Decoding newer format (DD+, TrueHD, AAC etc) on HTPC and then sending PCM to receiver sounding wonky

[junnywunny]

Right now I have an old receiver that doesn't support the newer formats (DD+, TrueHD, AAC, etc). What I do have however, is a HTPC that is capable of sending PCM audio through HDMI (GPU)  to the receiver. 

 

Everywhere I have read, the consensus is "it doesn't matter where the audio gets decoded, it's going to sound the same". It usually refers to a blu ray player or something that decodes DD/DTS and then sends the resulting PCM signal. They claim doing this should be similar to bitstreaming.

 

If this is so, then decoding the newer formats (ex. dolby digital plus) on my PC and then sending the PCM signal should make up for me having an older receiver, right?

 

Does PC decoding give the same result as receiver decoding? Because I have found this to not be the case for my HTPC.

 

With PCM mode, I get 5.1 audio but it sounds.. just lacking. The bass for some scenes is minimal while others it's there but just sounds off. Dialogue sounds far away and effects can be muddy. I used to think this is a normal 5.1 sounds like and was somewhat satisfied until I learned of the bitstreaming feature in fddshow. After enabling it there was a huge difference! Everything sounded right. There as a thump to combat, highs were perfect and the dialogue felt ... I can't quite describe it.I was using the same AC3 test files for these tests. I also compared other formats (e-ac3, aac, dts etc). Nothing came close to bitstreaming ac3/dts

 

Could this be a limitation due to some of my hardware? Or is it software related? 

 

I have tested MPC with ffdshow codec and LAV, also with ac3filters. They all gave somewhat similar results. Ac3 filter was kind of wacky. PotPlayer sounded the best, I'm guessing it was because of wasapi? I have also tried VLC with mixed results. MPC/VLC didn't come close to bitstreaming. Potplayer wasn't either but it was closer than the former players.

 

With DD+ taking off I was hoping to get similar results to bitstreaming without dropping $$$ on a new setup.

 

Is what I want possible?

 

Thanks for your time.

 

Specs:
Receiver: Yamaha HTR-6090

HTPC: Intel 970/12gb ram/AMD HD6870 GPU. Using realtek amd hdmi drivers for audio. Windows 7

[WereCatf]

21 minutes ago, junnywunny said:

With PCM mode, I get 5.1 audio but it sounds.. just lacking.

Your HTPC has to re-encode the audio into DTS or AC3 to get proper surround-sound, not try to output 5.1 PCM over HDMI. I have no idea if MPC or whatever can do that, but Kodi can do it.

[junnywunny]

3 hours ago, WereCatf said:

Your HTPC has to re-encode the audio into DTS or AC3 to get proper surround-sound, not try to output 5.1 PCM over HDMI. I have no idea if MPC or whatever can do that, but Kodi can do it.

Thanks for replying.

There is a codec called ffdshow I have installed in MPC which can indeed re-encode it to AC3. AC3FILTERS can do the same as well. It doesn't sound much different as to just sending PCM. Per your suggestion I have downloaded Kodi, and it sounds better compared to MPC. Similar to Potplayer. I'm assuming it's a built in codec or something. Still, nowhere closed to ac3 -> bitstream-> receiver decoding. I'm comparing similar audio that are in ac3/aac, but not sure if that's a fair comparison.