Step 1: Is it still working?
First things first, you need to check whether or not your old audio system is still in working condition. For simplification, we will assume that your audio system runs on AC power (which means, you can plug it directly to the plug points at home), and that it has some sort of input port or connectors to receive audio signal. Most audio systems use either a 3.5mm jack or RCA jacks as line-in (audio input). However, some may use the larger 6.5 mm audio jack or an optical cable such as Toslink. You will need a connector according to the jack in your audio system — it’s ideal to invest in a good quality 3.5mm to 3.5mm/RCA/6.5mm cable with gold-plated connectors. Locate the line in port and connect your portable music player/phone to the device using an appropriate cable (can be bought online, if not available). If you can hear sound being played out loud and clear (slight interference would do), your audio system can be easily refurbished.