Im installing a sub with an amp to my 14 maxima with the stock radio. Question can it be installed separate from the stock speakers so i can use a bass *** to control the sub.

 

Yes. Most amps will have an remote control **** that you can plug into it and run under your dashboard, or wherever. Whatever is attached to that amp is what can have their levels adjusted by the remote control, so I'm assuming you're just leaving the stock speakers attached to the radio outputs. So if you just wire your sub to the amp, only the sub bass level will be adjusted with the remote.

 

This was the first mod to my 7th gen. It will really help your system as the bass is pretty anemic in our cars. Cotozic explained it well.