Difference between Crutchfield and Sonicelectronix is that Crutchfield is a factory authorized internet dealer for the products they sell and Sonicelectronix is not. So Crutchfield has the backing of the factory and OEM and Sonicelectronix does not. I have dealt with Crutchfield's customer support and it is top-notch, cannot be beat, very knowledgable technicians that bend over backwards to help you and if needed have the manufacturer to ask question to also, I have never had to deal with Sonicelectronix customer support so I have no opinion on them.
