Help needed with audio setting (MP 1.3RC) (1 Viewer)

gurabli

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July 20, 2010
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I'm having this problem since previous MP versions, but now I wanted to resolve it after I have upgraded to MP1.3RC.
I have a HTPC connected to my amp via SPDIF. Amp is able to decode DTS as well. In Win7 I have SPDIF as default audio device (all the other audio devices disabled, including HDMI audio, since no need for these).

At the moment I have LAV Audio codecs everywhere (Video, TV), and Audio Renderer set as DefaultDirectSound (which should be the SPDIF out). With this setup, I can control volume, but not DTS and AC+ streams. It doesn't react on volume control, I have to use amp to adjust volume. I can however adjust mp3 or mp2 (live TV) audio (and use mute as well). It doesn't help if I choose Master or Wave as Volume Control.
If I change the Audio Renderer to MPAR (and set up LAV Audio according to WiKi), no DTS or AC+ sound is sent to my amp, just stereo.
Please help me, how should I set up audio codecs, which renderer to select and how to setup, should I use to control master or wave volume?
I just want to be able to control all sound formats with MP volume control, and to have proper Dolby Digital and DTS sound sent to my amp.
Thank you!
 

tourettes

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  • January 7, 2005
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    1) MPAR doesn't support bitstreamed audio formats (as it cannot do the required processing for such - it would require decoding which is a job for the audio decoder)

    2) You cannot control the audio volume for bitstreamed audio formats on player side, only amplifier that is decoding the encoded audio stream can do it
     

    gurabli

    Portal Pro
    July 20, 2010
    242
    5
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    Hungary Hungary
    1) MPAR doesn't support bitstreamed audio formats (as it cannot do the required processing for such - it would require decoding which is a job for the audio decoder)

    2) You cannot control the audio volume for bitstreamed audio formats on player side, only amplifier that is decoding the encoded audio stream can do it

    OK, now I think I understand it. This means that my setup was correct, it is just not possible to control volume from player side (MP in this case, or any other Windows app) if the audio is DTS and sent through SPDIF to my amp? Do I get it correctly?
     

    gurabli

    Portal Pro
    July 20, 2010
    242
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    Hungary Hungary

    No wonder that I had problems to set up volume control correctly:) It was set up correctly, i just wasn't sure that it is not possible to control every audio stream from inside of MP. I guess I will leave the volume of MP at 90%, and map the remote vol+/- buttons to the amp, and control all the volume settings using the amp and not MP.

    I'm not sure, but if I use the volume slider for SPDIF out of Windows, I'm still not able to adjust the volume of a DTS stream? Or Windows can handle this?
     

    Owlsroost

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  • October 28, 2008
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    Nothing can control the volume of a compressed bitstream (DTS/AC3/MPEG/WMA etc) without decoding it, so all Windows can do is mute it completely i.e. it's 100% or 0%. The slider is there because if the spdif stream is stereo PCM it *can* control that (like any other decoded audio).

    It's always better (from a quality perspective) to control volume with the amp - just set the windows/MP volume to 100% and forget about it.
     
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    gurabli

    Portal Pro
    July 20, 2010
    242
    5
    Home Country
    Hungary Hungary
    Nothing can control the volume of a compressed bitstream (DTS/AC3/MPEG/WMA etc) without decoding it, so all Windows can do is mute it completely i.e. it's 100% or 0%. The slider is there because if the spdif stream is stereo PCM it *can* control that (like any other decoded audio).

    It's always better (from a quality perspective) to control volume with the amp - just set the windows/MP volume to 100% and forget about it.

    Many thanks for all your help and explanation! Now I completely understand how this works. Since the whole windows/mp/codec/splitter/amp/etc involves so much variations, I was really not sure if I was doing something wrong. I recall, that I was able to use mute for DTS and AC3 stream, but not able to adjust volume. That really made me mad:)

    Remapping volume controls to amp on Harmony and putting win/MP volume to 100%.

    Once again, many thanks!
     

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