewire + USB 2.0 bolted together, because it still needs the old set of pins to stay compatible. It's "universal" because when you glue enough different physical standards together, there's a chance that one of them will fit.
Escher was the first MC and Giger invented the HR department.