i have a jl 300/4

is it possible to leave it in 4 ch mode and just use 2 of the channels at 75w each while leaving the 3/4 ch empty because i dont feel like messing with a rear stage right now

 

Its not going to hurt the amp if that's what you are wondering.

 

Yep thats fine.

 

nah, im worried about it bridging and destoying some expensive a$$ components

 

Im not really understanding what you are wanting to do? If you are just going to use the front two channel and not use the rears, you are fine. You are talking about bridging? Which channels can be bridged? There shouldn't be any way to hurt your components, unless your doing something crazy.