I have been through about every audio related thread on this site and every other LandRover site known to man. There are tons of opinions, but not much come from facts.

He is what I have come up with so far:

12 Speakers all together.

Front Right and Front Left
{1} 3” Mid Base in parallel with {1} 1” Tweeter per door
6.5” Woofer connected somehow with Rear Door Subwoofers

Rear Right and Rear Left
{1} 6.5” Mid Base in parallel with {1) 1” Tweeter per door

Rear DoorS
{2} 6.5” Subwoofers connected somehow with Front Door Woofers.

Head Unit
Harmon Kardon Unit with 6 Disc CD Changer under Front Driver Seat.
All speaker output connections go to Harmon Kardon 5 Channel Amplifier under Front Passenger Seat.

Amplifier
Harmon Kardon 320 Watt @ 4 ohms 5 channel Amplifier with High Level Speaker inputs

Notes:
2 Rear Door Subwoofers AND 2 Front Door Woofers connected together and on one Amplifier channel. All Subwoofers are 4 ohms.

Questions:
If all 4 Woofers are 4 ohms and connected together, how are they ran. Are two in Series and then the two series paralleled together? If so, which two are in a series circuit? Would that be a total of a 4 ohm load?

If the Mid Bass and tweeters in each door are 4 ohms each, and are in parallel, wouldn't that be a 2 ohm load, which is more demanding than the 4 ohm maximum of the amplifier?

How Does the DVD/Video system connect into the Harmon Kardon head unit?

Everybody seems to agree that changing out the Head Unit is the best upgrade for Sound quality and power. How is this true if all of the OEM Head Unit output is ran straight to the Amplifier. Wouldn't the Amplifier dictate Sound Quality and Power? Wouldn't the first best option be sound deadening the doors, replace original drivers with 10-75watt drivers. Then you have good drivers that can handle the second option which would be to replace the amplifier and possibly the head-unit.