# Understanding transposing instruments

I know just enough about music to be frustrated about how little I know. I was taught to read music and play guitar when I was five or six and I only had time to take one music appreciation class in college. Music feels like this immense and beautiful--but foreign--country that I've been dropped into without a good map and a minimal understanding of the language.

Anyway, I'm trying to figure out a way of hanging onto the explanation for woodwinds having their music transposed, because I'll read the reason and then forget it because I don't have a deeper understanding to relate the concept to.

However, I think I have one, and I'm wondering if this is the right way of looking at it.

On a guitar each string is tuned to a different note, therefore, the note on the first fret is different for each string (save the duplicate Es).

So if I look at, say, the different types of oboes and relate them to the different strings on a guitar, and the keys on the oboe to the frets on the guitar, it seems like I'm looking at analogous situations.

If I understand woodwinds correctly, if you don't press any of the keys, then blowing through the mouthpiece produces a specific note, which could be compared to the unfretted note of a guitar string.

Pressing individual keys on the instrument changes the note, similar to the way that fretting a string changes the note the string sounds.

If that's the rough picture, then you could 'transpose' the notes on a guitar string by, say, indicating A# on the A string as F, B as F#, C as G, etc., if you took the notes on the E string as a rule. You wouldn't because it wouldn't serve any purpose, but you could.

Or, from another standpoint, the notes on transposed music for a woodwind correspond, in a way, to tab notation for a guitar, in that the note written is essentially an instruction for which key to press, in the same way that the number on the tab staff tells you which fret to finger.

A looser analogy might be using a capo on a guitar. If you're going to use a capo, then the chords that you play need to be changed because the open-fretted notes have changed.

Is this roughly correct? And if so, how can I refine this picture?

• guitars are transposing instruments Commented Apr 29 at 16:41
• @NeilMeyer Well yes, but not in the way the OP meant, and they're confused enough that if you're going to introduce further confusing details it seems only ethical to explain better. Rich, Neil means that when using staff notation, guitar is usually notated one octave above its sounding pitch. Commented Apr 29 at 16:57
• @NeilMeyer - What's been confusing me is the reason why transposing less than an octave would make it easier to play a woodwind. I think I've got a better grasp on it now. Commented Apr 29 at 19:20
• @AndyBonner, It seems that transposing by less than an octave serves a different purpose than transposing by a whole octave... Transposing by an octave makes the music easier to read, while transposing by part of an octave makes the music easier to play (although that's probably too much of an oversimplification). Commented Apr 29 at 19:24

For winds, the range of an instrument depends on its length. (Same for strings for that matter.) Manufacturers of instruments liked to make a family of instruments with the same proportions but a different length. For clarinets, we have a Bb clarinet as the most common. For historical reasons, the lowest (or at least easiest-fingered) note is written as a "C" on the score but sounds like a Bb. On an A clarinet, the same fingering (seen by the clarinet player as "C") is a concert A. The same holds for the Eb clarinet. There is an entire family of instruments that have the same fingering (with the same notation) that sound different. The composer has to take this into account in notation.

There are other conventions; some instruments are notated an octave above or below their sound; some like horns need to be checked on Wiki.

The same feature is present in strings, but for the violin family, the names of the notes change. A viola's is tuned (I think) to C-G-D-A as compared to the violin's G-D-A-E. The convention for the violin family (and bass that belongs to another family of instruments, tuned in fourths) is to show the actual concert pitch. The convention with winds is, in effect, to show fingering.

The guitar family could have something similar; I think the convention is to notate a guitar an octave above its sound. The point is to have few leger lines or not too many clefs. Were a guitar to be tuned a half-step up, it would be an "F-Guitar" and have the same relation to a normal guitar as a A clarinet has to a Bb clarinet.

• “The convention for the violin family […] is to show the actual concert pitch. The convention with winds is, in effect, to show fingering.” — Do you know why the different families have different conventions? Commented Apr 29 at 19:19
• @gidds One guess -- and this is just based on my experience as a guitar player -- is that the same note can often be played in multiple locations on stringed instruments. Commented Apr 29 at 19:30
• I suspect it's more fundamental than that, though…  For example, when I learned alto recorder, I didn't treat it as just the descant shifted down a fifth; I relearned the note positions from scratch (which I gather is the usual way).  So I can play it straight from (untransposed) sheet music.  But AIUI most wind players can't; they need music transposed for their specific instrument.  — If it were the other way around, I'd assume it was because the recorder's not generally seen as a professional instrument in the way that, say, the clarinet is.  But this way round makes no sense to me! Commented Apr 29 at 19:54
• A guitar tuned up a half step would not be an “F guitar”. It would be a Db guitar since when you play a C it would sound as a Db, that is provided you want to use the terminology used by brass and woodwind instruments. Commented Apr 30 at 5:58
• contra bass is also a transposing instrument. It sounds an octave lower than notated Commented Apr 30 at 17:50

It's common to be confused about transposition when you're used to instruments tuned in concert pitch (as already noted, guitars are transposing instruments, but since the transposition is of an octave, the problem isn't really perceived).

One way to understand this would be to consider your tuning as the "reference".

Imagine you know how to play a song, that begins with E, F♯, G♯.

Out of your knowledge, somebody tunes all the strings of your guitar half a tone lower: the E strings will actually sound as E♭ (or D♯), A will become A♭ (or G♯) etc.

You come back to your guitar, without knowing about the change in tuning, and start playing your song as you're used (same fingering, etc.).

Unless you have perfect pitch, you won't hear any difference, the song will probably sound fine for you.

You will still be playing E, F♯, G♯ on that guitar, at least to your knowledge.

In reality, you will be playing E♭, F and G, meaning that you're playing a "transposing instrument".
Specifically, you'd be playing in B, which means that what you "read" as C, actually sounds as B.

Your understanding is partially correct, but the example of capo is incomplete, because that device isn't only used for transposing: the point is not only that the open strings are changed, the fingering must move up as well, which is fundamentally the same as the example above: the position of fingers on frets remains the same relative to the open string, the base tuning of the strings changes.

The transposition in wind instruments comes from the fact that most of them have similar fingering in relation to the "open note" (typically, the lowest), which is, by convention, C.

Consider that the music played when these instruments evolved was normally written on a specific key for the whole duration of the piece, occasionally modulating to closely related keys (normally a fourth or fifth above/below).

The parts for those instruments would then always be written in C, and the players would then use the related instrument: the benefit is that the player always reads (and "play") in C, they only need to use a different instrument depending on the actual key of the piece.

This is quite common for trumpet parts of early symphonies, since those instruments often had technical limitations: consider that the first valve trumpets were introduced in 1800, and before that there were serious limits to what they could play. That's why most of the times trumpets only play tonic and dominant in music of that period, and while it was technically possible to play more notes, it was rare to find skilled musicians that were able to do so.

The solution of transposition then is quite ideal: always write in C, so that the player instinctively knows the intervals (eg: tonic, dominant), then just use a different instrument depending on the key. If the symphony is in D, pick up the D trumpet.
This also happened for timpani (which, coincidentally, often play along with the trumpets), that are normally tuned to the tonic and dominant, with the score simply using C and G, and indicating the actual key of the piece. Modern editions are normally written in concert pitch, but it's not uncommon to find some old editions using transposition.

Consider this example from the Mozart symphony n.39 (KV 543), which is in E♭, so the timpani will be tuned in B♭ and E♭, but will be written in G and C for simplicity:

The above is also one of the main reasons for which there are so many transposition instruments in each wind family, even if they are less common nowadays, and professional players normally learn how to transpose while keeping the same instrument.

• "the example of capo is incomplete" If it works as an analogy, I think it only works for chords. You can, for example, play "Free Fallin'" by Tom Petty on the zero fret, using primarily F & C chords, or you can play it with a capo on the third fret using D & A 'shape' chords which are, because of the capo, F & C. The analogy is, I think, between the notes on the music for the transposing instrument and the 'shape' of the chord played by the guitarist. Commented Apr 29 at 19:12

It's not as complicated as it appears, and you've got the initial idea.

If the question is "Why have transposing instruments at all," then if you want an experiential understanding that you'll remember longer, buy a few penny whistles in different keys. You have only 6 holes to work with. You can play a major (or natural minor) scale easily. If you have a C whistle, you can play a C major or A minor scale, and easily play tunes that use the notes of those scales. You might learn a certain tune so well that your fingers are very familiar with the patterns.

Now, you try to play with another instrument, or with a singer. "Oh, I know that tune in A major," they say, or it fits their voice better. A major has three sharps; your standard fingerings for your C whistle has none. Now, you can play sharps by half-covering holes, but first of all the sound of a half-covered hole is different, less clear. And secondly, it's a bit more challenging to do quickly. And thirdly, you already know this tune with your familiar pattern of fingering. At this point, YOU COULD simply play the tune in A major on your C whistle, but it would take some practice and be harder. It would be quicker—and you'd have a different, clearer sound—to simply use a different whistle in which the standard fingering gives you A major.

Now, I picked penny whistle because it's cheap and quick to learn, so you can actually do this. It's capable of playing accidentals with those half-holes, though. For a more dramatic situation, think of the history of trumpets and horns. Before valves, they could only play the notes of the overtone series. A bit of fancy lip-work can let you bend out a few extras, but mostly only in the high ranges. In the low ranges, you are truly limited to only a handful of notes (not even all the notes of your scale, in the low range!).

Now, after the question "why are some instruments 'in' a certain key," comes the question "ok then, why are some instruments today only (or usually) in a certain key, and why that one? Like, why are French horns always in F? Why not C?" And the answer to that question, usually, is just "history and tradition." These natural horns and trumpets were in F as far back as the renaissance. And they usually played all by themselves and not in an ensemble with any woodwinds or strings; it wasn't until Haydn brought them in from the hunt and stuck them in a symphony, and when he did so, he had to write in F. The association with F was so established that, even without using brass, you could suggest themes of majesty and royalty in the baroque just by writing in F. And "the way we've always done things" is so powerful that today, even with valves to let them play all the keys, the symphonic French horn, descended from hunting horns, is still notated in F (and has F as its "default" fundamental).

That's the important part of the answer that you're looking for. There are other points to make about extra parts of your question, but I'll edit to address them later.

• I think your paragraph on valveless horns is the key (pun intended) to understanding "why". It's not just a matter of the easiest note to play (as in woodwinds) but the only available scale. Commented Apr 30 at 14:44
• "it wasn't until Haydn brought them in from the hunt and stuck them in a symphony, and when he did so, he had to write in F" -- See this is the kind of stuff that I wish I had more time to explore. I majored in Art History, and would love to have that depth of knowledge in music as well. Commented May 1 at 18:43
• I suppose I could start by reading the MuApp textbook that I kept... Commented May 1 at 18:44
• @RichJensen Sure! I find it helpful to bring a bit of art into music history and vice versa, and get a snapshot of a whole culture. The renaissance rise of perspective is a common metaphor for the shift from monophony to polyphony, "adding a dimension." Impressionist music is sort of "tonally blurry," like Monet's brushwork. It's easy to create false causation in things that were in fact just correlation (neither perspective nor polyphony were born out of some evolutionary desire to "add a dimension"), but both music and art often reflect the same aesthetics and underlying philosophies. Commented May 1 at 21:05