20 Most Recent Pioneer SX-255R Receiver Questions & Answers

yes you can

You need to hook it up to another analog input other than the phono input. The record player has a built in preamp, and the receiver's phono input has a separate preamp for non-amplified players. You cannot have the two hooked to each other.

Looks like a scanned version of the user manual is available on
http://www.pioneernz.co.nz/Site/Pronto/Files/user_manuals/SX255R%20USER%20MANUAL.PDF

good luck to those who have been on this post

Power source harmonics. Or its power supply regulation. Check also if input line is touching something.

You should have an headset jack on the computer. This is the easy way I have found to play music on other systems.

Well get yourself a digital volt/ohmmeter and trace them out. Plus and minus are not absolute. Just don't touch one to the other with power on. Reversal of them on a given speaker only changes its phasing. Web search: speaker phase test

With no attachment to any electronics - short the pair at one destination together ONLY for this test. Go back to the source end and use the ohmmeter to see which two conductors they represent. Mark them. Disconnect the short. Repeat for other speakers.