Speaking of soldering irons, the IEEE Spectrum website has
an article on how to upgrade your cheap affordable DVD
player and make it work like one costing thousands more.
Before I get too far, note well that these modifications are
not for you Sunday solderers out there. You must make
potentially dangerous modifications to the power supply and
other high voltage areas of the DVD player. Some of these
areas can hold an electrical charge large enough to cause
injury or death for months after the unit has been unplugged
from the wall outlet. Hence, unless you know what you are
doing, do not even think about trying to make these
modifications. You have been warned. Proceed at your own
risk. The door is a jar.
That said, the changes consist mostly of switching out cheap capacitors with high quality units. By making these changes, the author of the article says he obtained cleaner, better sound and truer image colors from his DVDs. These claims must be taken with a grain of salt since no double blind, scientifically controlled studies were done. He didn't even try to measure, using various calibrated test instruments, the alleged better sound and picture. But if you really like modding stuff, and are qualified to make these changes, this could be your cup of tea.