Audio Systems: Home Stereo question, speaker volume control, polk audio speakers

Question
QUESTION: I have a house with a main room , it has a set of in wall polk audio speakers , I power those with a Yamaha RX730 ( yes it is old tech but works great)
I have 4 other rooms that have speakers . Each set has its own speaker volume control.  I beleive these are polk as well. all the wire from those run into the wall behind the amp
I am trying to figure out a way to make this work
I want to run sound to them but only have speaker A and B on my amp and I found that I have to turn the main room up too loud in order for the other speakers to be heard ( even with the  individual ) volume controls to full. What options do I have , I have a record out setting on my amp that I think will feed the source  but to what?? another amp? If so what kind and how does one run 4 sets of speakers , twist all the wires into a right and left bundle? That is what I am doing now, dont know if that is a good idea
Is there somehow I can make this system work, or if you were startimg from scratch what  would you do?

ANSWER: First of all, it's not a great idea to have all of the speakers tied together like you have it. This is because the combined impedance of the speakers may not match the range of your receiver/amp. This can do bad, expensive things to amplifiers.

What you need is a distribution amplifier. This would take a signal, and send it down the individual lines without overloading the amp.

Look for something along the lines of this:
http://www.amazon.com/Niles-VCS-HUB8-Speaker-distribution/dp/B00024BLK2

This should give you a good start. Since I don't know the particulars of your system, this is about as far as I can comfortably lead you to. I hope this helps!

---------- FOLLOW-UP ----------

QUESTION: great, help me understand what this item does , so how would this connect to the amp output and would that then send equal inputs to each speaker set so that the main set is not louder than the rest?  Do I need another amp inbetween?
thanks so much

Answer
It's pretty simple - if you don't understand the physics of what's happening, don't worry. It takes in the L & R speaker outputs from your receiver. It then distributes that power equally to the speakers/volume controls through your rooms (up to 8). You won't need an additional amp.

Here's the manual for the device:
www.nilesaudio.com/images/PDF/VCSHUB8_manual.pdf