The Ernie Ball Expression Overdrive delivers everything from a hint of natural tube-amp-like overdrive and rhythm crunch to searing lead tones. It features settings for drive, boost and tone, with a foot-sweepable overdrive control, making it effortless to go from clean to roaring all-out growl and everything in between.
Boost level adjustment
Foot sweep heel down—original signal (no effect)
Foot sweep toe down—overdrive and boost level (maximum effect)