Using Audio Advantage products for surround sound:

Many of our customers look to the Audio Advantage products to give them 
the ability to play surround sound from DVD movie discs played on their PCs. 
But how to do this, and which AA product to choose? 

USING THE OPTICAL S/PDIF DIGITAL OUT:
  All of the AA products come with a built-in Optical S/PDIF Digital Out. 
  When used with our customized driver software, all of the AA products' 
  digital outputs can act as a Dolby Digital "Pass-Thru," meaning that you 
  can use them to pass the Dolby Digital-encoded audio data from the DVD
  soundtrack to an external Dolby Digital decoder. The decoder separates the
  audio into separate channels, which are sent to the receiver's amplifiers, 
  and then to the speakers in your home theater. 

USING THE ANALOG OUTPUTS: 
  The important thing to know is that only the SRM has analog multichannel
  surround-sound outputs. The SRM's 9-pin mini-DIN jack carries the
  separate audio channels from the DVD soundtrack out to the separate
  amplifiers in your surround speaker setup. HOWEVER, you can only use this
  connection with a speaker setup that has separate analog inputs for the 
  surround channels (FRONT L/R, SURROUND L/R, CENTER and SUBWOOFER). 
  The SRM comes with an adapter cable so you can use the 9-pin DIN 
  connection with standard 1/8" stereo mini-phone plugs. 

  When using the multichannel analog outputs, the decoding must be done by a
  software DVD player installed in the computer. Programs such as WinDVD,
  PowerDVD and the version of Windows Media Player that comes with Windows XP
  Media Center Edition can decode the audio data on the DVD and send the
  separate channels to the SRM's multiple analog outputs. 
      (Windows Media Player in MCE needs to have a Dolby Digital plug-in 
       installed before it can decode the Dolby Digital surround data.)
  Also, only the SRM can be used with the new surround sound headphones, 
  such as our Ear Force HPA and X51 models. 

  The AA Amigo and AA Micro have a stereo analog output, so no more than two
  separate channels of audio can be played from their ANALOG outputs. HOWEVER,
  please don't confuse this with their Optical S/PDIF Digital Outputs! The 
  Micro and Amigo can both send Dolby Digital audio data through their S/PDIF
  Digital Outputs, to be decoded by an external Dolby Digital decoder. 


To review: 

SRM   - Has MULTI-CHANNEL 5.1 ANALOG outputs, S/PDIF Digital Output w/ Dolby
         Pass-Thru 

AMIGO - Has STEREO (2-channel) ANALOG output, S/PDIF Digital Output w/ Dolby 
        Pass-Thru MICRO - Has STEREO (2-channel) ANALOG output, S/PDIF
        Digital Output w/ Dolby Pass-Thru


Additional Features Comparison: 

Inputs:
  SRM   - Has STEREO Mic, stereo LINE IN, S/PDIF Digital Input (PCM only) 
  AMIGO - Has MONO Mic, Mono MIC/LINE IN MICRO - Has NO INPUT AT ALL 
        (for playback ONLY)

Outputs: 
  SRM   - Has stereo LINE OUT, 5.1 SURROUND LINE OUTS, S/PDIF Digital Output
  AMIGO - Has stereo LINE OUT (suitable for headphones too), S/PDIF Digital
          Output 
  MICRO - Has stereo LINE OUT (suitable for headphones too), S/PDIF Digital 
          Output

  Stereo inputs may be useful for recording from analog sources like audio
  cassette, FM radio, etc. 

  S/PDIF Digital Input is useful for making direct-digital recordings from
  digital audio sources like DAT, CD, MiniDisc, etc. 

We hope this information helps you make a more informed purchasing choice 
when looking at our Audio Advantage products. 
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