My stock bose is suffering from SBDS. I didn't really notice until I replaced all the stock speakers with kappas and went crazy with a roll of raammat.

Suddenly the blose sounds like bose and all is good. That is to one particular point. It sounds kickass up to and including volume level 22. Go one degree higher to volume level 23 and major reduction in bass output. I know why it is doing it, to not overdrive the stock amp and weak stock speakers. I need to know where it is doing it. Is it occuring in the HU or the amp?

If it's the amp fine, that thing is destined to be ****canned anyway. If it is the HU I'm going to be a wee bit pissed if it is effecting everything downstream.

 

You have experienced one of the biggest reasons to tap into the audio signal before it enters the Bose amp. It decreases bass as you increase the volume. That's also a good reason to replace the Bose amp completely.