To combine the stability and robustness of carbon fiber with the traditional aesthetics of wood, RainSong has developed SFT:; Soundboard Fusion Technology.

After careful experimentation, they were able to fuse a thin spruce soundboard and a unidirectional pre-impregnated carbon in a single molding step.; The resulting SFT soundboard is a composite matrix that resonates as a single unit, like a solid wood soundboard.; The physical properties of the carbon fiber far exceed those of the thin wood. Hence the SFT soundboard maintains the imperviousness to humidity and temperature 
of carbon fiber.

An SFT soundboard delivers rich crystalline carbon sound subtly colored by wood. There is no better stage than a 12-string to appreciate the qualities of all-graphite construction and Projection Tuned Layering. Rich, loud, clear and balanced, the Carbon/spruce sound is only heightened and made more intense by the complex tones, overtones and sympathetic overtones specific to a 12-string. 

The stability and strength of carbon-fiber compared to wood is very high. As a result, RainSong is able to set its twelve string action low and to design its neck to be thin, comfortable and easy-to-play without fear of structural failure due to the increased tension of six extra strings.

The RainSong N-JM3100 Jumbo 12-String Acoustic-Electric Guitar combines the large-sized sound chamber with lightweight carbon-fiber/spruce construction to deliver extra-loud and deep tone that superbly counterbalances the extra treble strings. 

This is a 12-string guitar that is great for strumming and finger style, full of power and delicacy, and ready to hit the road. 

The RainSong N-JM3100 12-string acoustic-electric guitar is able to stay in tune at concert pitch and to withstand temperature and humidity variations; qualities that every seasoned 12-string player has long pined for.