So, do you calibrate a twelve string guitar or not? It is a common question and a very valid one. With fretted instruments we are always battling the limitations of the equal tempered scale. I’ve discussed in previous posts how intonation and calibration works. Basically, frets are placed at a place where a mathematical compromise has been agreed upon. The note isn’t exactly what it should be, but it is “close enough for Rock and Roll” as some like to say. To add to this mess, the distance from the nut of the guitar to where the scale length of the string ends doesn’t take into consideration the precise diameter, tension and distance from the fingerboard that the string actually is in reality. Therefore, on electric guitars saddles can be moved back and forth to “compensate” for this discrepancy. On an acoustic guitar, the bone that is used for the saddle has a specific pattern that is used on the top in order to intonate the instrument as much as possible. But, what about 12 string guitars?