Three courses, six strings, and two intervals that matter
A tar carries six strings in three double courses, and the useful way to hold the tuning in your head is not as six notes but as two intervals. The brass course sits a perfect fourth below the melody course. The bass course sits an octave below the melody — and it is an octave pair, not a unison, so its two strings are deliberately a long way apart. Get those two relationships exact and the instrument is in tune with itself, which is what a tar is actually asked to be.
The letter names below are a written convention. Persian music does not hang the tar on a fork the way an orchestra hangs a violin on an oboe: players tune to the instrument in their hands, to the singer, and to the dastgah, and tuning a whole tone or more below the written pitch is completely ordinary. If the C set feels tight on your instrument, take the whole thing down and keep the intervals.
Two levels of the same tuning. The intervals are identical; only the pitch differs. Damp one string of a course while you tune the other.
The frets move, and that is the real subject
Everything above takes five minutes. The part that decides whether the instrument plays a dastgah correctly is the neck: a tar has twenty-five to twenty-eight frets made of tied gut, and they are not fixed. You can slide them. You are supposed to slide them. On a guitar the intervals are a property of the instrument, decided at the factory and unchangeable without a fret saw; on a tar the intervals are a setting, and a tar set up for one repertoire is genuinely in the wrong place for another.
This is why a tar can be perfectly in tune on its open courses and still sound wrong. The dial can only see the open strings, and the open strings are not where the problem is.
The intervals it needs are not the ones a fixed fret would give you. Persian practice uses a neutral second of roughly 125–145 cents — wider than a semitone, narrower than a whole tone, and available on no keyboard — and a plus tone wider than a whole tone again. Those two intervals are what the movable frets exist to place. See how these tuning systems work for where the numbers come from and how much they vary.
| Interval | Cents | From the nut | Why there |
|---|---|---|---|
| Semitone | 90¢ | 33.4 mm | The Pythagorean limma, 256/243. The one step Persian and Western practice broadly agree on. |
| Neutral second | 135¢ | 49.5 mm | Farhat gives this as a band, roughly 125–145¢, not a value — this is the middle of it. |
| Whole tone | 204¢ | 73.4 mm | The Pythagorean 9/8. |
| Plus tone | 270¢ | 95.3 mm | Wider than a whole tone, narrower than a minor third. The step of Chahargah and Homayoun. |
| Minor third | 294¢ | 103.1 mm | 32/27, the Pythagorean minor third. |
| Fourth | 498¢ | 165.0 mm | 4/3. This one is a landmark: it should agree with your brass course. |
| Fifth | 702¢ | 220.0 mm | 3/2. |
| Octave | 1200¢ | 330.0 mm | Exactly half the string, whatever else you have done. |
Tuning routine
- Set the level before anything else. Bring the melody course up until the tension feels right on your instrument, and read what it says. That note is now your reference, whether or not it is a C.
- Melody course, one string at a time. Damp the second string of the pair with a fingertip while you tune the first, then swap. Never try to read a pair as a unit.
- Brass course to a fourth below. Both strings, unison, damping as above. If the melody is at C4 this is G3.
- Bass course: thick string an octave below the melody, thin string in unison with the melody. Expect the tuner to name two different octaves here.
- Go round again. A tar has a skin belly and a light bridge that stands on it. Bringing six strings up to tension moves the belly, and the courses you tuned first will have dropped.
- Only now check the frets — fourth first, then the neutral second of whatever dastgah you are about to play.
The skin belly, and why the tar moved overnight
The tar’s soundboard is a stretched lambskin membrane, not a wooden plate, and the bridge stands directly on it. Skin is far more responsive to humidity than spruce: a damp room slackens it and the bridge sinks, a dry one tightens it and the bridge rises, and either way the string length and the belly tension change together. The result is an instrument whose whole pitch level drifts with the weather rather than one string going off. If every course has moved by a similar amount in the same direction, that is what happened, and the fix is to retune the whole thing to wherever it now wants to sit rather than fighting it back to yesterday’s pitch.
Frequently asked questions
What notes is a tar tuned to?
Written on C, the three courses are C4+C4 for the melody course, G3+G3 for the brass course a fourth below it, and C3+C4 for the bass course, which is an octave pair rather than a unison. Those two intervals — a fourth and an octave — are the tuning. The letter names are a written convention: Persian players tune the instrument to itself and to the dastgah, and many tune the whole set a tone or more below written pitch to suit the instrument and the singer. Keep the fourth and the octave exact and move the level to wherever the tar sounds best.
Why does my tuner keep jumping between two readings on one course?
Because both strings of that course are sounding. The courses are doubled and they are close enough together that the plectrum sets the neighbour ringing whether you meant it to or not, so the dial is hearing two pitches a few cents apart and cannot choose between them. Damp one string with a fingertip, tune the other, then swap. On the bass course the two strings are an octave apart rather than a unison, so the reading will jump by an octave instead of hunting — that one is easy to spot once you know to expect it.
My open strings are perfect but the dastgah sounds wrong. What now?
The frets. A tar’s frets are lengths of gut tied round the neck, and they are meant to be moved — the intervals a dastgah needs are not the intervals a guitar fret gives, and a tar that has been sitting in a case or set up by someone playing a different repertoire will be in the wrong place for what you are doing. Fret a note, watch the cents readout, and slide the gut until it reads what you want. The table on this page gives starting positions in millimetres for a stated scale length.
Is a Persian tar the same as an Azerbaijani tar?
No, and they are not tuned the same way. The Azerbaijani tar has more strings — usually eleven, including sympathetic strings the Persian instrument does not have — is held against the chest rather than on the thigh, and carries its own tuning conventions. Everything on this page is about the Persian tar. If your instrument has strings you are not plucking, you have the Azerbaijani one.
Can this tuner handle the quarter tones?
It can measure them; it will not name them. The dial names the nearest of twelve notes and tells you how many cents you are from it, which is exactly what you need when you are placing a fret — a Persian neutral second is around 135 cents, so the dial will call it a semitone and report roughly +45, and that number is the thing to watch. What it cannot do is judge you against a Persian scale, because a chromatic dial has twelve notes an octave and the dastgah system does not work that way. The tuning-systems page explains what the difference actually is.