TechPowerUp takes a look at the Creative Sound Blaster X4
A quote from the article:
The Creative Sound Blaster X4 is a direct successor to the excellent Sound Blaster X3. This external USB sound card keeps everything good about its predecessor and adds a couple of interesting additions to the mix, most notably SmartComm Kit—a combination of features aimed at improving our online call quality.Creative Sound Blaster X4 Review