Jmcgrogan2 is correct on how loud the peak sound pressure levels will be with each speaker. However, another thing to consider is how each speaker will sound (i.e. tonal balance), which will vary depending on not only the voltage sensitivity but the nature of the load. For this you need an impedance vs. frequency curve. For instance, many speakers have a combination of low impedance and a highly capacitive phase angle in the mid- to upper bass. If you use a tube amp you will probably run out of current in this region and the sound may become either lean in the bass and/or flabby and boomy in the bass. Since you are using a Classe solid-state amp you probably won't have this issue since SS amps usually have low output impendances, but still it is something to think about.
