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hello all,
i'm audiophile and i'm working to put in place an audio player with a little CUBOX.
I made some tests and i really satisfied by XBMC with Geebox distribution but i have an issue with the new audio engine with Frodo version released.
It seems that the audio streams output are not bit perfect.
I'm using an USB DAC connected to my cubox. ( USB link)
The audio output device is selected to XMOS SPDIF ( USB DAC driver)
The configuration of audio speakers is SPDIF/COAX with 2.0.
The audio is playing but without bitperfect ( i can test it with my DAC and a specific wav file in XBMC)
With last version of XBMC ( 11) it is working well at bit perfect.
The audio output device was selected to XMOS SPDIF ( USB DAC driver)
The configuration of audio speakers was ANALOG with 2.0.
and with this configuration the audio USB link is bit perfect...
now with frodo version bit perfect disapeared. I can't select ANALOG in speaker configuration... !!!! i have just COAX/SPDIF it seems the good one but not working as expected ...
how can I parameter new audio engine of frodo version to be bit perfect with USB DAC ? maybe i have to change some XML file to parameter more depper...
Can some one help me please.
Thanks in Advance
Alex
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2013-04-26, 20:35
(This post was last modified: 2013-04-26, 21:04 by robo989.)
I decided to move away from it and just encode my stuff back to DTS-HD from FLAC in the end.
AE still has a way to go imo and isn't audiophile enough when considering the context of the audio I use it for - lossless. There's certainly mixing taking place no matter what settings you chose.
Before going back to DTS-HD, I tested things extensively and messed arounf with all the advanced settings xml stuff I could and still found a noticeable difference in quality between lossless FLAC outout and DTS-HD lossless decoded at receiver end quality. To make sure it isn't the receiver that has different pathways for DTSHD I did some tasting with LPCM direct from a bluray encode and the FLAC still sounded worse with less dynamic range, detail and more harsh.
Not sure if coincidence but I also noticed that AE audio quality was better from my perceptions when it was first in testing before being merged to master about 9-10 months ago. Since frodo12 I've felt the sound isn't as good as then, this is completely subjective though and haven't done any like for like testing but it would certainly match with what you are saying.
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DTS-HD over SPDIF is not possible, unless you have a 2.0 track. Xbmc currently assumes DTS-HD is 8 channel surround, but spdif only allows 2 (real) channels.
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Thanks to you anwsers,
In fact the connection is made by an USB cable between my cubox and my DAC.
so XBMC has to manage an USB sound card with USB cable.
The USB driver detected by XBMC in the audio panel is "XMOS SPDIF sound driver"
Now the configuration i choose in the Speaker configuration is SPDIF ( Frodo 12.0) but in the last version ( Eden 11.0) i really choose ANALOG in the speaker panel and i had sound bit perfect with my USB cable...
it is ok i have sound with Frodo version but the issue is that digital audio coming from the XMOS driver with XBMC is now NO bit perfect...i'm sure that the issue is coming from new XBMC ( 12.0) now i want to discover how i can configure new audio engine to have bit stream without any manipulation ( digital conversion, fading, digital volume, mixing etc...) i want to have the pure bitstream coming from my PCM files...
I want to have just music 2.0 at maximum quality with my external DAC.
So i'm sure I have to configure some XML files inside XBMC configuration to keep bit perfect..
Who can help me to configure the new audio engine to have that. For me I need just audio in 2.0 with USB DAC connection
Thanks in advance
T
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nickr
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My guess:
Set audio to optical/coax
Speaker config 2.0
Disable Boost Volume on Downmix
Disable everything else
Set passthrough device to the appropriate device.
If I have helped you or increased your knowledge, click the 'thumbs up' button to give thanks :) (People with less than 20 posts won't see the "thumbs up" button.)
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Thank you for the anwser.
I already made that but unfortunately. it is not working well...
Maybe Ihave to set some configuration in advancedsettings.xml or something like that ?
I'm trying to set audiophile settings to 1 but it seems not working ..
who can help me ?
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OP,
what exactly are you looking for, can you rephrase the question..
when your sound device is set to pass-thru, how do you know that sound is not bit-perfect ??
does your dac report the frequency used ?? if your dac has frequency display, play different frequency music files and see if correct frequency is played, if it reports the same then it is bit-perfect..
BTW, which OS are you using ?? all depends on this. if using windows then you need to bypass the windows mixer totally....
personally i use the Linux flavor of Openelec frodo, the sound is bit-perfect...
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2015-01-05, 22:17
(This post was last modified: 2015-01-05, 22:19 by bh69.)
fritsch - problem I have described has nothing to do with flac decoding ! I play wav files. There is something wrong with the way how original data (no matter if played from wav file or decoded from flac or ape) are processed and sent via USB to DAC. They are changed someway.
And as I mentioned before, the same test passed with older OpenElec/xbmc ...
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2015-01-05, 22:39
(This post was last modified: 2015-01-05, 22:39 by bh69.)
Personally I don't like your way of testing. It's intransparent. The old test results were plain wrong :-) and now?
I don't understand what you mean at all ..
I made only an "official" test of Audiolab M-DAC - why it should be "intransparent" ?
And what do you mean that old test results were wrong ?
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fritsch
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I don't know what that software tests. Sending a 16 bit signal via a 32 bit sink format is absolutely lossless - does not harm, does nothing, when the sink now tells: "I wanted a 16 bit signal" - then it is 100% wrong ... do you understand that?
We don't even know what this thingy is testing.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.