You can brute force implement biquads, though Spin ASM includes built in filter instructions that implement a 1 pole filter in 2 instructions, while the most common type of resonant filter you see throughout the examples is a state variable 2 pole structure that takes about 6 or 7 instructions and has control inputs for frequency and Q (if you need that). Biquads by comparison are relatively a pain, however there may be some advantage to one approach or the other (e.g. filter accuracy, resistance to overload or stability at higher filter center frequencies near fs/2, which probably does not apply to a cab sim).