Take one of the black wires and shove it Into the EarPods port on your new iPhone. Keep shoving. No, more. Okay. Now, turn on the iPhone. See if you can control the volume.

Actually, there are two of each because you system probably has stereo in each room. You need to go to radio shack and seek help. You will need an amp, a small stereo one, but one big enough to power all your speakers, into which you will wire the red and black leads. (One provides the signal, the other creates the circuit). Once you wire the amp, you need an input device that will accept either the fat plug from iPods, or the smaller new connector.

Given how inefficient thoses wired speakers were, it is likely that your fidelity would be far higher with wireless speakers that are extremely efficient. Sound had come thousands of miles in the last decade. Although a couple of really good speakers, a clean tube amp, and a round disc they call vinyl (be careful, it has delicate grooves on each side) could and does make incredible sound.

http://www.amazon.com/Denon-AVR-X1000-5-1-Channel-Networking-Receiver/dp/B00CALM2JY/ref=sr_1_20?s=electronics&ie=UTF8&qid=1405802697&sr=1-20&keywords=denon+ipod

You might be able to clip the ends of a 3.5mm to RCA cable and get it to work but the sound quality/levels would likely suck.

Especially for you posters who took the time to reply. Your comments were very helpful. So ....not really having the money right now to get an amp and separate receiver with a 3.5 mm or USB input, I simply bought two monster speaker cables with pin type ends, ran them into the wall unit and the the other ends into the old kenwood stereo. Voila! The whole house speakers play what's on the stereo. Granted, I can't risk pushing the volume or put the speakers through their paces, but they DO work and the sound is fine for background ambient music in each room. I think I will save up for the amp and receiver with a USB input. Then the iPod or I pad music will go straight it. My research shows that some of the bluetooth receivers are good but many not. But very few issues with simple USB connected receivers. Your assistance is very appreciated. Thanks.