Lovely 48++ Yamaha Fs830 Small Body Acoustic Guitar. Today i'm comparing two acoustic guitars, the fg800 vs fg830. The fs model body is 10mm slimmer than that of the fg body, offering increased comfort and. The fs830 concert acoustic is not only smaller than a traditional dreadnought but also thinner, making it ideal for young players. The fs830 offers rich overtones, greater depth and improved sustain thanks to the rosewood back and sides and special bracing.