NVidia Soundstorm digital out

[fortawesome]

So after reading a bunch of pages on the soundstorm digital out (S/PDIF), I'm left feeling more confused than enlightenend...couple of questions:

1. Why is Soundstorm digital-out good? Doesn't it have to be decoded through a receiver eventually anyway (so basically it has to go through some form of DAC sooner or later)?

2. Why would the soundstorm digital-out be better than say the Chaintech's digital out? Aren't all digital signals the same?

Thanks.

 

[SilverMK3]

So after reading a bunch of pages on the soundstorm digital out (S/PDIF), I'm left feeling more confused than enlightenend...couple of questions:

1. Why is Soundstorm digital-out good? Doesn't it have to be decoded through a receiver eventually anyway (so basically it has to go through some form of DAC sooner or later)?

Usually the DACs on an external receiver are better than those on a soundcard or motherboard. On an nForce2 board, for example, the onboard Realtek solution is pathetic compared to the DACs/DSPs on many other standalone soundcards - and just about every entry-level receiver. Some cards have excellent signal processing though, like the M-Audio cards or the Creative Audigy series.

2. Why would the soundstorm digital-out be better than say the Chaintech's digital out? Aren't all digital signals the same?

Thanks.

The Chaintech AV-710 is capable of encoding and transmitting LPCM (2-channel stereo) data streams to a receiver via the optical SPDIF output. It is also capable of identifying Dolby Digital or DTS encoded data streams from pre-recorded sources like DVDs and DivX files containing AC3 tracks, then passing that information to your receiver without touching it (This is called SPDIF pass-through).

SoundStorm boards have a special hardware encoder chip called the Dolby Digital Interactive Content Encoder (DICE) or Dolby Digital Live encoder that takes any audio information from your PC and encodes it into a 640Kbps, 48KHz Dolby Digital stream that your receiver can understand.

Digital signals over SPDIF are not all created equal. Here's a quick rundown of the three basic encoding techniques that most receivers can understand:

• LPCM (Linear Pulse Code Modulation): This is the basic 2-channel stereo format used by most receivers. It is uncompressed, high-bitrate, lossless stereo information.
• Dolby Digital: This is the standard 5.1 channel audio format for DVDs. It uses a very efficient, but lossy compression algorhythm and is usually seen in bitrates between 384-448Kbps, though its capable of up to 640Kbps.
• DTS (Digital Theater Systems): This format competes with Dolby Digital by providing a higher-bitrate compression algoryhythm that is slightly less "lossy" than the Dolby format. It is usually delivered at ~1500Kbps.

Every soundcard that has a digital output can encode an LPCM stream. Only cards equipped with the Dolby Digital Live chip can encode Dolby Digital streams on-the-fly (nVidia SoundStorm, Intel HDAudio, and the HiTec HDA Digital Mystique are the only solutions to date). There aren't currently any solutions that will encode DTS streams on the fly.

 

[fortawesome]

Wow, thanks for the awesome reply. I feel less confused but now I have more questions

3. I've been blindly using the Soundstorm DAC on my DFI Infinity without realizing that :
A) the Soundstorm DAC sucks
B) the actual merits of the Soundstorm are only found in its digital output
If my goal is to gain higher fidelity in the music and movies I play through my computer, how much better would it be to use an external receiver through the digital out (compared to the onboard DAC)? What kind of differences in sound quality am I looking at here (i'm completely clueless)?

4.
So if I wanted to play around with the digital output, I imagine I will need a receiver of some sort to process the signal outside of my computer. Can anyone recommend entry / mid-entry level receivers that will allow me to hear the difference? Where can I read up on this stuff (I've looked at avsforums but that sight seemed way over my head...my eyes glazed over after a minute)?

 

[SilverMK3]

Wow, thanks for the awesome reply. I feel less confused but now I have more questions

3. I've been blindly using the Soundstorm DAC on my DFI Infinity without realizing that :
A) the Soundstorm DAC sucks
B) the actual merits of the Soundstorm are only found in its digital output
If my goal is to gain higher fidelity in the music and movies I play through my computer, how much better would it be to use an external receiver through the digital out (compared to the onboard DAC)? What kind of differences in sound quality am I looking at here (i'm completely clueless)?

No Problem, PC -> Home Theater integration is fun!
A) It does, indeed. Its too bad because nVidia came up with a great solution, but none of the motherboard manufacturers decided to implement it as well as they could have.
B) How much better than using the onboard Realtek codec? Infinately better! How much better than using a card that already has good hardware? Well... that will depend on your speakers. The advantange to using a receiver over powered multimedia speakers is not only in its signal processing capabilities, but also in its cleaner, more powerful amplifiers. You'll get a lot more out of your speakers that way! The downside is that you may need to buy new speakers because most multimedia sets don't have standard speaker-wire connections.

4. So if I wanted to play around with the digital output, I imagine I will need a receiver of some sort to process the signal outside of my computer. Can anyone recommend entry / mid-entry level receivers that will allow me to hear the difference? Where can I read up on this stuff (I've looked at avsforums but that sight seemed way over my head...my eyes glazed over after a minute)?

It really depends on your price-range. I'd stay away from Sony or JVC at any price range, instead, look for Onkyo, Yamaha, Pioneer, or Harman Kardon. You can usually find some decent "Home theater in a box" packages from these companies that include a standalone receiver and some decent speakers. Stay away from HTiB's that have a DVD player integrated into the receiver, though, as they'll usually be limited in their inputs. Check out http://www.audioholics.com for more info. Their $1000 ultimate system guide is a good place to start.

 

[GodsMadClown]

[size=+2]Dealing With Digital Output[/size]

[size=+2]What's the deal with digital audio? [/size]

Digital signals over SPDIF are not all created equal. Here's a quick rundown of the three basic encoding techniques that most receivers can understand:

• LPCM (Linear Pulse Code Modulation): This is the basic 2-channel stereo format used by most receivers. It is uncompressed, high-bitrate, lossless stereo information.
• DD (Dolby Digital): This is the standard 5.1 channel audio format for DVDs. It uses a very efficient, but lossy compression.
• DTS (Digital Theater Systems): This format competes with DD by providing a higher-bitrate compression algorithm that is slightly less "lossy" than the Dolby format.

Every soundcard that has a digital output can encode an LPCM stream. They can also usually be configured to "pass-through" streams from content with Dolby Digital or DTS audio, such as DVDs.
​

[size=+2]What is Soundstorm? or... What is Dolby Dolby Digital Live or DICE? [/size]

Some sound implementations, such as SoundStorm, have an encoder chip that runs the Digital Interactive Content Encoder (DICE) or Dolby Digital Live encoder that takes any audio information from your PC and encodes it into a Dolby Digital stream.

These implementations can encode audio output into a Dolby Digital stream in real time. Consumer hardware solutions include nVidia SoundStorm, Intel HD Audio, and the HiTec HDA Digital Mystique.​

[size=+2]Why use digital output?[/size]

Usually the DAC and output stages on an external receiver are better than those on a soundcard or motherboard. On an nForce2 board, for example, the output of the typical onboard solution is pathetic compared that on most standalone soundcards, and just about every entry-level digital receiver. With digital output, on may use the superior output of an external decoder.

However, many implementations, like those using VIA Envy or Creative Audigy audio chips, have excellent analog output. In common practice and with average budget constraints, there is little to be gained by using a digital solution, as the extra cost of the decoder will often come at the expense of the other components like speakers.​

 

[SilverMK3]

Definately!
The only thing I'd add to the last paragraph is that the encoding is done in real-time. And maybe add a link to this 3DSoundSurge technical article on SoundStorm if people want to know more about it.