compared to an aftermarket deck
am i gonna notice huge sound changes.
like will my 12's pump better

 

Yes it will sound better once you replace your Bose deck

 

aftermarket headunit will sound much better, a very very noticeable difference. I struggled with that for a LONG time, b/c I hated having bose run my subs... bose sounds great, but the subs suck with it. I got the conversion box, the PAC sni-35 box, which helps a lot... but they still suck compared to normal. I finally found the perfect thing. Its called a overdrive made by audio control. All it does is boosts the voltage of the signal back to normal, its adjustable, and finalllly you can get real sound from your subs. The best 100$ I spent on my system, by far!!!

 

The Audio Control Overdrive processor adds a gain stage in the preamp signal voltage to reduce noise in your system and increase the dynamic range overall of your amplifier in relation to the noise floor. If you are using it as a gain device to make your amp work harder then you are using it improperly, but with a sonic benefit