Gravis Ultrasound
The Gravis Ultrasound (GUS) soundcard family was released by Advanced Gravis during the 1990s. The original Ultrasound card was meant as a competitive product for the SoundBlaster cards as it provided sound mixing of 32 voices in hardware and came with up to 1MB of on-board sample RAM. The Ultrasound cards were quickly adopted by the demo scene as the hardware mixing ability used no additional processor power and allowed for playing back tracker modules in high quality.
The Ultrasound card family consists of the following cards:
- Ultrasound "Classic": released in 1991, 256 to 1024kB of RAM, GF1 based
- Ultrasound Max: an extended GUS Classic with an additional CS4231 codec, 1MB RAM, GF1 based
- Ultrasound ACE: addon GUS card without the codec and the SoundBlaster compatible control registers, can be used in combination with any SoundBlaster compatible card, GF1 based
- Ultrasound PnP: released in 1995, complete re-design of the GUS based on the AMD Interwave chip, 8MB RAM (16MB with h/w mod), 16bit/44kHz playback and recording possible, 1MB of sample ROM, GUS compatible when RAM is installed, PnP compatible
- Ultrasound Extreme: last GUS released by Gravis, GF1 based, ESS1688 codec for SoundBlaster comatibility, not PnP compatible, 1MB RAM
Contents
Ultrasound Classic
TBD
Ultrasound Max
TBD
Ultrasound ACE
TBD
Ultrasound PnP
Unlike any other Ultrasound card, the GUS PnP is not based on the GF1 but rather on the Interwave chip made by AMD. It is hardware compatible with the original GUS when initialized in GUS mode but differs from it in several aspects. First, it is able to play back 32 voices with the full 44kHz sample rate, where the GUS Classic went down to ~19kHz. Second, the on-board sample RAM can be extended to 8MB using SIMM, although the Interwave chip has an address space of 16MB. It also has a built-in effects processor and comes with 1MB of sample ROM filled with a GeneralMIDI compatible sound set.
As the GUS Classic, the Interwave chip is neither SoundBlaster compatible nor has it an integrated OPL3 FM chip. The card only provides the SB control registers (0x220H, 0x388H, ...), the actual SoundBlaster emulation is done in software. To be fully compatible with the original GUS, some RAM has to be installed.
DOS support
Windows support
Ultrasound Extreme
TBD
