For starters: the mandolin is generally tuned exactly like a violin. Starting with g3 (the g right below middle c on the piano, aka c4), the next strings are tuned in perfect 5ths ascending giving us altogether g3, d4, a4, e5, or simply g, d, a, e. N.B. The mandolin actually has eight strings, but they are tuned in unison pairs and are played conceptually as if there are only 4 different strings.
Before going further it will be important to read what was said about intervals in this previous post, at least the first four paragraphs. We'll be referring to the chart found there enough that I'll put it up here again:
So, again, for the mandolin (or really any stringed, fretted instrument born of music that has 12 pitches in an octave) we can easily ascertain the name of any interval on a single string simply by looking at the number of frets spanned and finding that number in the chart above in the left hand column. The number to its immediate right will be the name of the interval.
Some simple examples: what is the interval from an open string to the 5th fret? We probably won't need the calculator for this one: 5 - 0 = 5. Consulting the chart gives us P4, the perfect fourth. How about the interval from the 4th to 8th fret? 8 -4 = 4, and the chart says that that is a M3 (major third).
OK, so now when we branch out from one string to another we'll apply this same principle, i.e. we'll simply calculate the number of frets away the two notes in question are and consult the chart. To begin with let's recall that the mandolin is tuned in perfect fifths. How many frets is that? If we locate P5 in the above chart we'll notice it's equivalent to 7 frets. So going from one open string up to the next one on the mandolin is the same as going up 7 frets on the initial open string. Generalized this means that if we have notes on the same fret but on adjacent strings they are a P5 apart, such as:
So now let's look at this interval:
To determine the interval name we proceed in the same manner as before. We've gone across one string (= 7 frets) and up 2 more frets, giving us a total of (7 +2 =) 9 frets. On our chart we see that this is a M6 (major sixth).
How about this one?
Here we've gone across one string and back 4 frets. When we move backwards (lower on the neck) we simply subtract (or add negative numbers, if you like). So we have 7 - 4 = 3, a m3 (minor third) on the chart.
Let's now work the other way around: we'll select an interval and then figure out how it should look on the fretboard. And what better interval to select than the octave (P8)? That's a total of 12 frets according to the chart above. We could do that on the mandolin on 2 strings (or even on a single string) because the frets aren't all that large. but why don't we do it on three strings? Travelling laterally across 2 strings is the same as (7 + 7 =) 14 frets. That's 2 more frets than we need, so all we have to do is go down 2 frets and we should have our octave:
And that's really all there is to it. One thing worth doing: if you're a guitarist/bassist coming to the mandolin you might set your fingers on the instrument in familiar ways and see what the new intervals are. Mandolinists taking up the guitar/bass could do the same thing. It can take the mind a little while to straighten out all of this information as old patterns end up producing new sounds (it's certainly taking my brain a lot longer than expected!) Doing this will lead us into the next post concerning inversion...
