Article: Geek Speak: How To Build A BeagleBone Black MPD Music Server

[Richard Dale]

It is best to use a linear power supply with the BeagleBone, and I think the one linked to in the article is a switching one. I bought a linear PSU from Item Audio in the UK with a UK power plug. I'm not sure where you can buy a linear PSU for American voltages or with a suitable plug for Europe or America.

 

For UK readers, Farnell sell a suitable linear power supply for 10.60 UKP:

AC-DC LINEAR PSU, 5V 1A UNIVERSAL - S2226ST - STONTRONICS

 

I bought my linear power supply from Item Audio for 19 UKP:

http://www.itemaudio.com/index.php/p....html?sef=hcfp

 

It may be the same model as the Farnell one, I'm not sure.

 

Tigal sell an alternative case for 29 euros + VAT:

TIGAL - Tigal - BeagleBone Black Case (BeagleBone Black case in aluminium anodized black)

 

It makes my BeagleBone look a bit like an Apple TV, and I think it is a bit prettier than the Logic Supply one.

[Richard Dale]

Chris pardon my ignorance, so are you saying I can build this stuff and stream music from NAS? will it sound better than my multi tasked macbook. Will it play ALAC files? how about hi res Flac? for that price I would try it just out of curiosity.

 

You can play ALAC and hi res FLAC files with MPD on the BeagleBone. However, the CPU isn't very powerful compared with the Intel CPU you would find in a modern MacBook. I use AIFF files for best sound quality as they need less processing to decode them for playing. When I am playing an AIFF file and I use the Linux 'top' utility to see what percentage of the CPU that MPD is using, it is generally between about 0.7 and 2.0%, rising to 4% or so when doing NFS reads of the music tracks stored on the NAS. With ALAC or FLAC or streaming internet radio, it would be more like 6-7%. MPD doesn't read an entire track into memory before playing it, and so you need to make sure your NAS NFS setup is well tuned to avoid drop outs as the music plays.

 

I have replaced my 7 year old MacBook with Decibel and Bitperfect with a BeagleBone and I prefer the sound. I feel the treble is higher resolution, but I needed to spend quite a bit of time tuning the Linux setup to get to that state. I am not sure if it would sound better than a modern MacBook or MacMini with Audirvana and tuned for exclusive integer mode etc.

[Richard Dale]

Is there any way to make this wifi-capable without hogging up the USB port? It'd be a really nice little music server if it wasn't restricted by ethernet.

 

Also is there a way I could share [music] files with the BBB and another computer? I don't actually have a NAS so this would be extremely convenient as well.

 

If you want more USB ports to use with a WiFi dongle, then maybe the BeagleBone isn't the best solution.

 

I use a Raspberry Pi as a NAS with my BeagleBone, but I could have used another BeagleBone instead.

 

Debian Linux works fine with both the SMB and NFS file sharing protocols (and Apple AFP too). So it should be possible to set up any other computers that you have, to share their files.

[Richard Dale]

Have you tried to juggle with period_time, buffer_time and nrpacks settings?

I have seen you have set your snd-usb-audio to nrpacks=1, that is your blocks of audio data are sent every 1ms which corresponds to a high number of IRQs. Have you tried for example nrpacks=20?!

 

Thanks for the explanation of what the 'nrpacks=1' setting means. It comes from me, as I needed to add it to my Raspberry Pi ALSA settings stop ALSA logging huge numbers of warning messages. I assumed that because it was a good idea for the Raspberry Pi, it would be a good idea to use it for the BeagleBone and I suggested that K-Man tried it who it turn suggested it to Chris.

 

Is there a means of measuring the best setting? Would a setting that works best for 16/44 audio be the best setting for 24/192 audio? Or would it be best removed altogether?

[Richard Dale]

Thanks a lot for the comprehensive tutorial.

 

I'm on the same route but I'll use Cubieboard since Beagle is not available in my country and Cubie has a SATA port which is a big plus for me (too lazy to setup a NAS box). Currently collecting references all over the web while waiting my board delivery.

 

 

 

With Mopidy + Rygel, a Linux box can serve as a complete UPNP box for music . They add another layer on top of MPD as UPNP front end (Mopidy as server, Rygel as renderer). Controlled via Android Bubble UPNP, that will be a match made in heaven.

 

I think you are suggesting an interesting configuration. To me a great advantage of these cheap ARM servers is that you can play around with configurations without spending much money only a bit of time. I have tried comparing SMB with NFS on my file server and decided I preferred NFS.

 

At some point I would like to give UPNP a go and I did come across Mopidy which sounds interesting. However, if you are using it with an MPD client such as MPod or MPDroid I would assume the tablet sends commands directly to Mopidy to tell it to play a track. Whereas if you were using it with an UPNP client on the tablet or phone, the client would send commands to the UPNP server like Rygel, which in turn would stream the music to the renderer running on the BeagleBone.

 

Also I would assume that the extra gstreamer middleware layer that Mopidy uses might have an effect on the sound compared with the simpler straight to ALSA route that MPD uses. The best thing to do is to try both out and see how they sound and how convenient they are to use, and I would be interested to hear of anyone who has got a configuration working like you suggest, and how it sounds in practice.

[Richard Dale]

Not all NAS are created equal because the suggested settings as decribed in the BBB setup dit not work for me mounting the NAS share.

Mout errors (95) were the only reponse from the BBB

 

Searching internet and trying different combination this one works for me:

 

//192.168.1.xx/Data/Music /mnt/music cifs username =admin,password=wwadmin,iocharset=utf8,sec=ntlm 0 0

 

My NAS is a Netgear Readynas Duo V1 with the latest firmware from last month.

 

Playing works fine with sometimes only some small hiccups the first seconds of a new track played. Have to see how to improve this ... maybe some buffer settings ?

 

You might be able to fine tune CIFS by increasing the size of the buffers.

 

It might be worth trying NFS to remotely mount the disk rather than use SMB/CIFS. I googled for 'Netgear Readynas Duo NFS' and it does look as though is has NFS although you might need to enable it from the command line. See an earlier post from k-man for an example /etc/fstab entry on the BeagleBone, and /etc/exports line on the NAS.

 

On the other hand, Chris Connacker said that he got clicks and pops with NFS that went away when he used CIFS. In my own network I have found that NFS is more efficient.

[Richard Dale]

Let me add a bit more information, even though I don't understand all of this. My NAS is a Thecus N700. Its local IP address on my network at home is 192.168.0.50. AFP, NFS, UPnP and FTP support are disabled. Media server is disabled. Samba service is enabled. The preferred share folder is //N7700/Media. My music is stored under various subfolders, and sub-subfolders, of the Media folder.

 

So, I am wondering if by following Chris' instructions, am I pointing to a non-existent locale for my music and that's why I get the mount point cifs does not exist error message? And, if so, what do I need to try to correct this? Thanks. JCR

 

What is the exact line you have in your /etc/fstab file to mount the disk? On Linux you need to create the directory for the mount point, such as '/media/n7700' with a 'mkdir /media/n7700' command and then make sure you use the same name in the /etc/fstab line.

[Richard Dale]

I’m very excited about this project. Two questions:

Is a NAS necessary or can I just link to my music library on my Windows 7 desktop?

If I use an Airport Express to access the BeagleBone is the configuration different?

 

You can access the music library on your Windows 7 desktop as long as you export it as an SMB CIFS share. Then follow the instructions in the article for defining an entry in your /etc/fstab file on the BeagleBone.

 

I'm not sure how Airport Express fits in - as long as you are using it as a WiFi router, the BeagleBone will just be another device on your local network.

[Richard Dale]

Well, Richard (and others here), I am not quite there yet. When I opened MPaD and manually configured for my BBB, MPaD populated, sloppily, with some of the music stored on my NAS. It didn't seem to search all the way through the various subfolders and what it picked out seemed somewhat random. However, selecting an album or a track didn't get anything to play.

 

My /etc/fstab reads like this:

 

//192.168.0.50/Media /mnt/music cifs defaults,username=admin,password=admin 0 0

 

192.168.0.50 is the local address of my NAS, and Media is the main share folder.

 

Before trying further to get anything to play, I decided to try to narrow what part of the NAS that the NCMPC database would search through, so I changed the first part of the /etc/fstab line to read "//192.168.0.50/Media/Music" where "Music" is the desired music subfolder for the NCMPC to scan and serve up. Once doing that, and running an update on the NCMPC database, mPad is now devoid of any content, even though it appears to be connected per the configured players dropdown. Returning to the original /etc/fstab and running update still leaves me with a MPaD showing no artists, albums, songs or other content. So, what am I doing wrong?

 

Separately, does the USB port of the BBB power a DAC? I have mine plugged into an HRT Music Streamer II and nothing is lighting up on the DAC. Perhaps this is because no music is streaming out of the BBB, but I thought I'd see a power light on the DAC.

 

Thanks in advance for all thoughts. JCR

 

I would ssh onto the BeagleBone and see if you can see all the music tracks you expect under /mnt/music. There could be a permissions problem where some of the tracks don't have the correct permissions perhaps.

 

Look in /var/log/mpd/mpd.log and see if there are any errors about MPD trying to read the missing music tracks. You can look at the log file while the database is being built with a 'tail -f /var/log/mpd/mpd.log' command and it will show new logging info as it arrives.

 

I have had problems with the ffmpeg library not correctly reading the metadata for some of my AIFF files. I fixed that by building the latest version of the library as opposed to the standard package in Debian Wheezy, but that might be quite hard to do if you are not a programmer.

[Richard Dale]

 

Separately, does the USB port of the BBB power a DAC? I have mine plugged into an HRT Music Streamer II and nothing is lighting up on the DAC. Perhaps this is because no music is streaming out of the BBB, but I thought I'd see a power light on the DAC.

 

Thanks in advance for all thoughts. JCR

 

No, you need to use a 5 volt power supply deliverying at least 1 amp (500 mA for the BeagleBone, 500 mA for a USB peripheral) connected to the round socket, not the micro USB socket. This would explain why your HRT isn't getting powered up I think.

[Richard Dale]

24/192 STUTTERS !

Hello together - now i need help too After trying Raspyfi without luck ( USB Problems ) i bought a Beaglebone Black and did this Guide Step by Step. (At least) everything works like charm - really cool ! Only one Problem left: My async USB Dac Musical Fidelity V90 supports only 24/96 flacs via USB. I own a few 24/192 files - these should get downsampled by ALSA to 24/96 what theoretically works:

cat /proc/asound/card1/pcm0p/sub0/hw_params access:

RW_INTERLEAVED

format: S24_3LE

subformat: STD

channels: 2

rate: 96000 (96000/1)

period_size: 12000

buffer_size: 48000

BUT THE SOUND STUTTERS - CPU is 99% . Playing original 24/96 Files need 5-10% CPU.

Here is my ALSA Config in mpd.conf:

audio_output {

type "alsa"

name "USB DAC"

device "hw:1,0"

mixer_device "none"

# period_time "50000"

# auto_resample "no"

# format "44100:16:2"

}

As you can see i already tried a view things here...but without luck

Any Ideas ? Thanks and Greets from Germany/Munich

 

I use AIFF files for playing tracks with the BeagleBone Black in my main system, and playing an AIFF file consumes about 0.7% to 1.0% of the CPU, until an NFS read arrives when it rises to about 3%. When I play Apple Lossless tracks, it takes about 7% of the CPU to decode them, or 10 times more than is needed for AIFF tracks. On a modern Mac Mini the difference in processing CPU time between AIFF and Apple Lossless is very small, and probably not audible. But I think one of the trade offs you need to make when choosing between a powerful general purpose computer like a current Mac Mini, versus a small ARM based music server like a BeagleBone Black, is that you need to do as much processing as possible in advance of playing the track in real time. So the old debate about the audibility of AIFF or WAV versus lossless compressed formats like FLAC or Apple Lossless is still relevant in the world of puny ARM music servers.

[Richard Dale]

Is the beaglebone better sounding than a raspbarrey pi? or is there another reason some of you have discarded the raspbarry and prefer beaglebone?

 

The Raspberry Pi's USB implementation is buggy, and so the BeagleBone Black works with a wider range of DACs. The BeagleBone has a marginally faster processor, and the ethernet implementation doesn't go through the USB bus, like it does on the Raspberry Pi.

 

I use both a Raspberry Pi and BeagleBone in two different systems, but I haven't compared them directly as the Pi won't work with my Musical Fidelity V-Link that I use in my main system. My Raspberry Pi certainly sounds very nice driving a pair of B&W MM-1 speakers.

[Richard Dale]

iPad is on the same network. I tried beagle bone.local, port 6600, with and without password. Nothing there.

 

I encountered another problem. If the music library contains folders with diacritical characters in the title (presented as ?) these folders are skipped when browsing, so I cannot play music when there are diacritical characters. I assume that there must be a way to solve this problem. Maybe you or someone else has a suggestion?

 

Linux would expect filenames to be in UTF8 format, and so maybe the filenames of the tracks that are missing are in some other format?

[Richard Dale]

During the installation of Debian I see several times the same warning:

perl: warning: Setting locale failed.

perl: warning: Please check that your locale settings:

LANGUAGE = (unset),

LC_ALL = (unset),

LC_CTYPE = "UTF-8",

LANG = "en_US.UTF-8"

are supported and installed on your system.

perl: warning: Falling back to the standard locale ("C").

locale: Cannot set LC_CTYPE to default locale: No such file or directory

locale: Cannot set LC_ALL to default locale: No such file or directory

Could this explain why I encounter this problem with diacritical characters?

If so, where do I have to change the language settings?

 

In /etc/default/locale on my Debian based Raspberry Pi I have:

 

# File generated by update-locale

LANG=en_US.UTF-8

 

See here: https://wiki.debian.org/Locale for info about how to update your locale.

 

I think the problem with non-latin characters in filenames is more likely to be to do with how you are mounting your disk with the /etc/fstab entry. Does adding an 'iocharset=utf8' option like this make any difference?

 

 

# /etc/fstab: static file system information.

#

# Auto generated by: beaglebone-black-copy-microSD-to-eMMC.sh

#

UUID=b8d2e77b-7900-400c-b3cf-397b025f8a8b / ext4 noatime,errors=remount-ro 0 1

UUID=3C48-0567 /boot/uboot auto defaults 0 0

//192.168.1.246/Muziek /mnt/music cifs defaults,username=admin,password=admin,iocharset=utf8, 0 0

[Richard Dale]

Do you recommend against using volumio or rune? Is there any known sound quality penalty for the convenience and easier setup?

 

I tried Volumio on one of my BeagleBones and it had trouble reading the metadata from my Apple Lossless files, and was taking forever to build a database for my 2000 CDs or so of tracks. I have the same problem with the default build of MPD on Debian too.

 

I'm using Voyage MuBox instead and that reads the tracks in my library just fine. It seems to use a lot more CPU than the version of Debian that I tuned myself and use in my main system (about 30% with Apple Lossless vs 7-8%). But it is certainly sounding very good and using a higher percentage isn't necessarily a problem, although I wonder why it is occuring. I changed the default frequency scaling from 'ondemand' to 'performance'. The only problem I have it that it seems to lose the device I'm using overnight (HRT Music Streamer II+) and I have to reboot before I can start listening.

 

Voyage MuBox was very easy to install and get running. You can download it from here:

 

Supported Boards | Voyage MuBox

[Richard Dale]

Is this a known issue? It is repeatable, when I restart the bbb server, mpod will see the device, but unless I putty in, and do the following commands, no music:

 

mount -a

ncmpc

<cntrl> + U

 

another thing I noticed, when I added the text related to something along the lines of "CPU=PERFORMANCE", the file I was editing was empty, is this normal?

 

i really love the server, but would like to solve the issue of requiring a remount after every reboot. Did I miss a step?

 

final observation, when I use the "update database" button in MPoD, it doesn't do anything, refresh local cache works as expected.

 

Which version of Linux are you running on the BeagleBone? When I first tried the BeagleBone with Angstrom Linux I had this problem, along with some difficulty in getting the NTP time server working properly. I switched to Debian Linux and it all worked just fine. I believe that the latest BeagleBones come pre-installed with Debian now, rather than Angstrom.

[Richard Dale]

I can't get the BBB to boot off the MicroSD card. The card builds without error. When I apply power to the BBB while pressing the (very tiny) boot switch, no user light ever turns on. How long should that take? If I press the switch immediately after applying power, the BBB boots into Linux. The BBB shows up on my LAN scan, and I can ssh into the board. I also completed the 'apt-get update' steps, so the board seems to be ok. I've made multiple attempts, and reinitialized and rebuilt the card a second time. Mac OS X latest. Terminal session log follows. Any help appreciated.

 

sh-3.2# diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *121.3 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage 121.0 GB disk0s2

3: Apple_Boot Boot OS X 134.2 MB disk0s3

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_CoreStorage 999.3 GB disk1s2

3: Apple_Boot Recovery HD 650.0 MB disk1s3

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD *1.1 TB disk2

/dev/disk4

#: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *4.0 GB disk4

1: DOS_FAT_32 NO NAME 4.0 GB disk4s1

 

sh-3.2# dd if=/Users/gillespy/Desktop/BBB-eMMC-flasher-debian-7.4-2014-03-27-2gb.img.xz of=/dev/disk4 bs=1m

166+1 records in

166+1 records out

174068108 bytes transferred in 111.563806 secs (1560256 bytes/sec)

You need to unpack the .xz image before using dd to copy it to the SD card.

[Richard Dale]

I have completed all the setup steps, but 'mount -a' is failing.

 

Here is the verbose output.

root@arm:~# mount -a -v

mount: UUID=C924-5D92 already mounted on /boot/uboot

mount: debugfs already mounted on /sys/kernel/debug

mount.cifs kernel mount options: ip=192.168.1.20,unc=\\192.168.1.20\Music,user=thurman,pass=********

mount error(95): Operation not supported

Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

 

Looks like my share is not mounting. Here is /etc/fstab.

GNU nano 2.2.6 File: /etc/fstab

 

# /etc/fstab: static file system information.

#

# Auto generated by: beaglebone-black-eMMC-flasher.sh

#

UUID=62568e03-26ad-430c-88b9-9eabeb590e33 / ext4 noatime,errors=remount-ro 0 1

UUID=C924-5D92 /boot/uboot auto defaults 0 0

debugfs /sys/kernel/debug debugfs defaults 0 0

//192.168.1.20/Music /mnt/music cifs defaults,username=thurman,password=******* 0 0

 

Here is my setup.

Mac OS 10.9.4.

Manually configured static IP address, as above.

I am trying to have mpd index my iTunes folder. This is probably not my final configuration, but I'm trying a proof of concept.

I have set a share for the 'Music' folder in iTunes that actually contains the music files. So the share path is:

/Users/gillespy/Music/iTunes/iTunes Music/Music

'Share files and folders using SMB' is selected.' User 'thurman' is selected.

The password contains letters, numbers and the special character '$' (to avoid any unix problems).

 

Any suggestions appreciated!

 

I don't use Samba, but searching for the error you're getting I found suggestions to use 'sec=ntlm' in the mount options list after the password in your fstab entry.

[Richard Dale]

No just a normal kernel as far as I know.

[Richard Dale]

I know this is a bit late but I'd like to build a beagle bone, however I'm not sure my current configuration supports it. I don't have NAS, but I do have a 2TB external hard drive connected to a Netgear AC1900 wireless router. The router has what Netgear calls ReadyShare. Some type of build in NAS functionality. Can I use what I have and how?

 

I've just done some searching and as far as I can see 'ReadyShare' is just an easy way of setting up Windows style SMB shared drives. So you should be able to install voyage-mubox or similar on the BeagleBone Black and set it to point to the Samba share on your router.