Running Two Amps

I have a question for those running two amps. So I'm thinking of running two amps and I need some advice and feedback to what I'm considering.
I have one amp currently powering two Kicker Subs and I want to run two more Kicker subs so I have another amp to add. I wasnt sure if I can run the second amp off the same power cable? If so, would I be purchasing a splitter terminal to start a pair of power cables that will then feed two amps. I would have those voltage storing cells on each cable before it goes to the amp. I forget the proper term but I was looking at power cells that store voltage and wasn't sure if that was a solution to have two of them, one for each amp so it can store the power and save my battery.
Anyhow, I need to be schooled on this... Thanks.

You're going to need to run at least 4 AWG cable from the battery to a distribution block (splitter) in the back of the car. Then you can run 8 AWG cable from the D-block to the amp. Be sure to include a fuse near the battery. This setup will handle most systems unless your amps put out 1000W or more. Then you would want to use even larger guage power cables.

The voltage storage cells you refer to are called stiffening capacitors. Whether they help or not is debatable. In certain cases they can help. The real fix for the problem is a high output alternator.

Yea, I wasn't sure if those capasitors helped and I haven't heard much about them. Thanks for specifying what size guage I need to run. I'll have to check and see what gage I already have under the hood. I already have a fuse by the battery so I'm all good there.
So are you running a higher Alternator. If so, which one and how many amps? Even with this bridged generic amp I'm getting drain as I can see my volt meter dip and my headlights dim.

Right now I'm still using the stock alternator. I'll upgrade it one day but for now it's not all that high on my "things I need to do" list.