Transposing instruments

It easy to explain transposing wood wind instruments   but ambiguities  occur  when brass instruments are concerned.

This post attempts  to clarify  brass instruments.

 

Reminders: As  far as  transposing  instrument is concerned, the eye  (l’ oeil)   and  ear (l’oreille)  doesn’t perceive the same thing .

For example  a  trumpet player   reads  then plays  « C »  but audience hears B flat.
The aim of transposing  instruments  is  to keep the same fingering  with different sounding instruments.

For  example with  saxophone.saxotenor

In both cases written notes and fingerings are the same but sounds differently


Range of woodwind instruments is clearly established  in the lower register.

There are few exceptions
-One key added on bari sax that can reach A instead on Bb on other saxophones.

-one missing key on English horn which cannot play the Bb of the oboe.

For any instrument, range in upper register   is subject to variations due to  player ability.

This  simplicity is due to the wood wind instrument sophistication through holes and keys which  allow   to select   partials (or harmonics).

Difficulty  of brass instrument  paradoxically results from their  simple construction

Brass are, historically speaking, a  simple flared  tube  with an  embouchure  which allow the  emission of a  note ,the  fundamental or pedal tone  , and its  partials or  harmonics.Those added sounds are simply, if I may say, selected by the way the performer blows in the tube.

serharm

 

Sound  1 Fundamental or  Pedal sound depends on  the length  of the tube.

A mere sight  of the series  reveals a first group of problems.

1-Lower notes progress by skip up to the seventh sound

2- The following conjunct notes are not necessary diatonic to the first sound.

3-  Some diatonic sound are out of tune in our equal temperament  system.

4-The  series doesn’t provide all chromatic sounds.

Our modern instruments are 

-The association of several  tubes (trumpet, saxhorn) to supply the missing notes or the nearest notes of the equal temperament system.

This is done by mean of valves or slide that  broaden the length of the initial tube

-or by fusion  of two  instruments,  as seen in the french horn (F+Bb) or F-attached tenor trombone . The   switching is made with a key.

Three valves provide seven combinations corresponding to  seven bugles covering a tritone chomatically.

trump

Therefore, a Bb trumpet is made of a (no valve) Bb trumpet, an A trumpet, an Ab trumpet.. and so on up to E (the lowest)

Those seven combinations are similar to the  7 positions of the slide of the trombone.

A crook is  another possibility to lengthen the  tube . We can,for example, turn a Bb trumpet into A trumpet but with many defects.

A fourth  valve  extends the tritone range to an octave (12 combinations) which ease the reach of pedal tones especially on  saxhorns.

trp

However, the fourth valve doesn’t necessary mean a larger range. It may only  provide a better intonation but  also bring new problems which possibly require more valves to solve the problem.

A second group of  problems is due to the impossibility to cover the overall series with a single  instrument.

Only instrument with large diameter can reach pedal tones.

Overcoming the harmonics 7  require a small diameter instrument

The  Ratio diameter/length of the  tube is also  important to reach the pedal tones.

The shape of embouchure  is  another factor to select partials which determine the timbre. It may help to reach some  pedal tone but too weak in strength to be efficient.

For instance a bass saxhorn (tuba  ) can reach the contrabass ‘ lower notes  but they are weaker, so the  larger range of the bass   is at the expense of the strength of lower notes.

saxhornbasse

However this instrument is only effective in the following rangesaxhorane

It must not be confounded with the Bb low  bass Tuba which uses a French horn embouchure. Its range is

bastfsounding a second below.

That’s why  we can hardly express the range of brass instruments. Furthermore,instrument makers have evolved lot of devices to enhance the playing which broaden  the range and panel of instruments.

A third  group of  problems   comes under instruments  making and nomenclature.

The first difficulty is

-The name of  instrument which doesn’t reflect  the   register. For example, the  saxhorn Bass  has the range of  contrabass Eb but lower notes haven’t their strength.

-A given  name  correspond to different  instruments   according to countries For  example  » bombardons »   mean   either  contrabass  or include tenor bass. In an other hand the word tuba refer either  to a non-homogeneous group of low brasses  or a specific name for bass-saxhorn  (in C or Bb) or Bb saxhorn  contrabass.

–Confusion of register  and  instrumental group.  Especially    US Baritone (saxhorn) and euphonium  Bb  which is not a saxhorn; its timbre is  different .

The complete  range of   Jupiter euphoniums should stops the confusion.

Another difficulty  is to muddle  tonality of the  original tube  and the concert tone.

For  example, the  trombone is a  Bb  instrument  because  in first   position ( the shortest tube) it  emits a Bb  and its  harmonics but it’s a C instrument  (meaning  non transposing)   because the    trombonist reads and hears Bb  and so does the audience.

Caution:Modern  tubas follow this  logic contrary to former saxhorn- tubas that are transposing instruments.

At least  some  puzzling writing  conventions

-No accidentals on the score for old instruments   (Naturals)

-Treble clef for   « tuben » according to the saxophones logic  to  keep a common fingering for  different (lower Major  sixth (Eb instrument ) or  lower Major  ninth(Bb instrument) Therefore  transposing instruments). This practice is found in the salvation army brass band where all part but bass trombone part are written in treble clef

But the same part may be written in bass key sounding a higher minor third   (Eb instrument ) or  a  lower major second(Bb) instrument

or -written in bass clef with concert tone ( non transposing  instruments).

The problem often occurs with euphonium. The reason is more or less historical  when trumpet players,  only reading  treble clef and playing three valve instrument, switched to euphonium especially with 4 valves.

Fingering of  trumpet Bb  is similar to the one of euphonium sounding a ninth lower.(An Eb euphonium would sound a sixth below)

 

fing-trp-eupjpg

(Figures refer to valves)

Another historical reason is  the octaves determination according to Organ pipes length.

Sound threshold   tallies with a 64 feet pipe

-32 feet pipe corresponds with lower C of a 5 strings double bass

-16 feet  correspond with lower C  of cello

-8  feet correspond  with lower C  of viola

Since Tenor voice was written an octave above its sound,(baritone  saxhorn) is written in treble clef  but sounds as a 16 feet pipe (an octave lower)  On the other hand  a bass  saxhorn  is written (as a bass)  in bass clef ; Being a 16 feet pipe its sound register is similar to the baritone’s one.

Double bass is written  like a bass but as a 32 feet pipe sounds an octave lower .

To summarize

Baritone-Bass____ Different Clef —Same sound

Bass -Double bass—Different sound—-Same  clef

 

« Real » tuba  player  read bass clef and play concert pitch with a specific fingering which is different  according to the tuba tonality). In open, trumpet plays G (treble clef) while tuba plays F'(bass clef). the 1-3 valve combination yields D  to the trumpet but C to the tuba that can  possibly replace the 1-3 by 4

Treble clef writing presents  an ambiguous  zone  due to the large compass  of euphonium

eupdo

 

In the above example , are the framed notes written in concert pitch for a tuba player or in transposed notes written for a trumpet player?

So I advise to use the tenor clef to write those notes in concert pitch.

eupd2

Euphonium is Bb according to the trombone logic explained above and therefore non transposing in bass clef

Nowadays  tuba  scores are generally written in concert pitch (Non transposing)

Since tuba range is very broad, professional tuba players, king of the transposition  choice the best tuba for the given tonality .

tuba-range

For the composer  the difficulty concerns writing for wind orchestra especially  for amateur,unaware of transposition .

From the trumpet range.

trp-range

The three valves  saxhorn baritone is written  an octave lower

F  contrabass  is written a fifth below the baritone and the Eb   contrabass  a sixth  below the baritone  but start on G

Bb bass and contrabass are written an octave below the baritone but start on G with a smaller span (2 octaves).

Tenor trombone shares baritone range while ‘euphonium and bass trombone add a tritone to the lower register

ten-bass

French horn covers the range of the trumpet and of the   baritonecor-range

However the whole range should theoretically  be divided up into low horn  (II-IV)  and high horn (I-III)

 

cor-cor

 

Actually  , the standard writing  is as follow

cortutti

Below is  the advisable range (étendue) of brass instruments (in concert tone)

saxhorhreel

 

 

Avoid pedal tones  in  writing for  trumpet and tenor  trombone . Pedal tone  should be assigned to bass trombone

French horn can emit pedal tones only through the Bb tube but only two pedal tones  (B-A)  are reliable.

When writing for a specific instrument

-it’s advisable to consult the player.

-Whatever the skill of the player one must never forget the general melodic  rules: remain  in the median register with a progressive  reach by step of extreme notes .

More about transposition
Tables of brass instruments (notation and concert pitch equivalence

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