This instrument was designed to be a powerful concert instrument with rich tone through a number of innovative features.
The primary unique feature is the molded, thick double back in combination with the double top soundboard. The back is 4.5 mm thick with Nomex laid up in a mold. After curing it becomes very stiff and requires no back braces or kerfing. The effect on tone is beneficial for a variety of reasons not the least of which is that the elimination of the back braces seems to improve the way in which air movement behaves inside the body. Acousticians might call this an effect on standing waves but whatever the technical reason the result is a very smooth, rich sound.
I had originally thought that the back would be very stiff resisting the vibration of the string energy thus causing the soundboard to work harder. I am sure it does somewhat but to my surprise this very stiff and rigid back still gives feedback to the guitarist when being played. I think that is a good thing
I have found that doubling the sides of the guitar to about 4mm is helpful for power and structural reasons. Therefore the Quattro has sides that are even a step further at 6mm utilizing a lamination of rosewood sides and wood filler.
Part of the design philosophy is to make a very stiff body similar to the Australian school guitars but without the weight due to the use of Nomex in the back. To be sure the guitar is heavier than a traditional guitar but not to any objectionable amount. In the classical position the guitar‘s weight is held by the lower body, the slight additional weight is of little consequence.
The acoustic port is a terrific addition to the classical guitar as it helps the player to hear his guitar better while having a slight beneficial impact for the audience. However many people wonder how a piece sounds without the port and so the Quattro has an adjustable port which can be opened or closed at the player‘s whim. I have tested the adjustable port at our local guitar society meeting and most people like the port open and others depending on the piece liked to have it closed. In my studio I found that I liked it partially open but that might be because I have grown used to hearing the open port in my other guitars.
The Quattro is a lot of work to make but the powerful, rich tone is worth the effort. Following the uncompromising design objectives the Quattro comes standard with Rodgers tuners and a flight case with pack packer straps, hygrometer, humidifier and airtight seals. Only premium tonewoods are used on the Quattro.