[Radioroslyn]

Something else that will improve the sound is using a backwards output or filament transformer to match the impedance. Without it you are driving an input of 500,000 ohms with 8 ohms. Not a good match at all. From the ipod take the two center conductors and connect them together. Take the two shields and do likewise. Take the two connection (one the center connection and two the shield connection and connect them to the 8 ohm or the low voltage side of your transformer. Connect you radio to the plate side of the output transformer of the 115vac side of the filament transformer. You will notice much more volume and better tone.
Terry