Placette RVC

If you drive your amp from the headphone output, naturally you'll need a stereo headphone to two male rca adapter you get these just about anywhere for a couple of bucks.

http://www.ebay.com.au/itm/New-6-5mm-Aux-Male-to-2-RCA-Female-Socket-Adapter-Y-Splitter-Connector-Converter-/291121613799?pt=LH_DefaultDomain_15&hash=item43c8334be7

Or just use the fixed line out with a decent 10kohm passive preamp like the Schitt SYS $49 which uses Alps 10kohm Logarithmic Volume Pot.
http://schiit.com/products/sys

Cheers George

Ok, the minijack to 2 RCA is pretty straightforward, I have that.
My question is rather what happens if I DON'T use a pre-amp (passive or active) and feed the LINE OUT from the DIRECTLY to the amp.

Will the sound go through at MAX volume frying everything in its path and exploding the loudspeakers?
(Well, just exagerating a bit to make my point clearer)

Thx

Depends on the gain of your amp and the output of your source. This is known as the "Bolero Test"
You could try it from the direct line out of your source with no volume at all, but you need to use a cd to see how loud it's going to get, hence the Ravel Bolero cd is ideal as it starts off very quiet and builds so you can then gauge if you are going to blow your amp.

Cheers George