This is one effect I do not have that I am sure I will eventually add.
I owned a few old Fender classic amps when at the time NO ONE
used the tremolo. It was considered corny and dated and showed
up only in movie soundtracks at the time like the first James Bond
flick. But the new pedal versions give you a choice of waveforms
and exaggerated depth and speed. The new Trems are musical not just special FX noises.
It even does an effect that the modulation increases in speed as you hold the note. If you plug a expression pedal into it and control the effect manually.