The Electro Harmonix Nano Bassballs Twin Envelope Filter effects pedal has everything you loved about the original Bassballs in a pocket size. The human vocal-like sound of its two sweeping filters gives bass a strong presence under leads, or a commanding quality when out front. The resonant frequencies are engineered solidly into the full range of the bass guitar's strongest harmonics. Bassballs will respond to every bass note. The sweep is widely variable, and harmonic enrichment is available with the distortion switch.

The Nano Bassballs comes in a small, die-cast case with rounded corners, saving valuable pedal board space. The footswitch selects your original signal or the filtered signal as the Bassballs output. The range of the filters upward sweep in pitch is set by the interaction of instrument volume and the sensitivity control. Both stronger attacks and higher (clockwise) control settings increase the sweep range. Low volume and low sensitivity settings will create little or no sweep, and Bassballs will only provide a small boost in its lowest frequencies. In its upward position, the fuzz switch introduces additional harmonic enrichment that accentuates the filters action. The sensitivity pot also serves as a volume control for the fuzz, also increasing in the clockwise direction.