I have a Pioneer A-209R Hi-Fi amplifier which has RCA-inputs (one of them is phono). I am wondering what's the best way to connect my MP6 to the amp. Should I use the mini-jack to RCA cable to connect headphone out or use jack to RCA to connect the line out?

Sorry for the noob question but I am not quite familiar with audio stuff, impedances, etc. I am afraid that headphone out is already amplified and that may be too high a signal for the amplifier. On the other side I've made recordings from the line out to the PC with some home-made cable and there was a noise in the recording which makes me think it may not be a matter of just simple cable? I don't need to make recordings though, I mentioned it just for information. I need to be able to play my piano to other people but I don't want to spend money on additional equipment and dedicated keyboard amp/speakers. I just need an acceptable connection to my home stereo amp which I will use rarely

If your MP6 has line outputs, use them.
Connect them to the line inputs (or aux inputs) of the amplifier.
(Do not use the phono input.)

If I solder myself such a cable (a pair of mono jack to mono RCA), are there any specific considerations I should take in mind? I am not sure if I have seen this combination readily available.

It's not an uncommon cable. Basically anyone who uses and digital piano with an amp needs one.

http://www.amazon.com/Hosa-Cable-CPR201-...words=ts+to+rca

Thanks!