For Essence basses or any Alembic Activator system with a low-pass filter.
This prewired switch replaces a single box capacitor on the AE-1 preamp board. Once installed, it allows you to have the familiar 8 dB boost the filter always offered PLUS the option to dampen that boost to near zero for the flat filter response. In a nutshell, if you want to have access to tones with less attack than you have now, you need this simple modification.
After adding the switch to the board, you'll need to drill a hole in the bass, and possibly recess it. It's best if you are able to shield the newly recessed area.
Mounting hardware and instructions are included.
Also available as a 3-position switch with settings of approximately 0/6/9 dB.