Originally Posted by Peke
If and when your bass is passive then use passive input.
The so-called "active" input has a pad on it which cuts your input levels. This is ONLY useful when the amp input stage is clipping (distorting) because your signal is too strong.
In the early days of active basses, a lot of them had very high output--so amp makers added the padded input, and labeled it "active".
Regardless of whether your bass is active or passive--and regardless of whether you use any pedals--the only time to ever use the active input is if your signal is too strong, and clipping the amp.