Check the listing for details. Electro-Harmonix Micro Q-Tron filter. Condition: New. Listed at 112.50 USD. Electro-Harmonix Micro Q-Tron filter The Electro-Harmonix Micro Q-Tron filter. FREE shipping in the USA! Player controlled dynamics moving a precise multi-mode filter with a sweet adjustable Q makes the Micro Q-Tron an amazing envelope follower. The Micro Q-Tron is identical to the Mini Q-Tron, but in a more compact housing. Choose from LP (Low Pass), BP (Band Pass), or HP (High Pass) to determine what frequency will be the filter will pass. Features:- True bypass - Drive control sets sensitivity and filter sweep range - Selectable low pass, band pass or high pass filters - Q control sets the filter's bandwidth from smooth to funky - Tough and compact die-cast chassis - 9-volt battery included - Optional 96DC-200BI power supply available Video courtesy of Electro-Harmonix