The best features of an active pickup, but with no batteries required.
The Book is still being written about what an 8-string pickup should sound like. DiMarzio think it should have a wide frequency response, be very articulate and dynamic, and not be muddy.
The DiMarzio DP820 D-Activator 8-String Bridge Humbucker model is most definitely a high-output pickup, with powerful, focused bass response combined with warm highs and extended harmonic overtones. The lows are just as tight and defined as the D-activator 6 and 7-string models, and the highs are a little smoother with strong attack.