I'm not a future producer or anything I just really enjoy a good sounding pair of speakers. I'm looking to buy the Yamaha HS50M but I see that it has XLR inputs. I just want to know how I can hook them up to my pc. I've seen some dual XLR cables to 3.5mm. But I've read that you need an amplifier of some sort. So my question is can I just purchase this dual XLR to 3.5mm or do I need the amplifier to make it work. Thank you for helping out a complete noob.
Providing that the line or headphone out from your computer is clean, you do not need a preamplifier or amp. You also do not need to use the XLR inputs as that Yamaha monitor has 1/4" inputs, too. All you wil need for basic hookup will be an 1/8" stereo TRS to dual 1/4" TS (Y or insert cable). http://www.sweetwater.com/store/detail/CMP159/
If you want to be a bit more esoteric, audiophile, or the line/headphone output isn't as clean as you want, you'd then want to look into a seperate digital-to-analog converter (DAC). Some "audiophiles" get DACs with headphone amps built-in, so they just refer to them simply as "amps" which may be what has led to your confusion.