Russian guitar usually differs from the wood in the rest of the neck. The neck joint or heel is the point at which the neck is attached to the body of the guitar. The fingerboard is made of hardwood (ebony or rosewood are common), fitted with metal frets of brass or steel. Fret spacing almost always follows the western twelve tone equal temperament (12-tet) system. The surface of the fingerboard may be flat or curved slightly ("radiused"), although the curve on the Russian guitar is usually somewhat less than that of an equivalent western 6-string guitar. Inlayed position markers are common, and
Eight-string guitar Novax Guitars. Five of the strings are tuned to the standard guitar's upper five (A, D, G, B, E), while three of the strings are tuned to the standard bass guitar's three lowest (E, A, D). The bass and treble sections have separate pickups and are sent to separate amplifiers. Hunter also has a ten-string guitar based on the same principle—a combination of standard six-string guitar and standard four-string bass. The eight-string guitar is used by modern heavy metal guitarists such as Fredrik Thordendal and Mårten Hagström of Meshuggah, Dino Cazares of Fear Factory, Stephen Carpenter of Deftones, Greg Burgess