Help can you output audio from the USB?

[tikigod19]

Hi all,

very simple question that I cant seem to get answered on google. I am thinking of getting a USB car kit for my new car and wanted to be able to plug my S2 in (via micro USB to USB converter cable) but I can't find out for sure that the phone will actually output audio through the USB. I assume it will as that's the only output it has other than the 3.5mm.

Confirmation on this would be much appreciated.

 

[GalaxyS2]

Not 100% sure but did read something in the settings for it to use external speakers when docked. So I'm guessing so.

 

[Teknik]

The official galaxy car dock has the ability to do this through the micro usb, not sure if anything else can though.

 

[lotus49]

I have also seen speaker docks for sale specifically designed for the SGS2 so it must be possible.

 

[tikigod19]

but it sounds like it might ONLY be doable with an official samsung product?

Although surely USB is USB...?

 

[TobesEtc]

There are two ways of getting "audio" out of the SGS2 micro-USB socket in a car.

1) Official Samsung Vehicle Dock connects via the micro-USB and then has two outputs from that - a 3.5mm audio that can go to a car aux-in and another micro-USB for charging.

2) If you connect micro-USB to USB your car head unit should be able to read the music files off your SGS2 as if it were a mounted drive.

As yet there is no way to push digital audio out of the micro-USB like you can with certain...ahem..."other" devices "proprietary connectors". I have searched & searched, experimented, begged... fyi I use method 1. It is excellent - and the car mode works a treat.

 

[tikigod19]

2) If you connect micro-USB to USB your car head unit should be able to read the music files off your SGS2 as if it were a mounted drive.

This is one thing the guy from the car kit manufacturers asked me when I was quizzing him and I said I couldn't be sure so that helps.

As yet there is no way to push digital audio out of the micro-USB

This is strange as people have said they have seen docks. Unless the docks use the usb for charging only and then the 3.5 for audio.

The only issue with using that 2 cabled technique is that I didnt think you got more than 5amps of power through the USB sockets on things like this meaning it would hardly charge it at all...?

I dont have a 3.5mm in on my stereo either, if I did I'd just get a cigarette lighter micro USB charger wired to my fuse board (to leave the cigarette lighter socket free) and terminate a 3.5mm cable at the same point (where the phone will mount) and have that connected to the head unit

 

[lotus49]

The only issue with using that 2 cabled technique is that I didnt think you got more than 5amps of power through the USB sockets on things like this meaning it would hardly charge it at all...?

5 Amps! That's going to completely melt your phone and possibly bits of your car too. I suspect you may have got your units mixed up here.

 

[tikigod19]

i never knew much about electronics... perhaps it was milliamps?

edit: 5 volts sounds more realistic doesnt it? i.e - less than half than I'd get from the cigarette lighter?

 

[TobesEtc]

Can I just add that I would love a firm such as Dension to come up with some way of outputting digital audio from the micro-USB socket of an Android phone.

I spent an arm & a leg on a Dension Gateway 500 to connect the stereo in my car to my old iPod. I'd have loved a straight swap of cable (maybe with an app). But as I do have phono-in sockets on the Gateway, I just used a 3.5mm to phono cable and, as they say, "Bob is your mothers brother!" ;o)

 

[tikigod19]

what does "use external speakers when device is docked" mean in the settings? Is this nothing to do with audio through USB then?

 

[OldBeno]

There are two ways of getting "audio" out of the SGS2 micro-USB socket in a car.

1) Official Samsung Vehicle Dock connects via the micro-USB and then has two outputs from that - a 3.5mm audio that can go to a car aux-in and another micro-USB for charging.

2) If you connect micro-USB to USB your car head unit should be able to read the music files off your SGS2 as if it were a mounted drive.

As yet there is no way to push digital audio out of the micro-USB like you can with certain...ahem..."other" devices "proprietary connectors". I have searched & searched, experimented, begged... fyi I use method 1. It is excellent - and the car mode works a treat.

Yup these are the only ways I can get it to work with my denon 404u head unit as well...and like you sir i have gone with method 1 as navigating my phone as a usb device through the head unit is OK for about 2 tracks but sucks when you want to navigate an actual music library...

what does "use external speakers when device is docked" mean in the settings? Is this nothing to do with audio through USB then?

When in the dock and ticked this outputs sound through the phono socket in the dock so sound comes out the stereo....if it's not ticked then sound comes out of the phone speakers..

 

[mfj197]

There are two ways of getting "audio" out of the SGS2 micro-USB socket in a car.

1) Official Samsung Vehicle Dock connects via the micro-USB and then has two outputs from that - a 3.5mm audio that can go to a car aux-in and another micro-USB for charging.
-SNIP-

The one big problem with this route is that I believe you can't have your phone in a protective case as then it won't fit in the car dock? Having badly battered my old iPhone 3G over many years I don't want to take the chance with the SGS II so have a (slim) case. Are there any cables providing the car dock functionality? There's a worst-case solution of having a micro-USB extender cable plugged into the dock at one end and into the phone in another cradle, but that would be hopeless!

 

[brentus]

G'day All. First post.
Was giving this question some thought as I was looking for the same answer but I'm going to try something in the next few days.
I'm going to hook up a USB sound card to the phone. Will probably have to try it through a powered usb hub (power to the phone (I hope depending if voltage can travel back)) and power to the sound card) but at least it will give us a possible solution.
Has anyone tried this already?

 

[Gembeck]

The Samsung Car dock plugs into the mini usb port on the phone.
The dock then provides a mini usb port for charging, and a 3.5mm audio plug for sound.
Logic tells me (unless I'm really missing something here) that the phone usb port must be sending sound.
Maybe it uses a different pin configuration than other phones.

 

[mfj197]

The Samsung Car dock plugs into the mini usb port on the phone.
The dock then provides a mini usb port for charging, and a 3.5mm audio plug for sound.
Logic tells me (unless I'm really missing something here) that the phone usb port must be sending sound.
Maybe it uses a different pin configuration than other phones.

I think your logic is perfectly sound! The phone USB port must be sending sound somehow but how to access that apart from using the Samsung Car dock?

 

[3waygeek]

The car dock probably does this by placing a specific resistance value across micro-usb pins 4 & 5. When the phone senses that resistance value, it knows it's connected to a car dock and thus spits out audio data that the dock can understand. IIRC, from my reading over at XDA, the magic resistance value for the car dock is 619K ohms.

 

[mfj197]

The car dock probably does this by placing a specific resistance value across micro-usb pins 4 & 5. When the phone senses that resistance value, it knows it's connected to a car dock and thus spits out audio data that the dock can understand. IIRC, from my reading over at XDA, the magic resistance value for the car dock is 619K ohms.

That's good information, thanks. Any links you could share with us for further reading? I'd happily modify a cable to do this!

 

[3waygeek]

This XDA thread seems to be the source for all the various things I've read about resistance values on the SGS2.

 

[mrushabh]

I will be constructing and selling around 10 of these cables (Micro USB to audio out+charging). Please email me on m.rushabh@gmail.com if interested.