There was a guy that my Dad used to play with when I was just a little kid (late 50s early 60s) , who had a pre war Martin with a red spruce top. Even as a little know nothing kid , l could tell how remarkable it sounded. All you need is a halfway decent set of ears
. The guy was actually a hack player but his instrument was absolutely amazing
. Louder, brighter and just remarkably resonant compared to everyone else who were playing Gibson dreadnaughts and arch tops (not a slouch in the bunch). It was not just the construction of the Martin but the materials, specificly the red spruce top. The war caused a shortage of red spruce, and depending who you talk to, it takes a red spruce 50 to 75 years to mature and make a fine resonant instrument. So, starting right about now there is a lot of red spruce that's getting ripe and ready to make some first class acoustic instruments
. I expect that in the next few years you're going to see some acoustics that will sound like nothing that most have ever heard.
I remember my father saying on many occassions, " It's a damn sin for an ass like that to have such a beautful sounding guitar ".
Rick