Can Tablet PC (android) drive an USB DAC?

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If Jellybean supports it then the googles nexus 7 tablet, set for full release in ~2 weeks, should support it.

Android support is fairly poor from some manufactures though, with lots not even up to ICS 4.0 yet.

I don't see windows RT as replacing Android however. Android will still rule the cheap tablet market, windows RT comes with a fairly hefty license fee and this will push RT tablets into the realm of the premium products.

Things like the nexus and the kindle fire will still run android and these are likely to become the two top selling tablets at the bottom end of the market.

Windows RT will come in at a higher price point and that will most likely be the choice of operating system for most people as it will have microsofts generally good support, so no worries about being kept up to date. Of course windows RT wont run any native windows programs, so in terms of what an RT tablet will give you over an android one...that's basically down to their associated app stores.

Pay a bit more however and you can get windows 8 on a tablet and this will run windows programs.

I sort of see windows RT as being a bit of a black sheep, most RT capable tablets will run windows 8, the only real difference being that they need the new intel x86 tablet processor rather then an ARM based one. The windows 8 tablet license isn't any more expensive then RTs either, so who would want an RT tablet over a windows 8 one?

Naturally the market will keep windows RT tablets cheaper then windows 8 ones, but from a hardware point of view that doesn't necessarily have to be the case, at least not by much.

The tablet industry is sure going to be interesting in the following 12 months.
 
I wouldn't speak too soon with confidence on this one. I am not sure if it is standards compliant usb audio. There is no mention of UAC1 or UAC2 in anything I could find on the matter, including SDK docs.

I have over the weekend just upgraded to 4.1 (JB) on my galaxy nexus but I don't have a usb adapter to test it out. I will be trying to at some point in the near future though.
 
I'm a windows guy but could never see myself choosing a RT or W8 tablet over Android. RT doesn't interest me in the least and W8 requires power hungry x86 hardware.

I've had my Android smart phone for nearly two years now and I've really grown to like the OS despite it's shortcomings.

RT doesn't interest me either, W8 on a tablet however does, which is what MS are marketing it as being able of doing. They are going to release their own tablet soon after the launch later on this year.

Current tech tablets are about as powerful as old P3/P4s at around 900MHz, coupled with 2gigs of ram and a SSD is plenty to run basic applications with a tablet orientated OS. Super long battery life isn't that important to me.
 
This is great news - they are not only working on usb audio but making it work well too. I feared it would be a first-time bodge like MS usually do. Galaxy Nexus looks like it a definite contender - 12ms latency - thank you Android developers !

Quote repeated from http://www.kvraudio.com/forum/viewtopic.php?p=4972562

"USB Audio

USB audio output support allows hardware vendors to build hardware such as audio docks that interface with Android devices. This functionality is also exposed with the Android Open Accessory Development Kit (ADK) to give all developers the chance to create their own hardware. "
 
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Good and bad news on the support of standards compliant usb audio.

Limited to 16/44.1 for now. Still great to have this officially supported now!


From: Android Open Accessory Protocol 2.0 | Android Developers
AOA 2.0 includes optional support for audio output from an Android device to an accessory. This version of the protocol supports a standard USB audio class interface that is capable of 2 channel 16-bit PCM audio with a bit rate of 44100 Khz. AOA 2.0 is currently limited to this output mode, but additional audio modes may be added in the future.

To enable the audio support, the accessory must send a new USB control request:

<see link above>

This command must be sent before sending the ACCESSORY_START command for entering accessory mode.

The implication of the bolded section may be a dealbreaker, I'm not sure though.
 
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Well I have thought about this some more.

That last line of the quote I posted above has me concerned that android will support no usb interface chip unless it is built into an android accessory that sends the correct command to android to set the android device into accessory mode.

Can anyone with an understanding of usb protocol comment on that?

EDIT: I have JB running on my galaxy nexus and going to order a micro usb otg adapter cable today so I can test it out for myself.
 
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There's something different about the way Android handles USB at the higher level. That is the 'accessory' is always treated as the master and the Android system is the slave. So its like when the two are connected the Android system needs to be driven in the appropriate way by commands from the connected device. This is quite the opposite from the way that Windows (or Linux) deals with USB. In those cases the PC is the host and the connected device just a peripheral. With Android, the tablet becomes the peripheral and the USB DAC is the host.

Don't know if this helps?
 
actually its looking like both master and slave (a modified andriod standard slave type) modes will be accepted in coming releases. the main reason for the slave mode requirement is battery power. normally the master has to either supply the power for the receiver and device, or be told otherwise by the slave. the android USB OTG standard is 100ma max, so this limits the field considerably. its still very much a work in progress, so i'm going to leave it alone for a while till they sort out a more standard protocol; even though it would suit my portable audio needs very well to have USB audio out of a tablet or phone.
 
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