The Keeley Neutrino V2 is an amazingly toneful and compact form of the classic opto-coupler envelope filter. The Neutrino takes your guitar playing and creates an automatic wah sound based on your pick attack! Envelope filters or auto-wahs as they are often called, sound and react best when they are opto-coupler based. The opto-couplers used in the Neutrino are particularly smooth, giving you an amazing vowel-like tone. The Keeley Neutrino gives you 3 filter ranges, 2 directions, 2 ranges for the frequency center and a Peak control. Plus, an incredibly tough build means it will last for many decades to come.
 
Features
Envelope Filter and Auto-Wah for guitar, bass and keyboard
Peak Control: Sets how much “quack” there is, or how smooth you roll
Filter Selector: lets you choose between 3 types of filters: High,  Low, and Band Pass.
Range Switch: HI or LO.
Direction Switch: Up or Down
True-Bypass, 9 VDC, 25 mA, 100% analog and made in the USA.
 
Stock phots of product. 
 
UPC: 810026440083