xbox audio

[m4rz]

Hey,

Currently I have a distributed media network in my home to stream video to my tvs. I software modded my old xbox's (they were lying around), with linux and am running xbmc.
My question is as follows. Has anyone ever tested or know what the audio quality output of the xbox is when connecting to a stereo to play music. I currently have it hooked up to my denon (can't remember model off hand) for all my ripped movies to play dts, dd, etc. The sound quality of the movies is great, but I want to know if this could be used strictly for music. Oh yes, the majority of my music is in FLAC, so I have no issues with compression.

Thanks

 

[Johncan]

I have a software modded XBox running XBMC as well. I use it in the TV room with the stereo.

The XBox was designed to play DVD-based games and so the digital-to-analog converter (DAC) in it is designed to output at a 48 kHz sampling rate (CD's are 44.1 kHz). This means the XBox has to upsample your 44.1 kHz FLAC files to 48 kHz. Some people do not like the way that sounds and sometimes hardware upsampling can be poorly done especially with inexpensive DAC found in gaming systems. However, the guys that developed XBMC knew some people with discerning ears would be using XBMC to play audio files so they built in very nice software code to upsample from 44.1 to 48 before the hardware does it. This solution seems to be fairly well implemented and I can't hear anything that bothers me. In fact, I have been very pleased with the software modded Xbox as a media streamer.

Enjoy.

John

 

[m4rz]

Yes as have I. I have about 210 of my dvd's ripped...not fully compressed as I am more concerned with having my movies be able to play in dts or dd.

Thanks for the response. Would it be better to use an old laptop and run amorak to my vintage audio system? There would be no upsampling with the flac files.

m4rz

 

[Johncan]

If you are happy with the FLAC files with XBMC, keep using it. You will hard pressed to find software that works as nicely on an old laptop. Plus there are a few tricks you need to do with a PC to get the best sound (like bypass the Kmixer in WinXP).

John

 

[m4rz]

I am running ubuntu on my old laptop with amorak. I will check out the pc server section to see if anyone has posted any tweaks. If not, I will post what I have done...if anyone is interested.
Thanks johncan

 

[Johncan]

I am running ubuntu on my old laptop with amorak. I will check out the pc server section to see if anyone has posted any tweaks. If not, I will post what I have done...if anyone is interested.
Thanks johncan

Please do. I would love to know what you come up with.

John

 

[winters860]

I'm intrigued by this XBMC project! Can anyone elaborate on their experience running XBMC X-Boxes?

 

[m4rz]

I have 3....2 pc's serving tv shows, movies, and music....about 1 terabyte of shtuff...it works very well. I rip all my dvd's..downgrade the video a tad and ensure that the audio remains the same, saves about > 1/2 the space of a regular dvd.
I can have all 3 watching different movies from the same server without any lag, hiccups or freezing.

It all started because I hate under utilizing technology. Had one lying around, found a link for a soft mod, got all the necessary equipment et voila, distributed media system. I also built a mythtv server, and there is a myth - xbmc plugin that allows you to schedule, record, and replay television shows. The mythtv has gone by the wayside as the "free" television listing site (zaplabs) if I remember correctly, is no longer around and there is now a pay/service which I haven't signed up for ($60/year).
I have the website to do the softmod printed out along with some of my instructions, I can try and dig it up if you like?

Cheers

 

[m4rz]

So here's the skinny. The xbox as a media server (yes it can play flac), does not produce audio as well as a cdp. Actually, the sound is quite tinny with very little dynamics.
Here's where the search began. I found a very inexpensive M-Audio Audiophile usb device on local CL. Purchased it as I remember reading it was based on the 2946 which won a bunch of awards. Now, being the sorta guy I am, I get the fact that windows messes with audio when using strictly the windows audio drivers. Windows uses directsound first to send the stream to kmixer which downsamples to 16bit/44.1kHz (from kmixer there are 2 other steps where it goes to before you hear it, but I won't go into that). So, regardless of what type of sound you are expecting to hear this is what you get. The search was on...either ALSA (Linux) or ASIO (Windows)...m-audio doesn't play well with linux and I haven't been able to find support for also and the m-audio. ASIO driver allows the computer to send the data stream as it is receiving it without compromise to the audio device. Yes I could use wine, but didn't feel like spending a couple of days just making it compatable, plus this is only a test on a laptop that will be given to my daughter.

So, foobar loaded with Asio driver plugin, plugged RCA out (yes it does have spdif but who cares at this point), into sa-8500 tape m in. The sound certainly destroys how the xbox was working...but hey the xbox still works great as media server. I have only compared a couple of songs (SRV) that were ripped in FLAC to the original cd, so I can't really detail the quality as of yet. Suffice it to say that so far so good.

Again, after about a week or 2 of comparing cdp to m-audio usb with FLAC music, I will post a little more detailed finding.

 

[rdeck]

The Xbox uses the Wolfson WM9709 DAC, its a multi-bit delta-sigma and pretty good. But as mentioned earlier in the thread upsampling from 44.1 to 48khz must be done and this gives loss as the dac runs at 48khz fixed.

Here's a PDF with details on the Xbox DAC