HELP!!!!!! Question About Powering LEDs

So I'm trying to power 70ft of 5050 SMD LEDs. I wanted to make them sync with the beat of the music however, so I bought a separate controller that allows me to do this. I disconnected the wires that went into the original controller and attached them to the new controller which synced to the music. The LED strip barely lit up and I assumed this was because I wasn't able to generate enough power with my 24v power supply. I wanted to test how much voltage the original controller that came with the LEDs outputted to get an idea of the power supply I need to buy. However, when I measured it with my multi-meter I got very confusing results. I got 120v AC when measuring the input, (which makes sense because it's coming directly from the wall outlet) and 0v when I switched it to DC (again this makes perfect sense). When i measured the output voltage of the controller however, I measured 140v DC and 50v when I switched it to AC. How can I possibly get a reading of both AC and DC current? I need to know which reading is the correct one. If anybody can help me it would be VERY much appreciated. Thanks.