You can add an I pod dock and a Sirius with its dock to your existing Marantz if you have two available inputs.
You will need a separate Sirius antenna either way. I use to install lots of them and did not find much difference in antenna's however you may find the nearest window does not face the correct way for reception. It depends on where you live and if you are in a big city that has terrestrial broadcast as well as satellite.
OTOH, the 1504 has M DAX which is a program designed to restore a lot of the musical information that was lost when it was encoded to better "fit" into I Pods and satellite radio.
If you want your MP3 type files (I pod and Sirius) to sound very close to your CD sound quality than I strongly suggest you check out the M DAX processor in the 1504.
HTH
You will need a separate Sirius antenna either way. I use to install lots of them and did not find much difference in antenna's however you may find the nearest window does not face the correct way for reception. It depends on where you live and if you are in a big city that has terrestrial broadcast as well as satellite.
OTOH, the 1504 has M DAX which is a program designed to restore a lot of the musical information that was lost when it was encoded to better "fit" into I Pods and satellite radio.
If you want your MP3 type files (I pod and Sirius) to sound very close to your CD sound quality than I strongly suggest you check out the M DAX processor in the 1504.
HTH