Neutrino V2 Optocoupler Envelope Filter / Auto Wah pedal Neutrino Envelope Filter V2 Our Best Sounding Envelope Filter EVER! Improved Note Tracking Upgraded Components External Output Vol. Control Meet the NEW Neutrino. Our best sounding Envelope Filter EVER. Whether you’re in a jam band or playing funk, the Keeley Neutrino V2 delivers incredible vocal-like tone. Keeley has engineered a power supply voltage-doubler so you maintain the highest headroom for your tone. 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. The Keeley Neutrino V2 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.