Ensoniq ES-5506 OTTO

=ENSONIQ ES-5506 - "OTTO" 32-Voice Wavetable Oscillator Chip=

The Ensoniq "OTTO" was used in many implementations of wavetable synthesizers. Musical instruments and PC sound cards were the most popular uses. For example, the chip was used on the Ensoniq Soundscape S-2000, Soundscape ELITE, and SoundscapeDB daughtercard.

OTTO was a sample playback synthesizer. OTTO was capable of altering the pitch and timbre of a digital recording, and was capable of operating with up to 32 channels at once. Each channel could have several parameters altered, such as pitch, volume, waveform, and filtering. The chip was a VLSI device designed to be manufactured on a 1.5 micrometres double-metal CMOS process. It consisted of approximately 80,000 transistors. It was Ensoniq's fourth generation of their audio technology.

The major features of OTTO were:

*Real time digital filters
*Frequency interpolation
*32 independent voices
*Loop start and stop positions for each voice. Bidirectional and reverse looping
*Motorola 68000 compatibility for asynchronous bus communication
*Separate host and sound memory interface
*At least 18-bit accuracy
*6 channel stereo serial communication port
*Programmable clocks for defining serial protocol
*Internal volume multiplication and stereo panning
*A to D input for pots and wheels
*Hardware support for envelopes
*Support for dual OTTO systems
*Optional compressed data format for sample data
*Up to 16 MHz operation

References

* [http://web.archive.org/web/19980214042324/www.ensoniq.com/multimedia/semi_html/html/otto.htm "Ensoniq Corp. Web Site"] by Ensoniq Corp., Semiconductor Information Pages, 1998, retrieved December 25, 2005