Crystal 4620 4-Channel PCI Sound Card Crystal 4620 4-Channel PCI Sound Card General Features: PCI interface Crystal 4620 chipset Full-duplex playback and recording Built-in 16-bit CODEC HRTF 3D positional audio Supporting both DirectSound 3D and A3D interfaces Stereo Analog Mixing from CD-Audio and Line-in Stereo Digital mixing from Voice, Wave-Table and Digital CD-Audio Mono mixing from MIC Software adjustable volume