I've been messing around with a KR Megavibe, trying to figure out how to make it do a "cancel" feature as well as the stock true bypass switching.
From looking at the schematic here, it looks like the cancel feature is simply bypassing a 47k resistor to ground:
http://www.geofex.com/article_folders/univibe/univtech.htm
I've tried to bypass all the several 47k resistors inside this thing, but can't make it cancel out as it should. Has anyone tried this successfully?
I want to do this in order to have the Uni-Vibe preamp running in the chain when I want it, but without the effect. I believe that preamp sound to be a significant factor in Hendrix' BOG tone (yeah, I know...another one chasing it...).
One further question: when you turn down the intensity, the effect eventually "freezes" and the light to the bulb appears to be turned off. However, at this setting, the sound appears quite severely altered from stock bypass. Is this setting the "same" as with the vibe in "cancel" mode on an original? I also notice that the tone alteration is much less severe in vibrato mode than in chorus mode.
Lastly, according to Stuart Castledine (www.wah-wah.co.uk), there were several small differences to the early Uni-Vibes. I've also heard many people say that different vintage Uni-Vibes affected the sound in cancel mode to a varying degree. Could this be one of the reasons that the BOG sound is rather unique in the Hendrix catalogue?
From looking at the schematic here, it looks like the cancel feature is simply bypassing a 47k resistor to ground:
http://www.geofex.com/article_folders/univibe/univtech.htm
I've tried to bypass all the several 47k resistors inside this thing, but can't make it cancel out as it should. Has anyone tried this successfully?
I want to do this in order to have the Uni-Vibe preamp running in the chain when I want it, but without the effect. I believe that preamp sound to be a significant factor in Hendrix' BOG tone (yeah, I know...another one chasing it...).
One further question: when you turn down the intensity, the effect eventually "freezes" and the light to the bulb appears to be turned off. However, at this setting, the sound appears quite severely altered from stock bypass. Is this setting the "same" as with the vibe in "cancel" mode on an original? I also notice that the tone alteration is much less severe in vibrato mode than in chorus mode.
Lastly, according to Stuart Castledine (www.wah-wah.co.uk), there were several small differences to the early Uni-Vibes. I've also heard many people say that different vintage Uni-Vibes affected the sound in cancel mode to a varying degree. Could this be one of the reasons that the BOG sound is rather unique in the Hendrix catalogue?