Does the UD100 interwork with the (Linux) Android-powered smartphone Samsung Galaxy S III?

The Samsung Galaxy S III can interwork with the bus-powered Objective DAC (ODAC) without using a self-powered USB hub:
https://plus.google.com/1073547583314056441...sts/PCaM42irMeU
http://pastebin.com/Jjq4xnT3

Thanks!

Samsung Galaxy S III & Stoner Acoustics UD100:
http://forum.lowyat.net/index.php?showtopi...post&p=53401649

stock Galaxy S III > digital USB audio out >> USB OTG cable (micro-A to standard A cable) >> UD100 >> Sennheiser IE80

Android relies on Linux for core system services such as driver model. The Linux kernel also acts as an abstraction layer between the hardware and the rest of the software stack.
Thus Android handles all the things that Linux is really good at such as a vast array of device drivers, which take the pain out of interfacing to peripheral hardware.



Advanced Linux Sound Architecture or ALSA is a Linux kernel component.



Android includes the ALSA source code:
https://github.com/sgs3/GT-I9300_Kernel/blo...d/usb/card.c#L2


A digital audio system is composed of:



. A storage module: Music is stored in file as a series of bits 0 & 1 with different encoding formats (MP3, WAV, FLAC).
. A player: The player decodes the bits 0 & 1 to PCM digital audio signals.
. A DAC (Digital to Analog Converter): The DAC converts the PCM digital audio signals to the original analog audio signals.
. An amplifier: The amplifier amplifies the analog audio signals.
. A speaker: The speaker restitutes the music.

Like a PC or a Mac, an Android phone is a digital audio system.



The Android-powered smartphone Samsung Galaxy S III, running on a kernel with an ALSA USB audio driver, can output the PCM digital audio stream to an external standard USB DAC & amplifier, much more efficient than the internal DAC & internal amplifier.

As far as I understand, the adjustable output level feature of the ESS Sabre ES9023 chip is not implemented in the UD100 unlike in the AudioQuest DragonFly, which can be used as a USB DAC or as a USB DAC/amp (i.e. with adjustable output level control).
http://www.esstech.com/PDF/ES9023%20PB%20R...PB%20110117.pdf
http://www.head-fi.org/t/617241/audioquest...ng-tiny-dac-amp
The DragonFly allows USB Human Interface Device volume control from the player software on the USB host (i.e. PC, Mac or Android device).

However without proper USB HID digital volume control, a player software can adjust the output level "by multiplying the each successive word in the original signal data stream by a coefficient that is less than one. For example, if the incoming signal is multiplied by a coefficient of 0.5, the output will be half of the original value. This corresponds with a volume reduction of 6 dB. In a binary system, a reduction of 6 dB is the same as shifting the signal towards the least significant bit by one bit", hence a theoretical loss of resolution.

About digital volume control:
http://www.wadia.com/technology/technicalp...e_Control_2.pdf
http://www.whatsbestforum.com/showthread.p...-Volume-control

Sorry, they are not mine.
http://forums.hardwarezone.com.sg/70075257-post210.html

Yet another Stoner Acoustics UD100-based rig with FitEar TO GO! 334, the best in-ear headphone in the world according to Steve Guttenberg:
http://www.head-fi.org/t/597146/fitear-to-...75#post_8754519
http://news.cnet.com/8301-13645_3-57486297...itear-togo-334/
http://forum.lowyat.net/topic/2222840/all

stock Samsung Galaxy S3 > digital USB audio out >> USB OTG cable >> UD100 USB DAC >> Pico Slim amp >> FitEar TO GO! 334 IEM

Yes, you can.

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Added on October 24, 2012, 3:28 amThe UD100 can interwork with the stock Android powered Samsung Galaxy S III / Glalaxy Note II:
http://forum.lowyat.net/index.php?showtopi...post&p=55262420

This post has been edited by DanBa: Oct 24 2012, 03:28 AM

The Samsung Galaxy S II doesn't work with USB DAC for the time being.

The player decodes the bits 0 & 1 to PCM digital audio signals.
The Android phone, running on a kernel with a USB audio driver, can output the PCM digital audio stream to an external standard USB DAC.
http://forum.lowyat.net/index.php?act=ST&f...0#entry48908919