I have an altech Lansing subwoofer and two speaker set that I hook to my laptop... I also have an old stereo with amazing spea

[Nanner369]

Help hooking up computer speakers, stereo speakers and making them both work with my computer.

 

[americanaudiophile]

You can split the audio output of your laptop to connect to both the speakers and old stereo.
You wiil need a splitter
http://www.parts-express.com/parts-express-dac-digital-to-analog-converter-%2851-compatible%29--180-999
and a cable with stereo mini plug at one end and two RCA plugs at the other to connect to your old stereo.