Crystal Semiconductor
Crystal Semiconductor was an audio mixer/DSP chip company. Founded in 1984 and based in Austin, TX, they focussed on analogue to digital converters and telecoms ICs before moving into PC audio in the early 90s. Their codecs and sound controller ICs were employed on a large number of sound cards during the DOS and early Windows era.
They were acquired by Cirrus Logic in 1991 who had produced some of the highest quality audio codecs mainly used in home theatre receivers. They retained the Crystal branding, marketing the Crystal codecs and audio controllers as Cirrus Logic's budget line. All these chips have the prefix "CS" (as Crystal had used before their acquisition), sold alongside Cirrus chips prefixed "CL".
Generally speaking, Crystal codecs are considered of much higher quality than those of their direct competitors, Analog Devices, whose codecs should largely be avoided.
Here is a list of their most prolific audio codec and audio controller ICs in chronological order. Click on a link to go to more specific information on each one:
| Part # | Released | Bus | Comments |
|---|---|---|---|
| CS4215 | 1993 | ISA | Codec and DAC only (requires separate FM synth chip), “Mwave”-designation |
| CS4216 | 1993 | ISA | Codec and DAC only (requires separate FM synth chip), “Mwave”-designation |
| CS4248 | 1993 | ISA | Codec and DAC only (requires separate FM synth chip), pin-compatible with CS4231 |
| CS4231 | 1993 | ISA | Codec and DAC only (requires separate FM synth chip) (considered the best for its time) |
| CS9203 | 1993 | ISA | GM Wavetable synthesizer |
| CS4232 | 1995 | ISA | Crystal's first proper sound controller/Codec chip (requires separate FM synth chip) |
| CS4218 | 1996 | ISA | Codec and DAC only (requires separate FM synth chip) |
| CS4236 | 1996 | ISA | Controller, Codec and DAC, “CrystalClear” 3D audio |
| CS4235 / CX4235 | 1997 | ISA | Controller, Codec and DAC, “CrystalClear” 3D audio - buggy embedded FM from their CS4239 separate FM chip attempt. |
| CS4237 | 1997 | ISA | Controller, Codec and DAC with CrystalFM. As CS4236 but with SRS instead of “CrystalClear”. Sometimes found coupled with CS9236 wavetable chip. |
| CS4238 | 1997 | ISA | Controller, Codec and DAC. Same as CS4237 but with QSOUND surround |
| CS9233 / CS9236 | 1997 | ISA | GM Wavetable synthesizer with reverb/chorus effects |
| CS4280 / CS4281 | 1998 | PCI | Controller, Codec and DAC. “CrystalClear Legacy Support” |
| CS4297 | 1998 | PCI | Controller, Codec and DAC. “CrystalClear SoundFusion” 3D |
| CS4610 / CS4611 | 1998 | PCI | Controller, Codec and DAC. “CrystalClear SoundFusion” |
| CS4614 | 1999 | PCI | Controller, Codec and DAC. |
| CS4622 / CS4624 | 2000 | PCI | Controller, Codec and DAC. “CrystalClear SoundFusion PCI Audio Accelerator” |