I understand that historically there was a need for transposing instruments. e.g. Brass instruments would use lead pipes to change their key and players in brass bands would like to stick to the same fingering when swapping between instruments. However, I'd have thought that all these instruments could be remade to sound just as good as the originals and to have the same fingerings as one another, but written in C (i.e. concert pitch).

It also seems strange that bass clef isn't moved a couple of lines to read the same as treble clef (but two octaves lower), with alto/tenor clefs being removed.

Is the reason purely academic, is it because of the chaos caused during the transition period, or is there some practical reason for this?

  • 1
    Related: music.stackexchange.com/q/5374/1678
    – Luke_0
    Commented Sep 18, 2012 at 14:19
  • ps. regarding the answer for the bass/treble clef being made around middle C, you could keep this and have both clefs read the same by adding another line to the top of the treble stave and the bottom of the bass. Both clefs now read the same and middle c maintains its position.
    – JohnLBevan
    Commented Sep 19, 2012 at 9:03
  • 2
    I would have thought it was about keeping as many notes on the staff as possible, but then I remember when I played the string bass part in a band in high school and all the music I was handed lived 5-6 ledger lines below the staff...
    – Kaji
    Commented Jul 8, 2014 at 22:34
  • Brass instruments had no fingering in those days. (Also, the pipes were brass, not lead.)
    – phoog
    Commented May 21, 2018 at 5:20
  • 1
    Ah, thanks. The pitfalls of homonyms! :-) For years I wondered why journalists would "bury the Pb" until I realized that it's sometimes spelled in jargon as "lede." But still, brass instruments had no fingerings (and for a valved brass instrument you would need to increase the length of the loops of tubing controlled by the valves as well as of the entire instrument). :-)
    – phoog
    Commented Aug 23, 2022 at 11:32

6 Answers 6


The TL;DR answer:

  • Some instrument families (saxophones, clarinets, double reeds) have variants which change the instrument range by something other than an octave. To make it easy to switch between instruments in the same family, the parts for these instruments are transposed so the same written note has the same fingering, but produces a different actual pitch.
  • Even when the range of two possible tunings of an instrument are basically the same, the two tunings are often kept around for instruments like woodwinds where playing in a key too far removed from the instrument's "native key" is difficult. The pieces for these alternate tunings are transposed for the same reason as the previous point (easier to switch).
  • We already have a huge body of work written for transposing instruments, and virtually all musicians playing those instruments are very familiar with reading for those instruments in their transposed keys. Changing all that requires editing every piece of music that's ever existed before being able to put it in front of people trained to read the instrument in concert pitch (or an adjusted simplified transposition), and retraining all existing musicians (or maintaining transposed and concert-pitch versions of all sheet music until all the traditionally-trained musicians retire/die off).

  • The bass clef reads the way it does because of its position in the grand staff; "Middle C" (C4) is exactly one leger line above the bass clef and exactly one leger line below the treble clef. That's why middle C is so named. It makes more sense, given that explanation, to keep it that way than to try to change it. If you like, you can move the bass clef up one line, to indicate that the top line represents F, creating the subbass clef; the staff would read exactly like the treble clef then, but you'd confuse the hell out of most bass-clef readers.

The longer answer:

First, although there has been considerable standardization of instruments, and most orchestral instruments can now play chromatically, many instruments in the modern orchestra are variants of an instrument normally taught to beginners; most clarinetists learn to make their first squeaks on a Bb soprano clarinet, and then candidates are typically culled from that group to play the alto and bass clarinets, with a few occasionally given a piccolo clarinet. Saxophonists are typically steered first to the Eb alto sax, then branch out to the Bb soprano sax and tenor sax, or the Eb bari sax. The oboe (C) naturally leads to the cor anglais (F). The idea with these is, you play the written note with the same or very similar fingering, thus allowing you to more easily switch instruments without completely starting over. For these families of instruments, transposed keys are still very useful for their original purpose.

However, that could still mean that we could have only one or two transposed keys, by picking one instrument of the family and not transposing its part (making that the "C" instrument), and then others would be transposed relative to that instrument (so Bb saxes would become C instruments by simply writing Bb as Bb and not C, and Eb instruments would become F instruments; almost all transposed instruments would then be either C or F).

Another big reason, highly related, is that even though an instrument can play any note does not mean that it is easy to do so. Woodwinds are a big one here; they have a "native key" which is played primarily by simply lifting and pressing one's fingers over the open holes in the body of the instrument. Other keys, usually ones on the opposite side of the instrument's tuning and especially ones more than a few "shifts" away from the native key on the Circle of Fifths, become difficult to play because they start bringing in a disproportionate number of the "banana keys" (or "bar keys" or whatever they look like on the instrument in question), which are typically placed wherever it's possible to put them and for the player to get to them, which is usually not the "logical" place to find a key that opens that pad.

To reduce the use of these more difficult keys, alternate tunings of the instrument are available that have pretty much the same range (unlike the saxophones and the alto/bass variants of the clarinet/flute) but have parts written so that the note with the same fingering gets the same written pitch, but produces a different note thus giving the instrument a different "native key" that allows the player to use the instrument that is closer to its native key when playing in the concert key.

While we could still pick one instrument and call it the "C" instrument, for the clarinet at least, that position is already filled; there are A, Bb and C clarinets in existence (A and Bb are the ones typically seen in American ensembles but the C clarinet is still available). There are also trumpets and cornets with partials tuned to C (but, many low brass instruments are available in both Bb and C partial tunings, and yet those parts are usually in concert pitch, so one could argue that the trumpets and french horns could simply get with the program).

The biggest reason is that music is like history; it is the sum total of everything that has come before. So, if we were, at some point, to say "OK, from now on, we'll teach all new entering middle school band students in concert pitch and do away with all this transposing", we'd have to go back and transpose every piece of music that has ever been written for those instruments. Then, all the existing master instrumentalists would have to re-learn how to sightread for their instrument (something I don't think they'd be keen on, meaning for the next 50 years or so you'd have to keep and differentiate between "concert key" and "transposed key" versions of the part for each transposing instrument and each piece). It would be a painful transition, and we in the U.S. don't tend to like changing basic learned patterns, even if it would ultimately make our lives easier (one of the reasons the U.S. still hasn't fully switched to metric, and most of us still type on QWERTY keyboards, which are difficult to use by design)?

  • "The bass clef reads the way it does because of its position in the grand staff; "Middle C" (C4) is exactly one leger line above the bass clef and exactly one leger line below the treble clef. That's why middle C is so named": this is a popular and enduring myth, but it is a myth. The bass clef was standardized long before the grand staff was.
    – phoog
    Commented May 17, 2021 at 14:07

Technically, there are no reasons, but practically, there are quite a few. Obviously, we've reached the point where we can construct instruments that are fully chromatic, so there is no need to change crooks and play only the overtone series.

The practical reasons are many, and mostly stem from the fact that if all instruments were pitched in C, any time you want to shift up or down to a higher or lower-sounding instrument, you would have to jump an entire octave.

  • Modern classical performance involves playing lots of music written for instruments with traditional transpositions.
  • Artisinal instrument manufacturers have been perfecting the construction of these transposing instruments for generations.
  • Wind instruments do not play like synthesizers. The timbre has different qualities based on what part of the horn you are playing in. So, if you have a C trumpet, a C bass trumpet, and a C piccolo trumpet, and if they ALL have a "cash register" of a few notes around the 5/6th partial, you're going to be missing a LOT of potential tonal real estate until you start constructing new instruments that make serious tradeoffs in order to play a certain way over certain parts of the range while still being pitched in C.

If you want some food for thought, ask yourself the question "Why do we write music in keys other than C?"

The clef question is an easy one, so I'll tack on an answer here. The bass and treble clefs are symmetrical around middle C, which makes perfect sense for piano players reading a grand staff. For everyone else, the many different clefs exist so that instruments or voices that sing or play in a certain range don't have to spend too much time reading ledger lines. Also, a common shorthand to shift a clef by an octave is to notate a small 8 directly above or below it. Tenor vocal parts are often written this way since their notes typically lie above the bass clef, but perfectly within an 8vb treble clef. Conversely, descant recorder parts are occasionally written in 8va treble clef. There are exceptions, of course; instruments such as crotales, piccolo, and double bass sound up or down an octave without an 8va/8vb clef, and are considered transposing instruments as a result, even though they are all pitched in C.

  • You might want to add that the clef is often shifted up an octave by putting an 8 directly above, such as with the descant recorder.
    – Luke_0
    Commented Sep 18, 2012 at 16:10
  • "Why do we write music in keys other than C?": fantastic :) A technical reason: in the case of the trumpet, the low G on a Bb trumpet is occasionally used (not very often, but not too seldom either), and you can't reach it with a C or D trumpet.
    – Gauthier
    Commented Nov 12, 2012 at 13:42
  • While I've never tried to play 7-octave handbell music, I've seen it, and have thought that it would be clearer if there were another staff above the treble staff. 8va notation is fine if one doesn't have notes spread throughout many octaves, but the music I saw had upwards of five ledger lines above the treble cleff--how is one supposed to read that?
    – supercat
    Commented Jan 29, 2013 at 5:09
  • 3
    Excellent answer,don't forget the humble guitar - an octave transposer. I think that lots of guitarists possibly aren't aware that they're playing an octave down to the written part.
    – Tim
    Commented Apr 12, 2013 at 11:25
  • 2
    @Yarin Thats both a bit of a joke and an advanced theory concept. "Cash register" is a pun on the concept that there is a register of the instrument, and proficiency in playing in that register is what professionals use to make their $$$. A 'partial' is a member of the harmonic series inherent in any brass instrument, which exists relative to the key of the instrument.
    – NReilingh
    Commented Aug 13, 2015 at 21:11

There is an overarching reason for transposition of wind instruments, which can be corroborated by anyone who has played woodwind doubles in a pit orchestra.

Regardless of the reason transposing instruments came into practice in the first place, the practice is still standard in writing circles (besides the valid observation that there alr4eady exists a huge body of already-transposed repertoire) is quite simple:

Instruments transpose so that players of a particular instrument, or type of instrument, can play any of an entire family of their weapon of choice using the same fingering scheme.

For instance, modern clarinets come in a huge variety of sizes -- E-flat Sopranino, B-flat Soprano, A Soprano, E-flat Alto, B-flat Bass, E-flat Contra-alto, B-flat Contra-bass ... and even F Basset Horn (which is actually part of the clarinet family and is retained in the orchestral arsenal largely because of the large amount of music Mozart wrote for them). Interestingly, ALL of these clarinets use virtually the exact same fingering scheme, which allows any clarinetist to switch easily among the various varieties -- for an entire work or performance, just one selection, or even in the middle of a single work and back again. In addition, virtually all of the woodwinds are built on almost identical fingering methodologies -- with the exception of Bassoon (although the bottom register of a clarinet highly resembles that instrument's fingering structure). The Saxophone family is similarly varied, and the same fingering principles apply from one to the next. If you look at fingering charts for Flute, Oboe, English Horn, Clarinet and Saxophone, the note "D" is fingered in precisely the same way because the parts for these instruments is transposed to allow for this.

If the instruments were NOT transposed for the players, the same condition would exist as that for the recorder family. Although recorders are constructed almost identically except for their physical size, the fingering schemes for each of these is different -- BECAUSE the practice of transposition has never been applied to them. As such, in order for a Soprano recorded player to switch to Alto recorder, it is necessary for the player to learn and entirely different set of fingerings (and, in many cases, to learn to read a new clef as well).

The brass instruments are similarly described. The fingering patterns for brass instruments are identical between transposing trumpets and horns -- and since there are 7 different possible fingerings for a trumpet or horn which correspond to the 7 different possible positions on a trombone, the resemblance throughout the family is complete.

In modern practice, bass-clef instruments do not transpose ... but, in order for a treble-clef brass player to read music written for Euphonium or Tuba, the player has either to learn an entirely new set of fingerings or transpose the pitches into a different key in their head while playing. So many trumpet players have switched to Euphonium over the years that a B-flat, treble-clef part is nearly always included in wind band literature to allow for this shift.

One final note (pun intended): Many writers and conductors seem unaware of this circumstance, but if one plays the note "C" on any instrument, regardless of its transposition, the instrument will sound the note of the key in which it's built. The only exception to this is low-brass instrumentation -- which, since they don't transpose (see above) have learned a set of fingerings peculiar to their instrument in terms of pitch-level. As such, a tuba play can't play a trumpet or horn without moving the notes in his or her head to allow for this difference.

Finally, bass clef NEEDS to be different that bass clef -- in order for a conductor or keyboard player to be able to maintain the difference between registers while conducting or performing. A pianist or organist would be easily confused when reading down a page if all the notes were on the same lines; the beauty of a grand- or three-line-staff is that a player can keep a reference point because the clefs are vertically grouped and arranged on differing lines and spaces. If this were not the case, players would be much more likely to play wrong notes in wrong registers, particularly when sight-reading.

  • 1
    +1 Nice explanation. Welcome to the site. I removed the signature because all your messages here are already signed with your user card. Commented Jan 29, 2013 at 1:14
  • Your comment re tuba is probably correct for modern orchestral parts and possibly for American wind bands. But the traditional British brass band parts would have tuba in Eb and Bb both reading a transposed treble clef part.
    – kiwiron
    Commented Mar 29, 2015 at 7:07

Wind instruments have their basic mechanisms and ranges designed around a diatonic scale, and notation is also designed around a diatonic scale.

If you tell all piano players "from now on, you'll be playing everything a minor third higher on sight", all except the most skilled ones will not be amused: their keyboard is designed around the diatonic scale of the notation as well.

In contrast, if you tell a chromatic button accordionist, he'll shrug and say "why not?" since his "keyboard" is regularly patterned to the chromatic scale.

Now if you take a look at accordion orchestras even in button-accordion heavy countries, you'll find a disproportionate amount of piano accordions, and part of that reason is that playing an instrument designed around the chromatic scale from a score designed around the diatonic scale requires mental acrobatics, particularly so if we are talking about polyphonic instruments.

Guitar on the amateur level is played a lot from "tablature" where the notation matches the instrument controls again. So there is quite a bit of evidence that people don't really fancy a mismatch between notation and instrument controls, and spontaneous transposition is not really a readily available basic skill.


The short answer, and the one that is most practical for the performer is that the concept of a transposing instrument means that a saxophone player for example, can play all the saxophones in the range. A tenor player does not need to relearn the fingering if he or she switches to alto.

Practicality is certainly the main reason. The most popular instrument of the last 50 years, the guitar, does not sound as it is written: the guitar sounds one octave lower than written. If it wasn't, guitarists would need to read bass and treble clefs like the piano. This would make reading for the guitar very difficult indeed.


I see very long explanations.... here's my short version:

  • Suppose you spend 10 years learning how to play the normal plain flute in C. 10 years reading middle C to be written on the first additional line bellow the pentagram. Nice... then a composer writes a piece of music that requires the flute in G because he needs a bit of a deeper graver sound. And he wants to hear a non-transposed D (first additional space bellow the pentagram on a normal flute). And so he writes a D the same way he has always done. So, the flute player reads that and he sets his fingers to play a D (on the plain old C flute) the way he has done it for the last 10 years and then he blows and what do we get? Instead of getting a D we get a non-transposed A (because the flute he is playing is on G, remember?). The composer could then yells from the seats (cause he is listening to the rehearsals of this piece.. it's a world premiere), Hey!!! That's a D that you have to play!!! But then then flute player will bark from his seat: Dude, write accordingly for the flute I'm playing... I'm not going to relearn how to play a D on my flute just to fit this piece... you better write a G on my part instead so that it will actually produce the sound you want.

And that's the gist of it.

  • 1
    -1 as it doesn't say anything useful that KeithS hadn't already said 5 years ago, and for bad English.
    – Rosie F
    Commented Mar 1, 2018 at 19:36
  • @RosieF there's no need to criticize people's language skills, and there are many reasons for refraining from doing so. Furthermore, the English in this answer is far better than in many highly upvoted posts.
    – phoog
    Commented May 17, 2021 at 14:14

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.