[mountainmaster]

I have an X20 and an X7 with the current body shapes. They are nylon string guitars, so I am not sure if my comparison fully applies to steel strings.

The X7 is focused in the mid range, as one would expect from a parlor size guitar. The X20 has more bass AND more treble. It also has more complex harmonics.
My X7 sounds very dry and direct. I think this is why it appears to be louder than my X20, although I have not been able to measure this. Both are rather quiet instruments though, even for nylon strings.

Edit: I forgot to mention that my X7 has a 24.9" scale length. The current longer scale option for the X7 is 24.5".