Using Android to Drive a USB DAC

[thread]

I've been wondering this for ages.

Would it be possible for Android to drive a USB DAC? Like if I was to somehow get a micro usb to mini usb cable, would we be able to actually use the snd-usb-audio linux kernel module with the Android OS to send audio output? It seems finding such a cable might be a trick. (One might have to settle with a micro -> usb a female, usb a male -> mini deal.) ...

But just what do the hurdles look like on the Android side? I'm sort of surprised I've never heard any discussion about this.

Imagine strapping a DAC/amp like The Predator to a Droid for a truly bad ass headphone experience on the go.

 

[LouD]

I mentioned this a couple of days ago in post about cradles for Droids. I sure would like a USB DAC driver, but I suspect the market is too small, and because of limited storage capacity, you'd still be using MP3s. Either that or you have to store high-quality lossless audio on a server somwhere.

For what that fancy Dac/amp costs, you could get a Squeezebox instead. The Droid is a wonderful remote control for it, there's three or four apps. It works over wi-fi. The built in DAC is very high quality.

 

[thread]

Oh I use and love a Squeezebox3 already (with an external dac)... And I realize the market for such a feature is probably pretty small, but all the same, I would absolutely love the ability to do it. It would be like a make-shift SB.

Any devs with an actual idea what it would take in the software? I'd assume it would be pretty easy to load snd-usb-audio.ko... and the real issue would be getting Android to pipe audio through it... if that is, indeed, even a problem!

 

[thread]

... I guess that was about the interest level I expected.

 

[thread]

No interest in this at all out there?

 

[machineheadg2r]

Right now usb hosting is still in the hack phase. Gonna take some time

 

[bhjazz]

thread - yes!!!!!!! I've been thinking the same thing. Most discussions about this end with someone buying a dock that just gives them an analog, and not digital, output. No, I'm right there with you. Dig around in these forums. I posted some things a few months ago asking similar questions. I think I googled "android USB output" or "android digital USB output" or something.

In regards to using snd-usb-audio linux kernel module, I have not seen that one yet, so I'll do alittle digging. I think we're on the right track using just a different driver. I'd like to get a super simple audio app working with that driver just to verify.

Is that driver available standalone somewhere?

Personally, I don't think this would be terribly difficult, but I could be wrong. As there are simple versions of this for PC (like asio4all) hopefully we can make it work for the droid.

 

[memoryerror]

Hear hear

This is something I have been fantasizing about implementing, since I purchased my android phone. I am glad to see that others have the same idea. I think that andless might be the app to try to get it working with.

 

[DanBa]

For the time being, the standard USB devices for USB host-capable Android smartphones/tablets are only USB hubs, USB mass storage devices and USB class for human interface devices (for example, mice and keyboards).

We have to lobby for imposing USB DAC as a standard Android USB device, like a standard USB device for every Mac or PC (i.e. we don’t have to request each individual PC manufacturer to add the USB audio capability).

Google should include USB host (and USB audio) on every new Google "Nexus" device, which is supposed to be a reference Android device for others.

The 1st out-of-the-box (i.e. without modding) Android device able to support USB audio is the Android 4.0 ICS powered Archos G9.
Archos 80/101 G9

The Google issue "Enable USB audio", requesting Google to standardize USB audio on Android smartphones/tablets, is currently ranked 11 of 22,584.
Issue 24614 - android - Enable USB audio on the Galaxy Nexus (or any Android 4.0 device) - Android - An Open Handset Alliance Project - Google Project Hosting

Vote: Click on the star (it appears after signing in)

 

[DanBa]

Apparently, the USB audio feature is enabled on factory Samsung Galaxy S III:
xda-developers - View Single Post - Official Sound Quality thread

"I got my sgs3 a few hours ago and just plugged it into my Topping tp30 USB DAC/amp and it's playing audio through it to my speakers!!!"


Affordable hi-fi rig:
A sweet-sounding USB digital amplifier for headphones and speakers | The Audiophiliac - CNET News

music stored on SGS3 > SGS3 player > digital audio stream >> USB cable >> USB DAC/amp Topping TP30 >> speakers


[video=youtube;jR6Vc28NEcc]http://www.youtube.com/watch?v=jR6Vc28NEcc&feature=youtu.be[/video]

Keep lobbying for the Android USB audio standardisation (i.e. USB DAC as a standard USB device, like a USB mass storage device, for Android smartphone/tablet).
http://code.google.com/p/android/is...rs&colspec=ID Type Status Owner Summary Stars


Vote: Click on the star (it appears after signing in)

 

[DanBa]

Samsung Galaxy S III interworks with USB DAC/amp FiiO E7:
http://www.androidnz.net/2012/06/galaxy-s-...-it-really.html


music stored on SGS3 > SGS3 player > digital audio stream >> USB OTG cable >> USB DAC/amp FiiO E7 >> headphones




Samsung Galaxy S III triggers a new era of Hi-Fi for the masses with affordable rig:


. affordable (subsidized) smartphone


. affordable common USB DAC/amp compliant with PC or Mac, like FiiO E7 (us$80)
http://www.amazon.com/FiiO-Portable-Headph...39194973&sr=8-4
NwAvGuy geek’s verdict: "The biggest compliment I can pay the E7 is I can’t find much I would change for a portable product in this price category."
NwAvGuy: FiiO E7 USB DAC & Amp
"Clearly, the E7 is priced very competitively, and I consider it a good product — not some cheap Chinese stuff. Not only is the E7 packed with features, it also comes with a solid build quality, and a solid sound quality as well."
Fiio E7 Portable DAC | Headfonia


. affordable headphones, like Digitech Pro Monitor Headphones (us$50), clone of Fischer Audio FA-003, Brainwavz HM5 or Lindy Premium Hi-Fi headphones
Pro Monitor Headphones - Jaycar Electronics
"Now that I've had these for a good month I can honestly say they are my 'New' daily headphones!
I simple love the music that comes from these headphones.
They are beautifully balanced with sparkly highs that are not offensive to the ears, mid's that introduces a 'fun' factor to the music for all genres and lastly lows that are firm, bassy and goes amazingly deep with out distorting or overpowering the rest of the music.
The clarity is excellent with a very nice sound stage and for a 'closed' headphone they do sound quite open and spacious!
Isolation is fantastic especially listening to music or playing games at night.
Comfort is excellent and the 'killer' clamp grip slowly eases after regular use! I've listened to these all night and in to the early morning without wanting to take them off!"
http://www.head-fi.org/products/digitech-p...es/reviews/6900

Keep lobbying for the Android USB audio standardisation (i.e.USB DAC as a standard USB device, like a USB mass storage device, for Android smartphone/tablet).
http://code.google.com/p/android/issues/de...Summary Stars


Vote: Click on the star (it appears after signing in)

 

[DanBa]

"Android 4.1 for Developers
New Media Capabilities
USB Audio
USB audio output support allows hardware vendors to build hardware such as audio docks that interface with Android devices."
Android 4.1 for Developers | Android Developers

 

[IEATTIGER]

FiiO e7 not working

I have loaded android 4.1 on my galaxy nexus toro and have tested the fiio e7 dac connected to the nexus via a usb host cable and I can confirm after alot of testing that it does not work. It appears the new 4.1 usb audio support is through the adk and not standard alsa drivers. We will have to see if a custom rom fixes this but for now the usb audio support as we requested it is not functional.

 

[DanBa]

The USB DAC recommended by Google is a new type of device. It is not compatible with PC or Mac.
http://www.droidforums.net/forum/an...audio-any-android-4-0-device.html#post2166748

 

[DanBa]

An Android 4.1 Jelly Bean device can have:
. a standard USB audio out capability (or USB audio host capability), or/and
. an Android-specific USB audio out capability (or USB audio accessory capability).

An Android device that has the standard USB audio out capability can interwork with standard/legacy USB DAC.
A standard/legacy USB DAC can be a self-powered device, or a bus-powered device.
Some bus-powered USB DAC like the Objective DAC (ODAC) can be powered by some Android smartphone like the Samsung Galaxy S III.
If a bus-powered USB DAC requires too much power, it should connect to an Android device via a self-powered USB hub.

An Android device that has the Android-specific USB audio out capability should interwork with a USB DAC of a new type.
Such a USB DAC must provide power to an attached Android device.

The standard USB audio out mode is specified in Android specifications:
USB Host and Accessory | Android Developers
USB Host | Android Developers
UsbConstants | Android Developers
"int USB_CLASS_AUDIO: USB class for audio devices."
The Android 4.0 smartphone Samsung Galaxy S III can interwork with standard/legacy USB DAC like ODAC or FiiO E7.

The Android-specific USB audio out mode is just added in Android specifications:
UsbAccessory | Android Developers
"Android Open Accessory Protocol 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: SET_AUDIO_MODE"
Android Open Accessory Protocol 2.0 | Android Developers

Hopefully, Google and Android device manufacturers will enable the standard USB audio out mode along with the Android-specific USB audio out on their stock Android 4.1 devices. It should be available to everyone, and not only for a few ones hacking their Android device.

One of the ways to let them know that is to vote for the Google issue "Enable (standard) USB audio":
Issue 24614 - android - Enable USB audio on the Galaxy Nexus (or any Android 4.0 device) - Android - An Open Handset Alliance Project - Google Project Hosting

And please ask around.