Last year I purchased an audio cable to play music on my iphone through an old 50's mono radio. I noticed that some songs didn't sound the way they should and it was pointed out that music recorded in stereo won't sound proper when played on a mono radio. I then purchased another cable that, when in conjunction with the original cable, made the music seemingly play in stereo through the old radio (or at least the songs were no longer 'missing' guitar parts, etc...). I have since moved and can't find these cables. What were they? Please help!