[ttringle]

Hi all,

Have been doing this for a long time but am not a complete technical nut about audio quality to the point that I spend thousands of dollars on speakers etc. But I am a computer networking engineer and have a pretty deep understanding of computer side of HTPC play back of HD Video and audio. I consider what I have set up to be pretty good by my ears and while I am getting older I can still generally tell the difference between good audio and lousy compressed audio.

I have had a PS3 since the original came out and I use it as my primary Bluray player. I also take the BluRays that I watch frequently and have turned some of them into MKV's.

I know this lowers the video quality and that is not in question or at all up for debate. My point for bringing it up is that when I convert these to MKV I have tried various things with the audio. But mainly I retain the DTS MA HD or the Dolby True HD etc as the original audio un-altered.

Now we come to the crux of my situation. What other than the DAC inside the PS3 would contribute to it sounding noticeably better and fuller when it is playing the same audio stream as XBMC both through HDMI into the same receiver etc.

Again I fully understand all of the moving parts when dealing with playback and configuration of these formats through a PC and have literally, many years of experience doing this. So this is not a simple configuration issue, in fact I am fairly certain its likely a basic difference it the playback of audio from XBMC as opposed to a dedicated player.

I am simply trying to understand if anything on the PC side can be changed to bring it more in line with the PS3 or understanding what the PS3 is doing that is able to bring out the sound better.

Below are the components involved.

Motherboard GIGABYTE Z77X-UP5 TH
BD Player - Original Fat PS3 using the convert to LPCM setting to get the HD audio to the receiver
Video card - Gigabyte Geforce GTX 560Ti connected to receiver via HDMI
Receiver - Onkyo HT-RC460
XBMC 12.2 Frodo

Update: I have reconfirmed what I already knew, XBMC is sending the DTS MA HD track to the receiver to be decoded, while the PS3 is sending a Multichannel LPCM stream to the receiver. I believe that i can hear more channel separation on the PS3 in addition to better bass and it is definitely louder at the same volume on the receiver. On the receiver when the mkv is playing the DTS MA HD light on the receivers display is lit, so I am fairly certain that it is not playing the core DTS track. When that happens the receiver shows straight DTS.

I also tried the latest version of Jriver and attempted to play the same clip , which is an unaltered mdv generated with makemkv from my copy of John Carpenters The Thing, and it played the same way as XBMC after directing jriver to use HDMI to the receiver.

Update 2: To remove the possibility of anything on my 560 TI being the cause I removed it and switched to the built in HDMI on my motherboard. After downloading and installing the drivers for the Intel HD 4000 which includes the HD Audio I retested the clip I have been using Chapter 7 of John Carpenters The Thing. The audio sounded exactly as it did on the Nvidia Card, even when I switched XBMC's audio settings to use only Multi channel PCM which the nvidia card does not support properly. I confirmed that with XBMC set this way it is telling the receiver its a 192khz PCM Audio stream running at 5.1 channels.
Yet the audio still sounds less rich than the PS3. I also tried the latest Oct End of month XBMC build and had the same results.

This is not earth shattering just wondering why this would be as the PS3 is now close to a decade old and hopefully someone can understand what I am hearing and whether or not there is a way to bring the PC in line with the PS3. Or whether this is a limitation of Audioengine on XBMC.

Thanks

TimT

[bimme]

Well, there are 2 possibilities here:
1.) The avr settings doesnt match, or lets say the onkyo treats both streams different.( for example the lfe channel is 10db lower when bitstreaming hd audio)
2.) The decoder inside the onkyo receiver does a Bad job and isnt as good as the decoder of the ps3 ( and the ps3 decoder isnt that great)

Anyway, louder is not better...

I sold my ps3 so i cannot test anything here, but when i compare htpc vs bluray player, there is no difference i can hear.
Another thing could be , that the ps3 does any kind of dynamic compression (dynamic volume) and the audio seems to be louder cause of that....

[ttringle]

I don't have a SW so unsure about the LFE being 10 DB lower. But I am fairly certain the receiver uses the same volume settings with regard to that for all of the hdmi inputs, but I'll check that.
I know Louder is not better, the volume that the ps3 exhibits is only part of the equation. The separation of the different channels is slightly more pronounced with the ps3 as opposed to XBMC.

I don't believe that it is the decoder in the Onkyo because I also have removed the NVidia card from the equation and was able to then set XBMC to only send multichannel PCM and that would bypass the DTS MA decoding being done by the receiver no? And even with the PC supplying PCM to the receiver it still sounded the same as when it sent DTS MA. Of course I cannot test yet because the PS3 I have is a FAT original and is unable to bit stream properly, therefore I can't tell if the decoder on the Onkyo is mangling the audio. I can say that when XBMC believes it is passing a DTS MA HD track the receiver does seem to reflect that both the on display light activates and the on screen menu confirm that it is receiving a DTS MA HD track etc.

I have those kind of settings turned off on the receiver, and I have any that can be disabled on the PS3 disabled. I prefer the original audio without modification.

[jjd-uk]

You need to compare like with like, so a blu-ray in the PS3 and a full blu-ray iso or folder rip in XBMC.

XBMC does not decode DTS-HD MA, it can only decode the 5.1 DTS core to PCM, so there should be difference to the DTS-HD MA track being bit streamed to the Onkyo for decoding, although the difference maybe subtle.