Dead silent dedicated Linux music server for USB DAC's.

nyc_paramedic · « **on:** 5 Dec 2008, 01:54 am »

I did post about this on the Head-Fi forums a while back. I'm trying to figure out if there would be any interest in this type of setup. I would be happy to take any suggestions or answer any questions.

I decided to build a custom Linux based music server that was low-powered and completely silent. This, after being unsatisfied with most small PC's. All FLAC files are stored on my bedroom PC which is acting as NFS file server. The living room is a dedicated listening room. This server has been very stable for the last six months and sounds better than my Theta Data Basic transport; something I was not expecting.

The hardware is an off the shelf single board computer from PC Engines: http://www.pcengines.ch/
These are primarily designed as firewall/router/radio wifi solutions. Last year, the PC Engines designer started adding USB ports to several of his boards. I have experience using one of his older WRAP boards with open source Monowall (http://m0n0.ch/wall/) firewall software. I currently have months --and sometimes a year of uptime-- on this combo with nary an issue; being only powered down when I go on vacations.

I'm currently using two versions of hardware:

My original board: http://www.pcengines.ch/alix3c2.htm

The board I'm currently experimenting with: http://www.pcengines.ch/alix2d2.htm
This board has all connectors on the back which would look neater and nicer on an audio rack. There's also an extra ethernet port which could be put to use in the future.

Software stack:

Music Player Daemon (http://mpd.wikia.com/wiki/Music_Player_Daemon_Wiki). Based on the client server model. The MPD daemon runs on the ALIX, and the music is controlled by a client on another machine. Currently I either use a Nokia N800 tablet via WiFi, but I can also have a client running on the bedroom computer, or my Thinkpas laptop, all running at the simultaneously.

Operating System: Voyage Linux (http://linux.voyage.hk/) A version of Debian Linux that has been stripped down and modified to run from a compact flash card and load into RAM. No hard disk required. The major plus with Voyage Linux is that it keeps the apt packaging system; MPD being as easy to install as typing apt-get install mpd.

As a Linux user for the last ten years, it wasn't difficult to get things up and running. Took about 2 hours. Voyage Linux has scripts to copy an image to a compact flash, after which you SSH into the alix and apt-get the required packages: ALSA, MPD, NFS client. A simple editor is needed to configure a few configuration files: fstab for NFS partitions and mpd.conf. ASLA is configured with no mixers, and the configuration is for direct output via the USB sound module. MPD is also configured to buffer each song %100 to RAM before playing.

Sound: Initially feeding a Trends Audio UD-10 -> Merdian 518 (jitter reduction and 20 bit padding) -> Adcom GDA-700 HDCD DAC. Now it's feeding a Wavelength Audio Brick. Noticeably better than my Theta Data Basic transport, something I was not expecting as I was initially putting this thing together so I would not have to change CD's when I was cooking.

Benefits:

Low cost: Boards are $125 or $137 USD.
Dead silent: Fanless Geode based x86 CPU.
Reduced EMI: Industrial quality design. These two boards don't have any superfluous components such as VGA or keyboard/mouse.
Mini-PCI slots: Can be used with wireless cards. (I'm personally sticking with a wired ethernet connection)
Low power consumption: 3 watt load on my Kill-A-Watt meter when playing FLAC files.
Runs Linux: Open source design. No need to run a GUI on the server. Can be stripped down to run a minimum amount of superfluous services, unlike Windows or Mac OS X.
Multiple MPD clients available: Windows, Mac OS X, Linux, bluetooth, phones, web based, etc.

The only real negative is the configuration. Most audiophiles are either accustomed to using Windows or Mas OS X. Linux might be a real hurdle for them, especially in putting something like this together; basically a headless Linux server. But...

I'm currently researching ways to add a Web GUI front end. Something along the lines of configuring a Netgear router. Ideally, one would download a pre-configured Voyage Linux image and copy that to a blank compact flash card. Pop the CF card into the Alix board, power it up, and point your browser to a specific IP address and login. From there, one would configure MPD (location of music files, state file, database, and play list files), NFS or SAMBA, and other options.

Any interest, questions, or suggestions?

HT cOz · « **Reply #1 on:** 5 Dec 2008, 03:30 am »

It sounds like you are on to something. I own an Olive Music player and for all it is, I think a simplier approach that was rock solid and easy to use would be cool.

Theogenes · « **Reply #2 on:** 9 Dec 2008, 04:50 am »

Very interesting idea!! As I have exactly zero experience with Linux, I'm guessing you wouldn't recommend an endeavor like this for me?

brj · « **Reply #3 on:** 9 Dec 2008, 05:15 am »

I'd certainly follow such an effort, although I'm unlike to build a dedicated server for my listening room, as I'm happy enough to serve music from another room over the wireless network. My next Linux workstation will be as quiet as I can get away with simply because I don't want a wind tunnel on my desk, but it will serve as a desktop workstation in addition to RAID'ed photo/music server.

That said, I'm always curious about new and unique Linux installations, so I already appreciate the link to Voyage.

Of course, the price isn't bad, so it might still be fun to experiment...

nyc_paramedic · « **Reply #4 on:** 10 Dec 2008, 02:16 am »

Quote from: Theogenes on 9 Dec 2008, 04:50 am

Very interesting idea!! As I have exactly zero experience with Linux, I'm guessing you wouldn't recommend an endeavor like this for me?

It depends. You could attempt this several ways if you have zero experience. Maybe you have a LUG (Linux User Group) in your area, or you know of someone who has some Linux expertise who could help you out.

The installation steps (done on a Linux machine) for Voyage Linux are here: http://wiki.voyage.hk/dokuwiki/doku.php?id=installation If that looks Greek to you then I suggest you do not attempt this on your own.

I'm in the New York City area, so if there are people who would like to get together for help or group installs, that would be another idea.

Theogenes · « **Reply #5 on:** 10 Dec 2008, 03:10 am »

Thank you for the link and the advice!! I'm currently in NC, so NYC is a bit of a schlep, lol! I may see if there are any Linux-savvy guys around here I can bribe with beer... After they're done, of course :p

nyc_paramedic · « **Reply #6 on:** 10 Dec 2008, 03:18 am »

Quote from: Theogenes on 10 Dec 2008, 03:10 am

Thank you for the link and the advice!! I'm currently in NC, so NYC is a bit of a schlep, lol! I may see if there are any Linux-savvy guys around here I can bribe with beer... After they're done, of course :p

Here's a web page that keeps track of Linux User Groups: http://www.linux.org/groups/

Beer is good. And the fact that you would need help with a cool gadget like an Alix single board computer might make them a bit more interested too; geek factor and all.

P.S. Looking at your name, eisa ellinas?

UPDATE: Theres is also the ALIX 1D, which is the Mini-ITX version of their ALIX boards: http://www.pcengines.ch/alix1d.htm

Has keyboard and VGA; would probably make setting up Voyage Linux much easier.

sheppard · « **Reply #7 on:** 7 Jan 2009, 07:16 am »

nyc_paramedic,
What do you think about using a fitPC?
http://www.fit-pc.com/new/

It draws a bit more power though - 6W.

wilsynet · « **Reply #8 on:** 7 Jan 2009, 10:13 am »

It's an interesting idea. If there were an iPod Touch/iPhone remote application to control the music player daemon and it was as slick as the iTunes Remote application then I think you've got an open platform replacement for a Duet like device.

mcgsxr · « **Reply #9 on:** 7 Jan 2009, 01:31 pm »

What is the likely total cost to build something like this? I have friends from university who are LINUX geeks, so I am sure I could convince them to assist me with the s/w side of the equation.

I currently use a PC with XP Pro on it as my media server, but it is also the main PC for the family. In time, I will seek to replace it...

nyc_paramedic · « **Reply #10 on:** 7 Jan 2009, 02:05 pm »

Quote from: wilsynet on 7 Jan 2009, 10:13 am

It's an interesting idea. If there were an iPod Touch/iPhone remote application to control the music player daemon and it was as slick as the iTunes Remote application then I think you've got an open platform replacement for a Duet like device.

Theres is. It's called MPod: http://www.katoemba.net/makesnosenseatall/mpod/

There's also PMix for those of you who have Google Android phones: http://code.google.com/p/pmix/

And a video (not of me) of Pmix in action: http://smartphoneandroid.com/2008/12/08/controlling-mpd-with-android-pmix.html

nyc_paramedic · « **Reply #11 on:** 7 Jan 2009, 02:08 pm »

Quote from: mcgsxr on 7 Jan 2009, 01:31 pm

What is the likely total cost to build something like this? I have friends from university who are LINUX geeks, so I am sure I could convince them to assist me with the s/w side of the equation.

I currently use a PC with XP Pro on it as my media server, but it is also the main PC for the family. In time, I will seek to replace it...

The boards are inexpensive. I purchased mine through Netgate (no affiliation). You can check the PC Engines website for local and global distributors.

Pc Engines: http://www.pcengines.ch/order.php

I paid approximately $135 USD for my board; $12 USD for the enclosure; $12 USD for the little power supply.

nyc_paramedic · « **Reply #12 on:** 7 Jan 2009, 02:12 pm »

Quote from: sheppard on 7 Jan 2009, 07:16 am

nyc_paramedic,
What do you think about using a fitPC?
http://www.fit-pc.com/new/

It draws a bit more power though - 6W.

I am not familiar with that device. But I personally like the ALIX better as it has no superfluous devices like VGA on board. Plus, Voyage Linux has pre-compiled targets for the ALIX boards thus negating the need for you to compile a kernel or strip down the OS; much like people are doing with Ubuntu.

If someone finds it easier to have VGA for the install, PC Engined does make the ALIX 1d board in mini ITX form factor. Fanless and cheaper than a fitPC.

ALIX 1d: http://www.pcengines.ch/alix1d.htm

dwk · « **Reply #13 on:** 7 Jan 2009, 03:09 pm »

NYC - do the Alix boards have USB 2.0 ports, or are they 1.0 only? I didn't see any explicit identification of them as 2.0, which makes me suspicious.

nyc_paramedic · « **Reply #14 on:** 11 Jan 2009, 12:04 am »

Quote from: dwk on 7 Jan 2009, 03:09 pm

NYC - do the Alix boards have USB 2.0 ports, or are they 1.0 only? I didn't see any explicit identification of them as 2.0, which makes me suspicious.

They are all USB 2.0. Link to the PDF: http://www.pcengines.ch/pdf/alix2.pdf

rsreign · « **Reply #15 on:** 1 Jul 2009, 07:26 am »

What is the acceptable absolute amount to body something like this? I accept accompany from university who are LINUX geeks, so I am abiding I could argue them to abetment me with the s/w ancillary of the equation.

I currently use a PC with XP Pro on it as my media server, but it is aswell the capital PC for the family. In time, I will seek to alter it...ip pbx

lcrim · « **Reply #16 on:** 1 Jul 2009, 10:20 am »

How do you rip these flac files to your server? Is there an app that will run in Voyage that can accurately rip music from a CD?

nyc_paramedic · « **Reply #17 on:** 1 Jul 2009, 02:45 pm »

Quote from: lcrim on 1 Jul 2009, 10:20 am

How do you rip these flac files to your server? Is there an app that will run in Voyage that can accurately rip music from a CD?

I use a program called Grip; it uses cdparanoia, which also has CD offset support. I do have to re-tag all my classical FLAC's (work, composer, etc.) with a program called ExFalso. The ripping is done on the bedroom computer that is acting as the NFS server.

The ALIX server only plays music; no extraneous programs running.

If any of this doesn't make sense, or if you have any more questions then ask away.

jrebman · « **Reply #18 on:** 9 Jul 2009, 11:44 pm »

NYC paramedic,

Great idea! I administer a network in our community that uses Wall on an ALIX board and it is super reliable -- far better than even pro level Cisco stuff we had before.

Going to check out the MPD clients to see how well they work with my screen reader software (blind access software for PCs. If either the XP or web client works acceptably well, then I might just go ahead and give this a try -- for various reasons I prefer terminal access on linux anyway.

Now, if someday that spdif output could be configured to support 24/192, then it would be even better, but I'll take the USB and 16/44.1 for now as that's all either of my dacs upport.

Thanks for all the links too -- very helpful.

-- Jim

JoshK · « **Reply #19 on:** 10 Jul 2009, 03:05 pm »

Look really cool! I don't have need for this as I use a Squeezebox/Vortexbox solution currently, but its great to see good options coming to the marketplace.