I use an old iPod Nano (remember those?) as my break in source, playing a mixture of music, signal sweeps and white noise MP3s (XLO has one available for free download) on auto repeat for a week. If you have a FM tuner laying around that works too but I like being able to make a playlist of things.
If you are reasonably handy you can terminate the cables with a load resistor around 100 ohms to get a lot more current through the cable. You don't even need to solder or use jacks, test leads with alligator clips will do. If I need more power I use a Dayton T-amp and a 4 ohm load resistor. This stuff is not that complicated and you do not need to buy any fancy discs or equipment...
If you are reasonably handy you can terminate the cables with a load resistor around 100 ohms to get a lot more current through the cable. You don't even need to solder or use jacks, test leads with alligator clips will do. If I need more power I use a Dayton T-amp and a 4 ohm load resistor. This stuff is not that complicated and you do not need to buy any fancy discs or equipment...