Everyone knows that for rock music, you don't typically want a clean, pristine organ sound. To "dirty up" your B-3 sound, use the Leakage control. This simulates crosstalk between the tonewheel outputs. As you set the value higher, the separation of the different tonewheels will decrease, resulting in a wider frequency range of the overall tone. This is how you simulate an old B-3 with a million miles worth of gigs in its history. The tonewheels in an instrument that hasn't been regularly (or ever) serviced tend to get leaky or "dolfed" (a term known by B-3 players). Use this to your advantage when you want the ultimate screaming B-3.