travel outside the analyzed borders and it sounds how it does not suppose to sound.

If, I understand nebula correctly the only correct way to aquire distortion. is if the preset designer drives the input of his hardware chain and makes sure the returning signal does not clip on his interface.

Having that said, I use nebula on my master.
and i like henry olonga his presets the most

 

You can drive Nebula at the input yourself and get some nice phat/saturated sounds. But full on distortion it can't really do yet properly, even if the preset designer samples it, it kinda ends up sampling the frequency and phase response, without being able to capture the actual distortion itself.

 

Send an hot level to pink compressor and you'll see.

 

A 99% Nebula and Acqua mix.