If you’re familiar with ‘Sabbath’s live album, Past Lives, then you’ll know where we were going with this pedal - huge, raw, responsive! This circuit is optimized for down-tuning but works equally great for standard tuning thanks to the Range control, which allows you to “customize” the treble-booster section of the circuit anywhere from treble-boost to full-range boost.
According to Mr. Iommi, someone modded his Dallas Rangemaster. “I don't know what he did to it, but it was really good. I used that treble booster on all the early Sabbath albums and put it into the Laney because it boosted the input and gave it the overdrive I was looking for, which amps in the early days didn't have.” Then in 1979 another tech threw it into the garbage, thinking it was crap. Can you believe that?! So no one really knows what was done to it. But based on our experience, it was most likely changing it to be more of a full-range boost and possibly rebiasing it. So that’s what we mean when we say you can “customize” the treble-boost section with the Range knob - you can continuously set it to any input frequency response you want.
Warning: Playing your guitar through the Sabbra Cadabra may result in obsessive riffing and power chording. User discretion is required.