Audible differences between Squeezelite and MPD?

[magchiel]

New to this forum, signed up after lurking and reading hoping for some input that might help in confirming and addressing the following observation:

 

For the streaming of music from my NAS I'm a long time user of MPD pointing to a CIFS share. In pursuit of a Multi-Room audio solution, for the living room I have installed Squeezelite on my HTPC fed from LMS from the same NAS, same files as I used with MPD.

On the same playback system however, there is an audible difference between the Squeezelite and MPD chains. So much that, after having rebuilt my stack just running Squeezelite, without A-B comparison I noticed the sound being more fatiguing. After having installed MPD to A-B I was able to verify the difference quite noticeably. Compared to MPD (on my system), Squeezelite honors the 'squeeze' by sounding more compressed, less instrument separation, less transparency (apologies for any audiophile gibberish here, no other way of phrasing it).

While I'm aware of the risk of confirmation bias, a blind test with a friend (occupation: audio-engineer) has confirmed the audible difference. Not that to say that Squeezelite sounds bad, just different (and for me subjectively worse) than using MPD which basically eliminates Squeezelite for any critical listening (good enough for day-to-day casual use though).

 

Questions:

1. Is anyone able to confirm this experience? I wasn't really able to find reliable direct comparisons while researching the topic.

2. Is it just a fact that I have to accept due to the nature of the software being different, or is it worth hunting down the underlying cause because 'it shouldn't be like this'? I could imagine it's just down to different decoding libraries.

3. Given the fact that 'from ALSA down' the chains are identical, as well as up to the source material, I'm guessing it's somewhere between the files and ALSA, i.e. LMS and Squeezelite. But where should I be looking? There's no bitrate limiting or anything enabled in LMS for any of the players. File formats also untouched (i.e. set to native').

 

Full specs:

Server: Synology DS1815+, DSM 5.2, LMS 7.9.0 1433513811

Playback: Intel NUC D34010WYK + Ciúnas USB DAC, connected wifi

Amp + Speakers: Arcam AV8 + P7 to Quadral Amun VI Phonologue Gold

 

Softwarestack:

Linux distro: Ubuntu 15.10 64-bit (from mini install)

Kernel: 4.2.0-25-lowlatency

ALSA version: 1.0.25+dfsg-0ubuntu5

Squeezelite version: 1.8-1build1

Squeezelite audio config:

# ALSA output device:
SL_SOUNDCARD="hw:CARD=Amanero,DEV=0"

MPD version: 0.19.10-1build1

MPD audio config:

audio_output {
       type            "alsa"
       name            "Ciunas DAC"
       device          "hw:CARD=Amanero,DEV=0"
       auto_resample   "no"
}

Other software installed: Kodi 15.2, X11, Lirc

 

cat /proc/asound/Amanero/pcmp0/sub0/hw_params doens't produce difference while playing back on the players (i.e. sample rate matches nicely).

 

Other Squeezebox hardware in the house: Squeezebox Radio (kitchen).

 

Many thanks in advance.

[alubis]

I also feel the sound quality of MPD is much better compare to Squeezelite. I tried this on several small board computers (beaglebone black, banana pro, and cubietruck) and got the same results.

[firedog]

Are these all Redbook files?

Make sure your squeezelite setup isn't resampling the files.

[magchiel]

I also feel the sound quality of MPD is much better compare to Squeezelite. I tried this on several small board computers (beaglebone black, banana pro, and cubietruck) and got the same results.

 

Thanks. Reassuring, not that I necessarily like this conclusion however. :-\

 

 

Are these all Redbook files?

Make sure your squeezelite setup isn't resampling the files.

 

Majority is indeed Redbook FLAC (bar a few sore MP3 files here and there and some limited DSD but not indexed atm), but also hires (24/88.2, 24/96, 24/192) present and correctly playing back. As said, sample rates output by ALSA match the source material (both Redbook and hires material).

 

 

Output from systemd is straightforward and as far as I know not allowing any resampling done:

$ sudo systemctl status squeezelite
● squeezelite.service - LSB: Lightweight headless Squeezebox emulator
  Loaded: loaded (/etc/init.d/squeezelite)
  Active: active (running) since Fri 2016-01-22 09:53:33 CET; 6h ago
    Docs: man:systemd-sysv-generator(8)
 Process: 1465 ExecStart=/etc/init.d/squeezelite start (code=exited, status=0/SUCCESS)
  CGroup: /system.slice/squeezelite.service
          └─1491 /usr/bin/squeezelite -n Woonkamer -o hw:CARD=Amanero,DEV=0 -s a.b.c.d

Jan 22 09:53:33 abc systemd[1]: Starting LSB: Lightweight headless Squeezebox emulator...
Jan 22 09:53:33 abc systemd[1]: Started LSB: Lightweight headless Squeezebox emulator.

 

EDIT: currently playing back FLAC encoded SACD-rip:

 

$ cat /proc/asound/Amanero/pcm0p/sub0/hw_params
access: MMAP_INTERLEAVED
format: S32_LE
subformat: STD
channels: 2
rate: 88200 (88200/1)
period_size: 882
buffer_size: 3528

[AudioFreak]

Hi magchiel. This is interesting to hear. I agree.

 

i use a vortexbox source where MPD was the default player on version 2.1. I upgraded to version 2.3 which installs only Squeezelite as the default player. Initially I wasn't concerned as I like the Squeezelite apps better than mpad on the iPad. But like you I found it very fatiguing.

 

initially I thought it was down to the fact I'd upgraded. After all that's a kernel change etc. I posted about it on the VB forum but I think they thought I was crazy. I then installed MPD on the same system. In A-B comparisons with same hardware and same files I detected just a little extra brightness or harshness at the top end with Squeezelite which I attributed to the fatigue. Conversely, MPD was a little warmer and natural sounding.

 

i spent ages going through settings but couldn't fix it. I only use MPD now.

[Mike Rubin]

AudioFreak, I don't have major sound issues with my VB's LMS applet, but have missed having the ability to use MPD since I upgraded from 2.1 to 2.3. Exactly how did you go about retrofitting MPD to your VB? I wouldn't even know where to download the player, let alone how to install it using terminal. Any suggestions for me?

[AudioFreak]

AudioFreak, I don't have major sound issues with my VB's LMS applet, but have missed having the ability to use MPD since I upgraded from 2.1 to 2.3. Exactly how did you go about retrofitting MPD to your VB? I wouldn't even know where to download the player, let alone how to install it using terminal. Any suggestions for me?

 

Hi mike,

 

Installing Mpd is simple. You do need access to the terminal though. You can use something like putty or webssh on an iPad. Log on as root user then use this command:

yum install mpd

 

that's it

 

using it is trickier though. By default you're using Squeezelite and you need to swap that out and run mpd. I'd did this by creating two script files. A lot of commands seem to run from the /etc directory so put them there.

 

Use :

cd /etc

to move to that directory

Create a file for mpd commands:

 

vi runmpd.sh

press i and paste up to the blank line. Then save the file with ZZ (that's 2 uppercase z's)

systemctl stop squeezelite0

systemctl disable squeezelite0

systemctl start mpd

systemctl enable mpd

alsactl restore

 

Change permissions with:

chmod u+x runmpd.sh

 

repeat the above process to create a file called squeeze.sh with the commands below

 

systemctl stop mpd

systemctl disable mpd

systemctl start squeezelite0

systemctl enable squeezelite0

alsactl restore

 

Now you can run either one like so from /etc

 

./runmpd.sh

 

this will swap out the current running app, ie Squeezelite in this case, for mpd. Likewise, run ./squeeze.sh to active Squeezelite.

 

i went one step further and hacked the vortexbox gui to add menu options to run the script files. But I haven't had time to document the changes I made to accomplish that yet.

 

hope that helps anyway.....

[Mike Rubin]

Thanks so much for this, AudioFreak. Had no idea it was this complicated. I appreciate the detailed instructions but my confidence in using Linux command line is inversely proportional to the number of steps it takes to implement a change. I fear that a misstep in following your directions would result in my making my server into a brick, at least with respect to playback. I'll either soldier on with LMS or reinstall the older Vortexbox version that allows one to access both players.

[Cebolla]

Questions:

1. Is anyone able to confirm this experience? I wasn't really able to find reliable direct comparisons while researching the topic.

2. Is it just a fact that I have to accept due to the nature of the software being different, or is it worth hunting down the underlying cause because 'it shouldn't be like this'? I could imagine it's just down to different decoding libraries.

3. Given the fact that 'from ALSA down' the chains are identical, as well as up to the source material, I'm guessing it's somewhere between the files and ALSA, i.e. LMS and Squeezelite. But where should I be looking? There's no bitrate limiting or anything enabled in LMS for any of the players. File formats also untouched (i.e. set to native').

Hi magchiel

 

Could the issue be the type of network file access being employed, ie, CIFS vs HTTP file streaming? You could install, Upmpdcli, a front end client for MPD that provides an emulated UPnP renderer and see if you get a similar sonic effect streaming the same files from the Synology NAS:

http://www.lesbonscomptes.com/upmpdcli/

It might be best if you use a UPnP media server on the Synology that can be trusted not to 'accidentally' transcode the files, eg, MinimServer:

http://minimserver.com/installing.html

 

Another thing to try might be to get the Upmpdcli provided UPnP renderer emulated as a Squeezebox, by installing the squeeze2upnp/UPnP Bridge plugin for LMS. I believe squeeze2upnp uses Squeezelite to provide the Squeezebox emulation, so it would be interesting to compare the sound coming from the Upmpdcli/MPD on the HTPC + Squeezelite on the NAS combination:

http://forums.slimdevices.com/showthread.php?103728-Announce-UPnPBridge-integrate-UPnP-DLNA-players-with-LMS-%28squeeze2upnp%29

 

John

[hannibal]

Hello

I agree there is a audible difference between Squeezelite and MPD. I have the Sonicorbiter SE. I can play 24/192 files on MDP to my Schiit Bifrost non Usb Dac. The highest I can play on Squeezelite is 24/176.4 while 24/192 gets static. MPD is warmer. LMS is on the orbiter.

Nick

[Ultrarunner]

Hello

I agree there is a audible difference between Squeezelite and MPD. I have the Sonicorbiter SE. I can play 24/192 files on MDP to my Schiit Bifrost non Usb Dac. The highest I can play on Squeezelite is 24/176.4 while 24/192 gets static. MPD is warmer. LMS is on the orbiter.

Nick

 

Squeezelite plays 24/192 just fine on my microRendu and did on my Sonicorbiter as well. I didn't find MPD sounds better but it was different. But I did have some issues with MPD (maybe MPaD related), and LMS integrates Spotify, so I'm happy with Squeezelite. It sounds awesome on the microRendu!