Benefit of using HDMI vs analog on receiver connected to PC?

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Compddd

[H]ard|Gawd
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I have my Onkyo receiver connected to my PC via HDMI to an Auzentech XTHD sound card. Is there any benefit to using HDMI instead of analog cables? Any benefit to analog over HDMI?

Since I'm using HDMI I have to have a second dummy monitor because of the way HDMI works with requiring video/audio signal, this makes my GTX 480 run a lot hotter because I basically have 2 monitors in Windows 7 but only 1 in physical reality.
 
Yes. I'll give you the reasons I use HDMI (I had to buy a card to support it). They may not all apply to you but they give you an idea:

1) No ground loops. With any analog connection, there is the possibility for multiple ground points which introduce hum. I had this problem. Going digital eliminates that possibility.

2) The ability to use the receiver's processing. With my receiver, analogue multi-channel in is a direct pass through to the amp. Only thing it will do is set levels and volume. No delays, no bass redirection, no MultEQ. To get any of that, you have to have a digital connection.

3) Direct output of compressed movie soundtracks (Dolby Digital, DTS, etc). I have never been happy with how the software decodes movie soundtracks. It is always fiddling with the dynamic range, even though it shouldn't. No problem with an HDMI connection, I tell the DVD software to pass the compressed signal to the receiver. It then handles everything properly.

4) Better DACs. I don't know that I'd notice the difference, DAC differences are way overstated by audiophiles, but my receiver does have better DACs than the HTHD.
 
So if I went analog multi-channel it would use my sound card's DACs over my receiver's DACs?

How do I tell if my receiver is a direct pass through to the amp for analog?
 
for me, depending on the receiver I use.

#1) Sound Quality, the DAC on the Auzentech Prelude, is on par if not better then that on most low end receivers, and I can send 7.1 audio via analogue(I've been told on the DAC part, don't take my word for it)

#2) if your receiver does not accept multi-channel LPCM, then you are stuck with stereo, or DD/DTS encoding for anything that is not already encoded.

With my older setup(an old pioneer low end 5.1 receiver) I used analogue, when I got the AVR-789, I switched to HDMI.
 
I have the Onkyo HT-S6200 system, so the receiver is fairly high end I believe. When I'm connected to my PC the receiver says "PCM MULTI CH HDMI DSP"
 
Compddd said:
So if I went analog multi-channel it would use my sound card's DACs over my receiver's DACs?
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Yes, provided it passes the multi-channel input directly to the amp. If not then it would use your card's converters, then use an A/D on the receiver, process the audio, then a D/A again in the receiver.

How do I tell if my receiver is a direct pass through to the amp for analog?
Click to expand...

Best way is to see if the processing works on the multi-channel input. If things like MultEQ and bass redirection work, then it is not a direct pass through. It is being digitized and sent to the DSP for processing, then converted back. If those sorts of things are not active, it is probably being passed right on to the amps.
 
Now something to note is looking at that receiver, I don't see a multi-channel input. You require a 6 channel input block for 5.1, or 8 channel for 7.1. This receiver appears to have only 2-channel analogue inputs. So going analogue you would lose all surround sound.

If the second monitor output is truly problematic, your other option is to turn on the DTS Interactive encoder and use that. That will do compressed 5.1 sound via a coaxial or optical cable.
 
Compddd said:
I have the Onkyo HT-S6200 system, so the receiver is fairly high end I believe. When I'm connected to my PC the receiver says "PCM MULTI CH HDMI DSP"
Click to expand...

This means that the sound card's DSP has converted the original multichannel signal to LPCM before being sent out through the HDMI out. Thus, you're not receiving a true LPCM signal, but an upconverted one. In fact, your sound card is incapable of sending out lossless compressed multichannel audio via bitstream; the audio had to be upconverted to uncompressed LPCM before being sent out through HDMI.
 
E4g1e said:
This means that the sound card's DSP has converted the original multichannel signal to LPCM before being sent out through the HDMI out. Thus, you're not receiving a true LPCM signal, but an upconverted one. In fact, your sound card is incapable of sending out lossless compressed multichannel audio via bitstream; the audio had to be upconverted to uncompressed LPCM before being sent out through HDMI.
Click to expand...

You are very confused. For one, computers do not process audio losslessly compressed. They work on uncompressed audio. So if he is working with normal sounds form Windows or videogames, indeed the signal his receiver gets will be uncompressed. Next, LPCM doesn't mean "lossless compression" it means "linear". LPCM implies two things:

1) The stream being received is uncompressed.

2) The stream is Pulse Code Modulation (as opposed to Direct Stream Digital or the like).

A HTHD sends uncompressed audio just fine. It can also pass through compressed audio of various sorts, but only from a source like DVD or Blu-Ray. If you configure your software and hardware right it'll pass a Dolby Digital or TrueHD or whatever stream straight to the receiver.
 
Sycraft said:
You are very confused. For one, computers do not process audio losslessly compressed. They work on uncompressed audio. So if he is working with normal sounds form Windows or videogames, indeed the signal his receiver gets will be uncompressed. Next, LPCM doesn't mean "lossless compression" it means "linear". LPCM implies two things:

1) The stream being received is uncompressed.

2) The stream is Pulse Code Modulation (as opposed to Direct Stream Digital or the like).

A HTHD sends uncompressed audio just fine. It can also pass through compressed audio of various sorts, but only from a source like DVD or Blu-Ray. If you configure your software and hardware right it'll pass a Dolby Digital or TrueHD or whatever stream straight to the receiver.
Click to expand...

I assumed Blu-ray. My bad.

Actually, most multichannel games use already lossy compressed audio. In the case of the OP's sound card, it does not output a clean LPCM multichannel signal - but instead, multichannel audio had to go through the often audio-mangling DSP even with uncompressed original LPCM signals before it even reaches the HDMI out. This makes the so-called "LPCM" output already resampled by the DSP.
 
With anythng audio, I always go digital for transporting anything. Even a low quality digital cable sends data perfectly, but to send perfect analog audio...its not so cheap. Even then you have drops in gain etc etc. Digital and you can use all $3 cables and still have better quality. So HDMI.

Quality in audio the analog vs digital argument comes up lots. And the answer always goes like this. Digital can sound as "dirty" analog. Analog can never sound as "clean" as digital.
 
Again, you don't really understand what you are talking about. Signal processing does not equal compression, either bitrate or dynamic range. Soundcards do not do psychoacoustic lossy compression unless instructed to. The HTHD can, you can turn on DD or DTS encoding and output surround audio that way which is, of course, compressed but you don't have to.

So for DSP operations, of course it does, that's part of the point of owning a soundcard. Audio is heavily processed on a computer. In a game it isn't stored as a soundtrack, it is stored as multiple pieces of audio data, to be played as needed per what is happening in the game. That is processed either by the CPU, or the sound card, or both. Windows then also does processing, like volume changes, reasmpling, etc.

A good receiver will then further process the audio. Those heavy hitting Analog Devices DSPs aren't in there for show, they are to do things like bass redirection, channel delays (to sync audio) room correction and so on.

However, if you are a purist, the HTHD will allow you to disengage any processing. Switch the card to Audio Creation mode, turn on bit accurate playback, and use either ASIO or KDM/KS and you'll get bit matched playback. Most receivers can also disengage all their signal processing, if asked.

If you are thinking the "DSP' on his receiver is indicative of processing on his computer you are incorrect. HDMI does not pass data like that. It either is to let him know that the receiver itself has some processing happening, or is simply something shown for marketing.

When my HTHD is hooked to my receiver it just shows "Multi CH IN". When asked about the signal it says it is PCM With a Fs of 96kHz. Different receivers just put it in a different fashion.
 
Sycraft said:
Again, you don't really understand what you are talking about. Signal processing does not equal compression, either bitrate or dynamic range. Soundcards do not do psychoacoustic lossy compression unless instructed to. The HTHD can, you can turn on DD or DTS encoding and output surround audio that way which is, of course, compressed but you don't have to.

So for DSP operations, of course it does, that's part of the point of owning a soundcard. Audio is heavily processed on a computer. In a game it isn't stored as a soundtrack, it is stored as multiple pieces of audio data, to be played as needed per what is happening in the game. That is processed either by the CPU, or the sound card, or both. Windows then also does processing, like volume changes, reasmpling, etc.

A good receiver will then further process the audio. Those heavy hitting Analog Devices DSPs aren't in there for show, they are to do things like bass redirection, channel delays (to sync audio) room correction and so on.

However, if you are a purist, the HTHD will allow you to disengage any processing. Switch the card to Audio Creation mode, turn on bit accurate playback, and use either ASIO or KDM/KS and you'll get bit matched playback. Most receivers can also disengage all their signal processing, if asked.

If you are thinking the "DSP' on his receiver is indicative of processing on his computer you are incorrect. HDMI does not pass data like that. It either is to let him know that the receiver itself has some processing happening, or is simply something shown for marketing.

When my HTHD is hooked to my receiver it just shows "Multi CH IN". When asked about the signal it says it is PCM With a Fs of 96kHz. Different receivers just put it in a different fashion.
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This just goes to show how little I know about home theater receivers. Every single receiver that I have ever owned are stereo-only receivers with only analog inputs. And my only experience with HDMI came from connecting a Blu-ray player directly to an HDTV set, which downmixed multichannel audio to 2-channel stereo at the set. I have neither the space nor the funds to finance a full multichannel audio rig.
 
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It's complicated as hell. However, for home theatre use you needn't worry about it, just use HDMI to hook up your player and the rest is taken care of, more or less.
 
Sycraft said:
However, if you are a purist, the HTHD will allow you to disengage any processing. Switch the card to Audio Creation mode, turn on bit accurate playback, and use either ASIO or KDM/KS and you'll get bit matched playback. Most receivers can also disengage all their signal processing, if asked.
Click to expand...

Do you recommend that I do this with my HTHD? Will my games and music sound better? What is ASIO or KDM/KS and where can I turn it on?
 
Compddd said:
Do you recommend that I do this with my HTHD? Will my games and music sound better? What is ASIO or KDM/KS and where can I turn it on?
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No, not at all. The whole bit accurate thing is way overblown and is more or less audiophile crap. Your system does plenty of processing and that is the way it should be, more or less. For games you would fur sure not want to change the mode, as you want all the EAX processing available for games that use it. For music there's just no real point.

ASIO and WMD/KS are alternative methods of talking to the audio card. Normally a program will use MME or DirectSound or the like. Those undergo processing, including the Windows mixer. ASIO is a professional standard that doesn't use normal audio driver paths and so bypasses that, and KS, kernel streaming, is MS's format for direct access.

You have to have software that supports it, and it is basically only useful in recording applications.

I recommend leaving your card in gaming mode normally, entertainment mode if you are watching a blu-ray, having Windows set to 24-bit 96kHz output and things should work well.
 
The main reason for using HDMI for me is the reduction in electrical noise. I had an X-fi extrememusic with analog outputs but the noise was too annoying. I liked what the x-fi set gave me and wanted HDMI on top so the Auzentech x-fi HTHD was the natural upgrade.

In regards to music play, I use foobar2000 + WASAPI (optional component) to get an unmolested signal straight to the receiver.
 
Another issue is that many games do not support surround via digital or utilize hardware acceleration aka the soundcard. For instance, BFBC2 is DD but surround doesn't work unless you use analogue. Right?

I have been forced to use my onboard sound due to GPU coolers taking up that space. I just tried analogue and can't get my rear or side surround to work in either 4 or 5.1 or 7.1. Weird.
 
thetruth said:
Another issue is that many games do not support surround via digital or utilize hardware acceleration aka the soundcard. For instance, BFBC2 is DD but surround doesn't work unless you use analogue. Right?

I have been forced to use my onboard sound due to GPU coolers taking up that space. I just tried analogue and can't get my rear or side surround to work in either 4 or 5.1 or 7.1. Weird.
Click to expand...

No, with a HTHD everything works through HDMI. You simply order it to redirect the speaker outs to HDMI. The software doesn't know, or care, the difference. Only for media playback do you have it directly stream out the compressed audio from the DVD/Blu-ray.
 
Sycraft said:
Yes. I'll give you the reasons I use HDMI (I had to buy a card to support it). They may not all apply to you but they give you an idea:

1) No ground loops. With any analog connection, there is the possibility for multiple ground points which introduce hum. I had this problem. Going digital eliminates that possibility.
Click to expand...

I do :p

The HDMI port on PS3 kept causing ground loop noise through my speakers so I ended up using a cheater plug. There's no exposed metal on the PS3 so the good news is I'm not at risk of electricution.
 
thetruth said:
Another issue is that many games do not support surround via digital or utilize hardware acceleration aka the soundcard. For instance, BFBC2 is DD but surround doesn't work unless you use analogue. Right?

I have been forced to use my onboard sound due to GPU coolers taking up that space. I just tried analogue and can't get my rear or side surround to work in either 4 or 5.1 or 7.1. Weird.
Click to expand...

I get surround on BFBC2 and all my other games using HDMI from my Auzentech HTHD to my Onkyo receiver. It works quite nicely.
 
I found a way to automatically passthrough DD/DTS while still using LPCM Multichannel for other software decoded stuff like music and games. Install Reclock (from Slysoft forums) and enable bitstreaming support in the config. Set it to automatically load instead of other renders (or manually choose Resync rendered in MPC etc). Then for bitstreaming alone choose the HDMI output. The default device in Windows should be Speakers. Check the redirect Speakers to HDMI in the console.

This way you don't need to touch any settings for switching modes on the receiver or on the PC.
 
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