The first affordable multi-tracker. Not as powerful as todays synths, but it can do tricks the others can't, due to it's analog & discrete tracking functionality.
Sequential Circuits Electronic Music Synthesizers
Music Machines: Sequential SixTrak
synthmuseum.com - Sequential Six-Track MIDI Information
Yahoo! Sequential Circuits Six Trak
Turtle Beach Home Page
Pinnacle Project Studio
Disk Space Used by Digital Audio