Ensoniq AudioPCI

Their cards were very popular with PC OEMs, but their costs were too high and their musical instrument division was fading in revenue.

Pressure from intense competition, especially with the dominant Creative Labs, was forcing audio card makers to try to keep their prices low.

The board consists only of a very small software-driven audio chip (one of the following: S5016, ES1370, ES 1371) and a companion digital-to-analog converter (DAC).

The DOS and Windows drivers support sample-based synthesis through Ensoniq's ".ecw" patch set format.

It is also disappointing considering the incredible popularity and longevity of the Ensoniq ES1370 chipset and its descendants, some of which were still in use six years after the original AudioPCI board, and the fact that DOS drivers for the far newer Sound Blaster Audigy still use ".ecw" wave sets.

Creative was struggling with the challenge of legacy support as well, and had created the SB-Link, an interconnect that allowed access to the serial-IRQ and PC/PCI grant/request sideband signals offered by some PCI chipsets of the time, in order to achieve DOS compatibility for their Sound Blaster AWE64-variant PCI sound cards.

AudioPCI supports OPL features; however too fast CPU (for example Pentium 4 2.0 and faster) would break OPL-related sounds (for example MIDI).

Part of the deal when Ensoniq was purchased by Creative Labs was to integrate the AudioPCI DOS driver into the upcoming Sound Blaster Live!.

Creative added Sound Blaster 16 emulation to the driver and removed the Ensoniq SoundScape support.

Resampling means lower sound quality, worse synchronization and possibly higher CPU utilization.

The chip was also a PCI bus master device that was designed to provide high-speed access to system RAM and resources, for sample synthesis data and effect processing.

The chip was capable of spatializing all audio automatically, but still required DirectSound3D usage for specific localization of sounds.

The CT5880 chip is a relabeled ES1371, may be found on some cheap cards i.e. SB Creative VIBRA 128 PCI.