Audio quality poor on videos and XVDR.
#1
Hi, I dont think this is an OpenElec problem so posting in here.
I am running XBMC (12.0-RC3 Git:c47e925), Platform: Linux (OpenELEC - Version: 2.99.1, 3.6.11 x86_64). Built on Jan 3 2013 on a Zotac ION System.
Audio, as in mp3s for example, works very well via SPDIF or HDMI. Sound quality is perfect.

The audio quality of videos, VDR live TV or VDR recordings is very poor (XVDR). Its hard to explain what the problem is, sometimes it sounds like echo, voices are clear but background applause is terrible and fades in and out. I have checked the VDR recordings using ProjectX and they are error free. I tried all the options on the "sync audio to video setting". If I select the .mp2 audio track on a VDR recording then the sound is much better than with the .ac3 track but still far worse than an .mp3.

As I said I believe that the audio output device settings etc. are OK as mp3s are very good.

I am connecting to a Denon Amp via SPDIF and a converter to cinch (no support of DTS etc. so only PCM output is supported via SPDIF), but outputing audio over HDMI to my Samsung TV gives me exactly the same audio problems.

I assume its some setting that is incorrect as I am pretty new to XBMC, but can't seem to find the correct one.
BTW. The sound is really really bad, I'm not being a Hi-Fi but here.
Thanks in advance.
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#2
Ha, I got it to work OK, at last.
On the audio menu for Videos there are two sliders at the top, I needed to reduce the "Volume Amplification" down to 13db.
Now the quality is brilliant (as it should be I would say).
I assume it was some kind of clipping or automatic gain control thing going on.

Cheers
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#3
Be careful - setting Volume Amplification to 13db is quadrupling the signal! Each 6db gain approximately doubles the output level - which introduces compression of the audio. Ideally this value is set to 0db and only increased for very quiet audio tracks.
System: XBMC HTPC with HDMI WASAPI & AudioEngine - Denon  AVR-3808CI  - Denon DVD-5900 Universal Player  - Denon DCM-27 CD-Changer
- Sony BDP-S580 Blu-Ray  - X-Box 360  - Android tablet wireless remote - 7.1 Streem/Axiom/Velodyne Surround System
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#4
Wink 
(2013-02-02, 02:29)DDDamian Wrote: Be careful - setting Volume Amplification to 13db is quadrupling the signal! Each 6db gain approximately doubles the output level - which introduces compression of the audio. Ideally this value is set to 0db and only increased for very quiet audio tracks.
Nope, you seem to have this wrong. The scale seems to go from 0db to 60db, with 60db being the loudest. So me setting
13db is far less dangerous than the 60db that was set directly after the install. What you say is generally correct (IMHO)
it just doesn't seem to fit to this scale, why would they allow an amplification of 60db? OTOH maybe then all my videos
and live TV via XVDR have very quiet audio tracks, but I never noticed that before.
Strange.

Thanks anyway.

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Audio quality poor on videos and XVDR.0