[Q] Line out for SG2

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Hi Folks

I was looking at these docking units and I saw one of them has a line out. I was wondering if there is any adaptor to get a line out so that we can use a headphone amp and possibly get decent sound out of a sg2?

http://forum.xda-developers.com/show....php?t=1212043

Originally Posted by LondonGemini

Hi Folks

I was looking at these docking units and I saw one of them has a line out. I was wondering if there is any adaptor to get a line out so that we can use a headphone amp and possibly get decent sound out of a sg2?

http://forum.xda-developers.com/show....php?t=1212043

Hrm.. the MHL port does not carry any analog signals..

I theorize that when the phone is docked, the OS detects the dock and begins to transfer audio digitally over the HDMI/USB pins. This is then converted to an analog signal by a DAC inside the dock


EDIT: This page basically confirms my theory: http://www.datasheetdir.com/SII9290CLU+Video

There is a bridge chip in the dock that splits the USB/HDMI signal.

Originally Posted by r34p3rex

Hrm.. the MHL port does not carry any analog signals..

I theorize that when the phone is docked, the OS detects the dock and begins to transfer audio digitally over the HDMI/USB pins. This is then converted to an analog signal by a DAC inside the dock


EDIT: This page basically confirms my theory: http://www.datasheetdir.com/SII9290CLU+Video

There is a bridge chip in the dock that splits the USB/HDMI signal.

Woah, does this open doors for external DAC/Amp use? Interesting.

very very interesting there ...

The orginal Desktop Dock use data +/- as the audio line. But you need to jump pin 4 with a 365K resitor to activate this mode.


PIN:
1 : VCC
2 : D-: AUDIO LINE OUT L/R
3 : D+: AUDIO LINE OUT R/L
4 : SENSE ( CONNECT WITH SMALL 365K TO GND )
5 : GND

Check this link for more info.
modmomun.blogspot.com/2011/07/disassembly-samsung-galaxy-s2-ii.html

Originally Posted by kiattivikrai

The orginal Desktop Dock use data +/- as the audio line. But you need to jump pin 4 with a 365K resitor to activate this mode.


PIN:
1 : VCC
2 : D-: AUDIO LINE OUT L/R
3 : D+: AUDIO LINE OUT R/L
4 : SENSE ( CONNECT WITH SMALL 365K TO GND )
5 : GND

Check this link for more info.
modmomun.blogspot.com/2011/07/disassembly-samsung-galaxy-s2-ii.html

Oh wow, didn't think it was that simple

Do you know if it's a true line out? Or is it hooked up to the internal headphone amp?

Originally Posted by r34p3rex

Oh wow, didn't think it was that simple

Do you know if it's a true line out? Or is it hooked up to the internal headphone amp?

I think it the true line out. I use to connect my external amp with the desktop dock and it work like normal line. ( which is wire d- d+ to line out )

Originally Posted by kiattivikrai

I think it the true line out. I use to connect my external amp with the desktop dock and it work like normal line. ( which is wire d- d+ to line out )

I take it it's an analog line out then? Which is useless as the DAC is total crap.

Or is it digital out? Which, if you're feeding to external DAC/AMP would be far more interesting.

Originally Posted by eiraku

I take it it's an analog line out then? Which is useless as the DAC is total crap.

Or is it digital out? Which, if you're feeding to external DAC/AMP would be far more interesting.

It is the analog line out, cause it work on my cheap pc audio amp.