SCSP

Yamaha SCSP

Overview

The Yamaha SCSP, or Saturn Custom Sound Processor, is a highly integrated digital sound processor developed by Yamaha for the Sega Saturn. It is one of the most advanced sound systems found in a fifth-generation game console.

The SCSP combines programmable PCM sample playback, FM synthesis, mixing and a dedicated digital signal processor. This allowed the Sega Saturn to produce a much more sophisticated mixture of sampled and synthesized audio than earlier Sega hardware.

Technical characteristics

• Manufacturer: Yamaha
• Model: YMF292
• Type: PCM / FM sound processor
• Sound generators: 32
• Modes: PCM and FM synthesis
• Sample rate: 44.1 kHz
• DSP: Integrated programmable effects DSP
• System: Sega Saturn

PCM sample playback

The SCSP provides 32 sound generators that can operate as digital PCM voices. Samples are stored in external audio RAM and can be independently pitched, enveloped and mixed.

This architecture allowed games to use realistic instruments, percussion, speech, environmental effects and other recorded sounds.

FM synthesis

In addition to PCM playback, the SCSP can use its sound generators for FM synthesis. This gave developers access to both sample-based and algorithmic synthesis within the same audio processor.

The generators can also be combined to create more complex FM configurations, making the SCSP considerably more flexible than a conventional sample playback chip.

Digital signal processor

The SCSP also incorporates a programmable DSP used for audio processing and effects. It can perform operations such as mixing, delay and reverberation, allowing games to create spatial and environmental effects without relying entirely on the main CPU.

Tracker relevance

The SCSP is an important tracker-era sound system because its architecture combines many of the techniques that became common in computer and console music during the 1990s: PCM samples, envelopes, programmable pitch, multichannel mixing and digital effects.

Its large number of sound generators also made it particularly suitable for complex arrangements containing many simultaneous instruments and sound effects.

Historical importance

The SCSP represents Sega's move toward highly integrated digital audio hardware. It provided the Saturn with a flexible sound architecture capable of supporting both traditional synthesis and CD-era sample-based production.

It was also used in several Sega arcade systems, extending the architecture beyond the Saturn itself.

Related soundchips

• Yamaha YM2612
• Yamaha YM2151
• Yamaha YM2608
• Yamaha YMZ280B
• Ricoh RF5C164
• SegaPCM

Further reading

• Yabause SCSP Documentation
• Yamaha YMF292 / SCSP