All about transposition and the guitar family

What is a transposing instrument?

It's an instrument for which the pitch of the sounded note is different from the pitch of the notated note.
Common examples are the clarinet (which sounds Bb or A when C is fingered) and trumpet (Bb).
In fact, the classical guitar is a transposing instrument because the sounded note is an octave below the notated note.
Other examples include the descant recorder (which is an octave above notation), which explains why it can apparently play lower than the (non-transposing treble recorder) - it can't!
The piano (possibly the most familiar instrument) isn't a transposing instrument.

Are there other examples?

Yes - a guitar with a capo on is most definitely a transposing instrument!
The notation stays the same, but as the capo is moved, the sounded note changes a semi-tone per fret.

What about the guitar family members?

Yes - these are definitely transposing instruments - we'll come back to that in a moment.

What advantages come with being a transposing instrument?

Are all families of instruments transposing instruments?

No.
The brass band is - when C is played, out comes either Bb or Eb, depending on the instrument.
The string quartet isn't - the instruments have different clefs and pitches of strings, but notated C is sounded C.
The recorder consort isn't - the same finger patterns correspond to different printed notes.
The guitar orchestra is. And this is our big payoff - if you can play guitar from notation, you can play any of them - there's nothing to learn.

The Open String E

What transpositions do the guitars undergo?

Here, we get lazy. By rights, we should classify the guitars by what note comes out when C is read. Only then can we compare guitars to other instruments. However, C on most instruments corresponds to "no fingers" or "all fingers", and guitarists tend to classify the guitars by what note comes out when their "no fingers" note - the open top string (always written in the top space of the treble clef) is played.

Instrument Compared to guitar Compared to piano
Soprano, octave, piccolo (E) An octave up At pitch
Alto, quint (B) A fifth up A fourth down
Treble, requinto, quart (A) A fourth up A fifth down
Terz (G) A minor third up A major 6th down
Prime (at pitch) An octave down
Bass, quart bass (B) A fourth down An octave + fourth down
Baritone, quint bass, guitarron in A A fifth down An octave + fifth down
Contra, octave bass, guitarron in E An octave down 2 octaves down

As a short-hand we tend to say the Alto is in B and the Requinto is in A, because that's the pitch of their top string.
In terms that other instrumentalists understand, we ought to say that the Alto is in G and the Requinto is in F, because that's what comes out when they play a notated C.

As you can see, the alto plays "one key sharper" than the prime and the requinto plays "one key flatter". To correct for this, the alto score is "one key flatter" than the prime, and the requinto is "one key sharper".

So is transposition "invisible"?

Just about, yes. Playing a transposing guitar is different to a classical in only three respects :

So can guitar family members play together?

Yes and no!

This gives rise to two corollaries ...

The mental gymnastics of transposition are carried out once - when the music is arranged. Once the guitars are tuned, we can forget all about it and simply enjoy the amazing sounds!

By the way, you can find some humorous musical definitions, including "perfect pitch" on our Musical Director's Website, in the Coffee Lounge

See and hear a small piece of hago score