It probably won't effect anything really. The Paradigm's are of such a load that an amp will find them easy to drive. The only way to know impedance for sure is a test whether a review or manufacturer. If the amp runs hot, simply parallel the speakers. This will keep the impedance up. A bridged amp will like this load better anyway. When you bridge, your amp will see an 8 ohm load as a 4 ohm, a 4 ohm as a 2 ohm and so forth.
I do agree with the above poster about deterioration in sound quality when bridged.
I do agree with the above poster about deterioration in sound quality when bridged.