I have been doing a lot of casual testing with a variety of other drums including vintage Sol, Matthew Smith, all kinds of LP's from all different era's and even Fat Congas as well. They are all on my youtube channel in comparison videos. I can post the links here if people want to see them. Conrad (the builder) say's (something to the effect of) that when you use staves in construction the individual staves each have a different tonal resonance and character, and when you add on uneven surfaces to the equation as well as glue lines, the sound frequencies are bouncing all around the place. When it is one solid piece of wood the tonal resonance is more balanced. I am not a scientist or math guy and I do not know for sure if all that is true or not (it can be argued either way I am sure!) but the bottom line at the end of the day is that they sure sound great to me. I love the combination of fat tone, crispy slap and bass notes even in the requinto! I also own Matthew Smith, LP's, Skin On Skin, Fat, Gon Bops and play with my friend with the full set of Sols.
http://www.youtube.com/watch?v=QuovWghlwZo