The Ibanez RG350DX is a six-string electric guitar. It has a "Zero Edge" tremolo system. This system is based on the innovative double-locking Floyd Rose system. The double-locking tremolo features a nut lock that puts downforce on the strings, increasing tuning stability, meaning aggressive use of the tremolo arm doesn't cause the guitar to go out of tune. Although the tuning is typically more reliable than on a standard tremolo, humidity can cause the strings to slip out of tune. Rather than unfastening the nut lock to correct minor tuning issues, use the six thumbscrews for minor adjustments.
Fit a 2.5mm hex key into the first of the three nut locks, covering the E and A string, at the top of the fretboard. Turn it clockwise until you hear the strings vibrate. Unlock the remaining two nut locks in the same manner. This relieves the downforce on the strings, meaning the double-locking mechanism is temporarily disabled.
Turn each thumbscrew on the bridge so it sits at the halfway point. This permits equal tuning scope in either direction when the nutlock is fastened.
Connect a 1/4-inch jack cable between guitar and tuner. If the tuner points right, the string is flat. If it points left, the string is sharp. Tune the strings in typical fashion, tightening the tuning machine to correct flat notes and loosening the tuning machine to correct sharp notes.
Fasten the three nut locks with the hex key. The downforce applied to the strings holds them in tune. When the nut lock is fastened, the tuning machines and tremolo cannot influence the tuning of the strings. You can alter the tuning with the thumbscrews only while the nut lock is fastened.
Play the fifth fret on the low E string and the open A string in quick succession. You can locate the fifth fret quickly by using the "shark tooth" inlay as a guide; count three shark teeth from the nut to get to fret 5. The notes should be the same pitch if the guitar is in tune.
Tighten the thumbscrew that sits above the A string saddle If the E string note is higher in pitch. This increases the A string in pitch. If it is lower, loosen the A string thumbscrew. Recheck and make further small adjustments until the two notes are the same pitch. Because it is the thickest string, the E string makes the most reliable tuning reference note when you don't have access to a tuner.
Play the A string at the fifth fret and open D string in quick succession. Adjust the D string thumbscrew so the D string is the same pitch as the fifth-fret A string.
Repeat the process for the remaining four strings, using the fifth fret of one string as a pitch reference for the next-highest string. When you are tuning the G and B strings, use the fourth fret of the G string as the tuning reference.
When changing the strings on an Edge Zero bridge, remove and replace one string at a time. If you remove all the strings together, this can cause the springs holding the tremolo in place to stretch. Resetting the springs is tricky.