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Zvex Super Hard On

Zvex Super Hard On

Regular price $ 239.00 USD
Regular price $ 239.00 USD Sale price $ 239.00 USD
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This is the perfect preamp pedal. The "Crackle Okay" volume knob is a negative-feedback control styled after classic 60's recording console inputs. (They crackled when adjusted too.) Most vintage guitars suffer from steadily deteriorating magnets in their pickups, since permanent magnets aren't really forever. The Super Hard-On's input impedance is so high (>5 Meg) that it refuses any current flow from your pickup... maintaining the most magnetic field around each string, so you can hear exactly what your pickup sounded like the day it came off the winder. The ouput level can exceed 8 volts peak, and when it finally distorts, the wave is shaped like triode overload, not fuzz. 

It's so transparent no one will be able to tell you're using a pedal. Perfect for making the most of a classic amp and guitar, because it simply makes your guitar bigger and pushes the amp harder, causing natural overload. This sound can be the solution to the 'disappearing guitar' effect you get sometimes on stage when you stomp on your distortion and sound weaker. When cranked, it sounds much louder than a fuzz or distortion under stage conditions. 

Like all Z. Vex designs, current flow is low in this circuit (less than 2mA), enhancing battery life. The circuit board is hand-cut and soldered with the critical component, a BS-170 mosfet transistor, placed in a socket for easy user replacement should it be necessary. Your dealer can provide you with a free replacement transistor upon request. 

The box is hand-drilled using no petro lubricants, and hand painted so that every box is unique. Knobs are Harry Davies, made with the same molds they've used since the fifties. Each effect is hand dated and signed by Zachary Vex. 

WARNING: The very high input impedance of this pedal can cause strange reactions (sometimes mildly pleasant and/or arousing) when used with a vintage 'junk' (read 'cool') guitar. The solution is to simply lower the 'crackle okay' gain knob a little or leave the guitar volume wide open. Each Super Hard-On is unique in it's reaction... you may have to try a few till you find one that perfectly matches a really strange guitar. They are optimised for the major brands. Any problems will only occur at the highest gain settings with an unusual guitar. 

The Super Hard-ON uses a very sensitive transistor, with some early versions mounted in a socket. During 2000, I installed a protection circuit to prolong the life of these transistors and I've seen no failures since. If you have a problem with an older unit, feel free to contact me, or you may purchase transistors inexpensively from 1-800-DIGIKEY where they are sold as part number BS170P-ND. You must follow proper static handling procedures to install the part... write to me for instructions at and i'll set you up. Newer SHO units have a diode protection circuit to keep the transistor from blowing. Please contact for information about updating your older SHO. To protect your SHO's transistor on older units, please turn the unit off before unplugging the cords. On SHO units produced during 2000 and beyond, the battery switching jack has been moved to the output jack closest to the front of the unit (closest to the J. Myrold signature). Please unplug from this jack to preserve battery life.
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