Dude, I hate to be the bearer of bad news, but you will be very disappointed with it. I have a 2010 Challenger with the 386 amp and sub-woofer, the option is called Sound Group II. 6 speakers with sub. Same as the Journey, or I thought it would be very close. Ahhh, not even close. In the Challenger, with Bass set a "7" the outside mirrors are bumping, the Journey, at "9" cannot even get the rearview mirror to vibrate. Yeah it's that weak.
If the dealer cannot do anything about it, which I suspect, and I highly doubt Dodge would even bother or tweak the firmware of the system, I'm going to see what the sub P/N is on my Challenger and order one to replace the weak one in the Journey. Also, the Challenger uses the Boston Acoustic speakers. This could also be a factor in the sound. The Journey is just flat across the whole spectrum for a lack of better words.