Skip to main content

Topic: Multichannel Sound Card (Read 7559 times) previous topic - next topic

0 Members and 1 Guest are viewing this topic.
  • j7n
  • [*][*][*][*][*]
Multichannel Sound Card
I am looking for a new sound card and considering M-Audio Revolution 7.1. Like most of currently available consumer sound controllers it has many (8) analogue outputs. Is it possible to use this soundcard as 4 (or at least 2) stereo outputs? I have nowhere to [correctly] place more than two speakers and would like separate controls for small speakers on my desk, big 100W loudspeakers and other in living room.

  • AndyH-ha
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #1
I don't know about that particular soundcard but there are plenty of genuine multi-channel soundcards with which you can output independent stereo pairs.

  • j7n
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #2
Anything specific I should look for: DSP chips, homebrew drivers (like kX)?

  • j7n
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #3
From what I read on iXBT about Rev7.1 and Rev5.1 it appears that Revolution is very inferior to older stereo sound cards (like YMF724) in terms of functionality. These cards appear to created for quality surround playback and nothing else.

What examples are there of these genuine soundcards Andy H-ha mentioned? Anyone please? I don't care about effects in games. What I want is 3-4 stereo outputs, or perhaps 3 + 1 "headphone" output.

  • Azultra
  • [*]
Multichannel Sound Card
Reply #4
Don't take those "acceleration" features into account. Today it's overwhelmingly cheaper to do mixing, EQ,  decoding/encoding, 3D sound... by a AMD or Intel's CPU
  • Last Edit: 16 December, 2006, 03:16:07 AM by Azultra

  • AndyH-ha
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #5
Staying in that same line, the Delta 44 and Delta 66 both have 2 pairs of stereo outputs. Either of the Delta 1010s have four pairs. M-audio also has some multi-channel firewire devices. Many other manufacturers produce similar products.

These are professional soundcards. They don't include game functionally for producing strange noises and effects. If you want that stuff you must do it in software. Many do have DSP mixer chips to combine multiple sources and control output levels, however.

  • j7n
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #6
Are there any technical reason why this cannot be done on 'consumer' sound cards? Isn't it all about programming a proper driver?

  • AndyH-ha
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #7
Its more about the hardware than the drivers. Professional multi-channel cards are equivalent to several lesser channel cards running in parallel. Those several converters are physically in close proximity and clocked in unison, but the channel pairs are essentially independent except for the timing.

I don't know much about the 'consumer' 5.1 and 7.1 cards. My impression is that at least some of them expect input to be a many-channeled file. The data for the different output channels are multi-plexed into one file. The card decodes that single input file into X number of outputs. The output channels can not necessarily be used independently as they can with a real multi-channel card. If you want to out only a two channel file, that is fine with the card, but you can't also send it another two channel file at the same time. The card does not have the the independent channel hardware necessary to process multiple files.
  • Last Edit: 18 December, 2006, 04:46:44 AM by AndyH-ha

  • j7n
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #8
http://www.hydrogenaudio.org/forums/index....st&p=444117

A real soundcard does A to D and/or D to A; it is an I/O device. [..] The inputs and outputs presented to an audio application are also extras, not part of a soundcard. They are functions of the driver, a bit of software.

So the software could just multiplex my audio as a surround stream and pass it to the card, if the onboard DSP could not be programmed to do that by itself. And, I can't see the reason why synchronization problems between DACs would cause any issues while the listener hears only one DAC, instead of the four simultaneously.
  • Last Edit: 04 January, 2007, 05:13:24 PM by j7n

  • AndyH-ha
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #9
I am not sure what you are trying to say. Your post seems to suggest that your statement is a conclusion you are drawing from an earlier post of mine. That post was about a topic that doesn't seem especially relevant to the basic subject of this thread.

There is software that constructs surround sound files from multiple wave files. It is also possible to mix multiple wave files in some soundcard's DSP mixers. The two are neither the same nor equivalent, however. Mixing them together, in the normal sense of the word, produces something which cannot be separated back into its component files. This is not the say a surround file works.

A proper surround sound file can be decoded back into the component parts. I doubt there is any way to timeshare one DAC between the files; one DAC is required to produce the analogue audio stream of each channel.

Finally, it occurs to me that maybe you are trying to think up a way the soundcard you referenced in the thread's first post might output two sets of independent stereo files. Encode those independent sources files into a surround sound file, sent the result to the soundcard to be soundcard to be torn apart again. Wire the card's relevant outputs to amplifiers in different rooms (or where ever). This seems like the long, hard way to go about it. I much doubt that a ready-made method exists.

  • j7n
  • [*][*][*][*][*]
Multichannel Sound Card
Reply #10
Yeah, I guess there isn't a ready solution because of no demand from users. Thank you for your time, AndyH-ha.