What are the advantages and disadvantages of active and passive pickups, and why does DAlegria use a preamp on its active basses?
The main purpose of using either an active or a passive pickup with a preamp is the same. The idea is to provide in the instrument’s output a high headroom and low impedance, with 3 basic objectives: – To minimize the effects of the amp’s input impedance on the final sound result; – To diminish the effect of the cables’ capacitance, which causes a “cut” in the high frequencies in passive basses; – To diminish the generation of noise through the cable that connects the bass to the amplifier, since the low impedance signal is less susceptible to this. These objectives are reached with the use of a preamp, providing a high impedance input where the pickup is connected and a low impedance output where the amp is connected. In both cases (active pickup and passive pickup + preamp) the arrangement is the same. The only difference is the localization of the preamp: with the active pickup the preamp is installed inside it, and with the passive pickup + preamp it is located inside the instrumen
