Eight strings, four courses, six pitches
A modern Greek bouzouki is a tetrachordo — four courses of two strings — tuned C3–F3–A3–D4, read from the fourth course to the first. But that is only six of the eight strings accounted for, because two of the courses are not unisons:
- 4th course, C: C3 paired with C4 — an octave apart.
- 3rd course, F: F3 paired with F4 — an octave apart.
- 2nd course, A: two strings at A3, unison.
- 1st course, D: two strings at D4, unison.
Those two octave courses are most of what people mean by the bouzouki sound. A melody played on the top courses rings against octave-doubled lower strings, which is what produces the bright shimmer underneath — and it is also why a course can read perfectly centred on both strings while one of them is in the wrong octave entirely.
The first tab is the standard tetrachordo, with each octave pair split so you can hear both halves. The second is the older trichordo. The third is the Irish tuning, for comparison — only the A and D courses survive the crossing.
Trichordo and tetrachordo
Two instruments share this name in Greece, and the difference is a course and about three decades.
The trichordo is the older one: three courses, tuned D–A–D, and the sound of classic rebetiko. The tetrachordo arrived in the 1950s, adding a fourth course and shifting the tuning to C–F–A–D, which widened the range and made the chord shapes of Western-influenced Greek popular music far easier to reach. It is the standard today; the trichordo is a deliberate choice for older repertoire.
For tuning purposes they are effectively separate instruments, so the first question is always which one is in your hands. Count the courses.
Tuning routine
- Confirm trichordo or tetrachordo, and check the octave digit on each string of the two lower courses before you change anything — that tells you how the instrument is currently strung.
- Start with the 1st course, D4. It is a plain unison and the clearest reading on the instrument.
- Then the 2nd course, A3.Also a unison, and it is concert A’s octave below, so it is easy to sanity-check.
- Now the octave courses, one string at a time. F3 and F4 on the third course; C3 and C4 on the fourth. This is where the octave digit matters most — the two strings of each pair answer to the same letter.
- Finish every course by ear. Unisons must stop beating; octave pairs must lock into one sound rather than two. On steel strings the upper octave often wants to sit a cent or two sharp before the pair really settles.
- Go round again. Eight strings on a lightly built bowl-back body move the instrument as you work, and the first course you tuned will have drifted by the time you finish the last.
Where the Irish instrument came from
In the mid-1960s Johnny Moynihan took a Greek tetrachordo and retuned it from C3–F3–A3–D4 to G2–D3–A3–D4 to suit Irish traditional music. The tuning stuck and an instrument grew around it — flatter backs, longer scales, and, importantly, all-unison courses rather than the octave pairs a Greek instrument carries.
Look at the third tab above and you can see how far the two have travelled: only the A and D courses survive the crossing unchanged. Everything below them moved. Our Irish bouzouki tuner covers that instrument on its own terms.
What the needle can and cannot settle
The dial gets six pitches right, and on a coursed instrument that is only half the work. The other half is the pair, and the pair is where the sound lives.
A pair whose two halves both sit dead centre can still pulse audibly, because the tolerance the needle treats as “in tune” is wider than the difference your ear picks up between two simultaneous notes. The octave courses add their own twist: steel strings carry partials that run marginally sharp of the arithmetic, so an octave set to the numbers can sound very slightly compressed. Let the beating make the final call. Our guide to cents explains why. For related coursed instruments, the mandolin and the oud are both worth a look.
Frequently asked questions
Which courses on a Greek bouzouki are octave pairs?
On a tetrachordo, the two lower courses. The C course is C3 paired with C4, and the F course is F3 paired with F4 — each an octave apart. The A and D courses are plain unisons, two strings at the same pitch. So the instrument has eight strings but only six distinct pitches, and the shimmer people associate with bouzouki sound comes largely from those two octave courses ringing under the melody.
What is the difference between trichordo and tetrachordo?
Three courses against four, and about thirty years of history. The trichordo is the older instrument, with three courses tuned D–A–D, and it is the sound of classic rebetiko. The tetrachordo added a fourth course and was developed in the 1950s, tuned C–F–A–D, which gave players a wider range and easier access to the chords Western-influenced Greek popular music wanted. Today the tetrachordo is standard and the trichordo is a deliberate choice for older repertoire. They are tuned differently enough that they are effectively two instruments sharing a name.
Is this the same instrument as an Irish bouzouki?
It is where the Irish one came from, but they are no longer the same. In the mid-1960s Johnny Moynihan took a Greek tetrachordo and retuned it from C3–F3–A3–D4 to G2–D3–A3–D4 for Irish traditional music. That tuning stuck, and instruments built for it since have diverged — flatter backs, longer scales, and all-unison courses rather than octave pairs. Same ancestry, different tuning, different repertoire, different build. If you have an instrument with a deeply rounded bowl back and octave courses, it is Greek.
A course reads centred on both strings but still sounds wrong. Why?
Check which course it is. On the A and D courses, two strings at the same pitch can both read centred and still beat audibly, because a few cents fits inside the needle’s tolerance and not inside your ear’s — finish those by ear. On the C and F courses the answer is usually different: those are octave pairs, so a string can be in the correct place for the wrong octave. Play the two strings of the course separately and read the octave digit on each before assuming the tuning is fine.
How do I tune a course without the other string interfering?
Damp it with a finger. Two strings sounding at once give a detector a signal it has to average, and on an octave course it gives it two genuinely different pitches to choose between — which is how you end up chasing a reading that does not correspond to either string. Rest a fingertip on the string you are not tuning, set the one you are, then swap. Only once both are individually correct do you play them together, and at that point you are listening rather than looking.