I'm upgrading my speaker system to the db501 and db401. The speakers are @ 4 ohm. The question is.... wiring the speakers in parallel will drop the ohm load to 2 ohm which may damage the output transformer in the radio, but will allow the speakers to stay in phase. If the speakers are wired in series, the ohm load will now be at an 8 ohm load which is safer but the speakers will be out of phase with each other. Does anybody know the output ohms load of the radio? In phase or out of phase isn't as important as the load of the speakers hooked up to the radio. Being a musician I'm familiar with the hook ups if I have the numbers. This may not even be an issue. I just don't want to damage the radio.