Subsonic Forum

I have my private CD collection (90% classical, 10% jazz) converted to flac; my hi-fi system comprises a DAC which can accept a digital stream from a pc via the usb interface. OS is Ubuntu.

Question: can I use Subsonic to stream the decoded flac files to the DAC (without going, naturally, through any intermediate conversion to any form of MP3)?

Thank you for your help.

PS: This is currently a big issue with the audiophile community of the classical persuasion, who will not be bothered to put up with monstrous Windows systems and have to engage in virus management on a daily basis. But the same community understands that in this computing age it makes much more sense to keep music as files instead of physical records. But all of this as long the system to be maintained is lean and secure and, above all, that there is absolutely no loss of audio quality.

Hi vmsda, the operating system should not play a role here, but you should have a digital audio output from your server. I am not sure how the output via USB is happening for you.

My server has a TOSLINK out which gives me an accurate, lossless PCM stream from my FLAC collection. Note that this feature was implemented by Sindre (our developer here) after the release of the current final (3.7), and hence is only usable if you recompile a current pre-release build from the sourceforge page.

Note also that the player currently stops after every track when streaming in jukebox mode in FLAC - Sindre was trying to fix this though.

Lastly, I am not sure why you would use a DAC for a purely digital signal that you are apparenly able to feed to your amplifier - why lose quality at the last step?

Hope this helped you out a bit. I am not a Ubuntu guy, but if you use the search option there are ways to select the audio output device that subsonic will use for the jukebox feature when running Linux OSes.

ff

Thank you for your prompt reply, flacflac. I hope you do not mind my pursuing the subject with some questions/comments:

"... I am not sure why you would use a DAC ... " : in my hi-fi system, all the sources (CD, Blu-ray, etc) are connected to the DAC, which performs the Digital to Analogue Conversion necessary to feed the amplifier which drives the speakers (these are part of the hi-fi system, not of the computing setup).

"My server has a TOSLINK out which gives me an accurate, lossless PCM stream from my FLAC collection": 1) Presumably, in your system, the server stores the music in FLAC format and is accessible via a web interface? 2) But which component does the decoding before the tunes get sent to the speakers? 3) May I ask which server you are using?

"... you should have a digital audio output from your server. I am not sure how the output via USB is happening for you.": I was envisaging FLAC decoding done in the pc (by Subsonic in this case), and sent to my DAC via the USB interface (hopefully by Subsonic as well). You seem to have a different picture in mind, and I certainly do not see which components your server connects to and the various functionalities involved.

If you could enlighten me further on these issues, I would be much obliged.

Hi again,

so I guess as opposed to your setup I am using a 'digital' AV receiver - while I am aware that most audiophile solutions run using a dedicated DAC and an analog amp I am just going through my Marantz 5300, which I feel for digital sources is ideal.

To answer your questions:
My server is running on Windows 7 RC, using Apache Tomcat.

Signal line:

Storage --> Subsonic via Tomcat on an Asrock Ion 330 (a great solution !) --> PCM via TOSLINK to Marantz 5300 digital input --> Elac speakers.

I was envisaging FLAC decoding done in the pc (by Subsonic in this case), and sent to my DAC via the USB interface (hopefully by Subsonic as well). You seem to have a different picture in mind, and I certainly do not see which components your server connects to and the various functionalities involved.

Sorry for confusing you, I was just not sure where the USB plug was heading. So, Subsonic will be able to generate a WAV/PCM stream from your FLAC files - and I strongly advise going that route - it reduced my CPU usage from 15-20% to 1-2% when compared to FLAC-to-MP3 transcoding.

You can select the audio device to be used for output (meaning which device inside your server will be used to transmit the PCM stream to your DAC) as outlined in this thread:

http://forum.subsonic.org/forum/viewtopic.php?t=2038

Does that help you out a bit? Maybe you can let us know what your set up looks like.

Best wishes,
ff

Hello again, flacflac:

Thank you for clearing a lot of the cobwebs I had about your previous append. I now understand that:
- what you call the server is really the box where you execute Subsonic, and it sports an S/PDIF adapter (I can use the USB instead, since my DAC supports it). Presumably, you also rip your discs there.
- your DAC is in your Marantz, whereas I have a standalone box, as is becoming increasingly usual in stereo setups like mine.

Since going back to Windows (which I left 5 years ago) is out of the question, it was nice to hear you confirm that Subsonic can decode the flac and send it over to the DAC. Unfortunately, that thread about audio device selection had me running for a pair of binoculars, but I shall try to cross that bridge when I come to it!

You ask me about my setup:
1. Stereo
Sources: Bluray Sony BDP-S350, and cable TV digital box (both connected to DAC).
Benchmark DAC1 HDR: has 1 analog, 5 digital, one USB inputs. Acts as pre-amp. One analog output to the power amplifier.
Power amplifier: Quad 306.
Speakers: 2 Quad 22L2.

2. Computer: HP Pavilion running Ubuntu, with external HDD for the flac files. The idea, as I have said, is to connect it to the Benchmark via a USB interface.

Criticisms or suggestions are obviously welcome.

Hi vmsda,

- what you call the server is really the box where you execute Subsonic, and it sports an S/PDIF adapter (I can use the USB instead, since my DAC supports it). Presumably, you also rip your discs there.

It's a server. It runs autonomously in my network and only functions as that. I do not rip discs there. It only serves, hence it's a server. Your server needs to have a digital output to get the PCM stream to your pre-amp - are you able to play music through this USB (not using Subsonic)? If not, there are solid external "sound cards" that basically act as USB-to-Coaxial or TOSLINK converters, such as this one: (apparently providing an accurate stream)

http://www.m-audio.com/products/en_us/Transit.html

It could be a solution for you if you have trouble using Ubuntu to stream to the server via USB.

Oh and maybe let Sindre know there is some more interest in having lossless jukebox streams... then we'll hopefully sooner get this little bug fixed that currrently prevents a playlist to be played in its entirety.

Best wishes,
ff

vmsda, have you ever arrived at a solution? I'm in the same boat - I have all of my music in FLAC on a PC sending SPDIF to a dedicated DAC. I'd love to be able to use my phone as a remote control for my system, but only if I'm getting bit-perfect streams to my DAC.

Hi, 90c4!

I have not found a solution and am giving up on finding one in Ubuntu. I am going to try gentoo, which is more 'transparent' than Ubuntu, and shall let you know if I am successful. Send me a private mail (pm) as a reminder since I had all but forgotten about this forum.