Briefly auditioned the YYZ and have an original VT Bass pedal. IMO, the two are not very similar sounding. The VT seems to have more inherent (Ampeg) coloring, whilst the YYZ seems more neutral. By 1-2:00, the VT is getting pretty aggressive in the upper midrange. That sort of tone might be something you can approximate using the tight button. But nothing beats trying it out for yourself!