24/96 Squeezeplay and External USB DAC

[jemhayward]

This is really just for the nerdy HiFi fans...
The Squeezebox Touch will play high resolution audio files, and with an amazing 3rd party app from a chap called "Triode" on the squeezebox forums, it will do this via USB. I use a Touch in my main HiFi system, and the sound, via an Audiolab MDAC is absolutely stunning. Although I dont *need* to do this with my Jogglers, I seem to feel I should be able to. However, my enthusiasm isn't matched by my linux programming skills.
The otherwise perfect SqueezeplayOS is limited to 16bit/44.1kHz by the configuration file asound.conf
I also have a squeezeplay oriented installation by Gordon Cooper, which at least thinks its playing the high res files, but it wont route out via USB.

Is there anyone else out there who has the relevant skills and nerdiness to work on getting this working with me?

[Mevi]

I'm reading up on the audio capabilities of the Joggler at the moment, so your question is well timed. The STAC9202 sound chip in the Joggler is capable of 24bit and sample rates up to 192khz - up to 88khz via digital outs if you wanted to solder onto the audio chip to get optical or coax.

The question of using a USB sound card has been asked a couple of times on the forum before, so you should get an answer soon, but try a search on the forum and see if the changes you need to make are there.

[gegs]

Try the Behringer UCA202 USB soundcard. It works out of the box if you use the USB sound switch, which I think is available as an executable script in SWF Manager in PnPIII. The Behringer UCA 202 has phono, 3.5mm headphone and optical S/PDIF outputs.

I don't know anything about USB sound capabilities or modifying sound configuration files for higher bitrate audio. The quality I get at the moment is pretty good for my mediocre hi-fi setup but I'd still be interested in improving the quality of the output (who wouldn't) if anybody else knows how.

The original sound.conf specified the bitrate (48k) but the simplified version I'm using makes no mention of this. I'm not sure what bitrate the output default is in this circumstance.

[Wilberforce]

Check out:

http://forums.slimdevices.com/showthrea ... up-to-192k

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 settings = {mac="xx:xx:xx:xx:xx:xx",uuid="xxxxxxxxxxxxxxxxxxxx",alsaPlaybackDevice="plughw:0,0",alsaSampleSize=24,alsaPlaybackBufferTime=50000,alsaPlaybackPeriodCount=3,} 

in ~/.squeezeplay/userpath/settings/DesktopJive.lua

For the plughw, the first number is the card id and the second is the device. So if you

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 cat /proc/asound/cards 

to find the card id and

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cat /proc/asound/devices 

(look for playback device) for the device. Without the patch it will play stuff at its native sampling frequency up 96 khz (above that you''ll need the patch I think - my dac only goes upto to 96).

[gegs]

@Wilberforce - Thanks for the link. I'll give it a go when I have some time (probably not before the weekend).

Further down the thread wilbert-vb (not you, is it?) says this:

Thank you very much for this gem of information, I do want to add that the mentioned line results in a high CPU load. Top shows a load of 30%, fan is blowing.

When I modify the line to this, I have a normal CPU load of 1%:

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settings = {mac="xx:xx:xx:xx:xx:xx",uuid="yyy",alsaSampleSize =24,alsaPlaybackDevice="plughw:1,0",}

and fan is off.

Have you tried this method with the Joggler?

[Wilberforce]

@gegs

Cpu load is ~6% on my joggler. Unfortuantly, I think your dac is limited to 16bit, 44.4khz, but not to worry, It just means your flacs won't take up unnecessary disk space and you won't have to pay a premium for them - audiophoolery anyone?!

[gegs]

...I think your dac is limited to 16bit, 44.4khz...

I was going to upgrade the DAC on my hi-fi set-up at some point and transfer the Behringer to the kitchen Joggler. Could you recommend a better DAC? Preferably under a hundred quid.

[Wilberforce]

I was going to upgrade the DAC on my hi-fi set-up at some point and transfer the Behringer to the kitchen Joggler. Could you recommend a better DAC? Preferably under a hundred quid.

I have a dacmagic, but these http://www.richersounds.com/product/dac ... teac-udh01 look pretty good value at the moment. Look out for asynchronous usb support and a decent power supply.

[gegs]

Thanks very much for that.

I think this will have to go on my Christmas list (of presents I'll buy for myself). Despite getting loads of hints for what my wife would like "from Santa" (and heaven help me if she doesn't get at least a couple of them), whenever I mention what I would like she goes all "techno-blind" on me and I get clothes and toiletries.

[jemhayward]

So, it looks like it IS possible... I'm happy with SqueezeplayOS, so ideally I'd like a version of SqueezeplayOS (internal) that incorporates these mods. I don't think I have the skills to build one, hopefully someone here does (sounds like you do!)

[Wilberforce]

You just need to edit:

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~/.squeezeplay/userpath/settings/DesktopJive.lua 

with a text editor (nano/vi). Your dac is limited to 24/96 on the usb, so the patches aren't necessary. Do this with some sort of ssh client (putty?) - I believe you will have to install the ssh server via one of the menus in squeezeplay ('additional features' or whatever it ended up being named ;D)

added:

I imagine it will look like this for you:

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settings = {mac="xx:xx:xx:xx:xx:xx",uuid="xxxxxxxxxxxxxxxxxxxx",alsaPlaybackDevice="plughw:1,0",alsaSampleSize=24,alsaPlaybackBufferTime=50000,alsaPlaybackPeriodCount=3,} 

note the:

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alsaPlaybackDevice="plughw:1,0" 

and use the mac and uuid that are already in there.

[themystical]

I have a dacmagic, but these http://www.richersounds.com/product/dac ... teac-udh01 look pretty good value at the moment. Look out for asynchronous usb support and a decent power supply.

This looks like an interesting DAC to run with the Joggler. Having looked at its manual, it seems to suggest that you need to install drivers prior to use and only drivers for Windows/Mac are provided. Googling suggests that it has been used with Squeezebox Touch which runs Linux? provided one uses a "Triode" add on? Would this DAC be compatible with the Openpeak OS on the Joggler?

[Wilberforce]

I have a dacmagic, but these http://www.richersounds.com/product/dac ... teac-udh01 look pretty good value at the moment. Look out for asynchronous usb support and a decent power supply.

This looks like an interesting DAC to run with the Joggler. Having looked at its manual, it seems to suggest that you need to install drivers prior to use and only drivers for Windows/Mac are provided. Googling suggests that it has been used with Squeezebox Touch which runs Linux? provided one uses a "Triode" add on? Would this DAC be compatible with the Openpeak OS on the Joggler?

Yeah, like you say, the fact that it works with a squeezebox touch suggests that linux compatability is there.

[Wilberforce]

Yeah, like you say, the fact that it works with a squeezebox touch suggests that linux compatability is there.

Actually I think the original OS kernel version is too old to support class 2 usb audio devices, so whether or not it would work, I'm not too sure

[themystical]

Yes probably best to stick with class 1 usb audio devices until somebody actually tries a class 2 audio device with the Openpeak OS and confirms whether or not it is compatible. Thanks for your help Wilberforce.

[jemhayward]

I'm probably showing my ignorance here, but, I use the Triode USB on my "real" Squeezebox touch, and it works really well. Could I run the same thing on my squeezeplayOS joggler with the same result?

[Wilberforce]

I believe his plugin uses a custom kernel / jive_alsa, both of which will be compiled for a ARM target (squeezebox touch). So the answer is, "no", not with out a bit of hacking/recompilation (for x86).

[jemhayward]

ah, yes, bit beyond my competence level...

I'll play with desktopjive.lua at the weekend and will report back...

[jemhayward]

I've edited desktopjive.lua as above, but I'm still outputting 24 bit files as 16/44.1 through the USB. I think I may need to poke around inside asound.conf having read Roobarbs posts. Where will I find asound.conf?

[JimbobVFR400]

In /etc
Probably a good plan to back it up before changing.