miroMEDIA Surround - Specifications
	Contents Features Technical data System requirements The working of Dolby Pro Logic Surround

• ISA board with a Dolby Pro Logic decoder to expand existing audio components
• JVC 3D-Phonic for Dolby Surround sound with only two speakers
• Five audio outputs (front left/right, center, rear left/right) to connect a complete Surround set
• Dolby Pro Logic control and adaption to the room acoustics through software
• Effect modes for stereo signals
• Compatible with DOS, Windows 3.1x, Windows 95 and Linux

• DOS, Windows 3.1x, Windows 95 or Linux
• PC (386 or faster)
• 1 free ISA slot
• Audio components (e.g. sound card, radio card or TV-tuner card, powered speakers)

In film productions the Surround sound is created by professional technicians and is packed (encoded) to the stereo tracks on recording. Dolby Pro Logic decodes and distributes it to four channels (front left, front right, center, Surround) on playback. Each channel hast its own task assigned. The center channel is important mainly for dialogs and solo voices. The Surround channel is played back through two speakers placed in the rear left and right which should point diffuse into the room.

The scetches show the positions and tasks of the speakers. Beside the often used solution with five speakers the miroMEDIA Surround is also designed for the easy to realize Phantom mode. With this mode two pairs of powered speakers can be connected directly to the Surround board and the center channel is emulated by the front speakers. With the 3D-Phonic mode the whole Surround sound is simulated with only two speakers (front left and right).

The left and right speakers create the stereo sound from the left over the middle to the right.	The center speaker mounts events and speach to the screen, the place of action.	The rear speakers let the sound move from the front to the rear and back.

Source: miroMEDIA Surround cardboard box