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Old 1st July 2012, 10:54 PM   #31
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Quote:
Originally Posted by theAnonymous1 View Post
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.
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Old 2nd July 2012, 05:13 PM   #32
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Microsoft hardware partners aren't too thrilled with the decision by MS to bring their own tablet to the table (pun intended).

Acer CEO On The Microsoft Tablet - Business Insider
Acer slates Microsoft's hardware push | Reuters

M$ Partner thinks SLATE is DOOMED.
Why I love Microsoft?s vapourware tablet
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Old 3rd July 2012, 04:14 PM   #33
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Android, High-Performance Audio in 4.1, and What it Means – Plus libpd Goodness, Today

This article provides an overview on the Android 4.1 audio improvements.
JellyBean supports multichannel over HDMI and low-latency but no word yet on how USB audio is implemented. Apparently Windows for Mobile is looking really bad at this point.
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Old 4th July 2012, 04:17 AM   #34
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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. "

Last edited by KlipschKid; 4th July 2012 at 04:19 AM.
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Old 4th July 2012, 04:44 AM   #35
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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
Quote:
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.

Last edited by hochopeper; 4th July 2012 at 04:55 AM.
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Old 4th July 2012, 04:57 AM   #36
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So does it mean 48, 96 etc will be resampled ? Hmmm.... and what usb dac ICs will be recognised ?
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Old 4th July 2012, 06:03 AM   #37
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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.

Last edited by hochopeper; 4th July 2012 at 06:12 AM.
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Old 4th July 2012, 06:39 AM   #38
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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?
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Old 4th July 2012, 07:43 AM   #39
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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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Old 5th July 2012, 10:07 PM   #40
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