Re: Different Size Subs?
I used to run 2 8" subs in the parcel shelf and 2 top of the line kicker subs in a massive box in the boot. It works really well.
What you'll need is a 4 channel amp with enough power to run the big subs and it must have a low pass filter on both the front and rear channels.
Then wire the 8" subs on the front left+right channels of the amp (most 8" subs do not need a lot of power to run) and then wire the 2 big subs in paralell-bridged mode of the rear channels.
If your amp is anything like the kicker amp I used to run it will have a frequency adjustment. Set the 8" subs to higher pitched and the big subs to lower pitched. That way you will get buzzing mid bass from the 8's and earthshattering lows from the big subs.
I don't have the 8's anymore but I wish i did, they really did make the sound so much fuller, but if you only listen to dance music there is not a lot to be gained from them. The only way to make sound from a sub in the parcel shelf is to make a new one out of 18mm MDF. The stock parcel shelf is way to flimsy to install anything decent in.
Just like a Tsunami.