The DiMarzio D Activator Bridge Humbucker has been carefully designed to bring the sound and tonal characteristics of active pickups without the disadvantage of lowered dynamics and the need for a battery. Great for heavier music like Rock, Metal and punk, the D Activator remains versatile. Incredibly harmonic rich and hot to give you that ultimate gain! The D ActivatorTM bridge has an enriched harmonic quality and the notes want to sing. Both the D ActivatorTM neck and bridge pickups were designed to eliminate the sterile edginess commonly associated with active pickups. The D ActivatorsTM use coils tuned to different frequencies. The idea is to shift the resonant point of the pickup to the frequencies of the harmonics that you want to accentuate from the guitar.The D ActivatorTM bridge pickup is about 25% louder than the D ActivatorTM neck. Since DiMarzio was developing both pickups from the ground up as a set, they adjusted the volume levels on the pickups so they are balanced. That way when you switch from the neck to the bridge, you don"t hear a drop in volume, another common problem with active pickups. Recommended For: Bridge Tech Talk: An interesting fact about the most popular active bridge pickups is that they aren"t incredibly loud. Instead, they have a strong, focused attack that hits the amp very hard and makes them "feel" more powerful than they actually spec out to be. This is an important characteristic that DiMarzio needed to capture with the D ActivatorTM bridge pickup. They also wanted to avoid the limiting effect that can occur with active pickups when they are played hard. DiMarzio"s pickup is passive with a lot of headroom, and it responds quickly and accurately to changes in pick attack. A hard pick attack doesn"t cause the signal to flatten out, and picking more softly or rolling the volume control down lets the sound clean up naturally. Like all passive pickups, D ActivatorsTM require controls with a minimum value of 250Kohms. 500K is the standard