The Mole - Bass Boost

The Electro-Harmonix Mole is a bass booster designed to emphasize low frequencies while increasing overall signal level. Based on a classic EHX design, it provides up to 20 dB of low-frequency gain, with its center frequency shifting from approximately 400 Hz toward 200 Hz as the volume is increased. The single control adjusts the amount of boost, allowing it to add subtle low-end emphasis at lower settings or a stronger bass-heavy boost at higher levels. The Mole features true-bypass switching, a compact die-cast enclosure and can be powered by a 9V battery.