Transposing Instruments - Am I getting this right?

[nolan]

Hello,

I'm taking an orchestration class and am trying to figure out transposing instruments. Piano is my main instrument, so I haven't really had exposure to the topic before.

In comparison with instruments in C,
- Instruments in Bb sound a M2 lower than written.
- Instruments in Eb sound a M6 lower than written.
- Instruments in F sound a P5 lower than written.

So transposed parts must be written a M2 higher for Bb instruments, a M6 higher for Eb instruments, and a P5 higher for F instruments, in order to sound at concert pitch.

To find concert pitch from transposed parts, move a M2 down for Bb instruments, move a M6 down for Eb instruments, and move a P5 down for F instruments.

Am I understanding this correctly?

[quantum]

That sounds right. 

So when you play a C scale on Bb clarinet, it will sound in concert Bb. 
When you play a G scale on an Alto Sax it will sound in concert Bb. 

[Petter]

Pardon my ignorance but what is the reason why instruments are transposed? Except historical? I´m thinking they sound better if they´re built a certain way too, right? But still you could learn the notes name as they sound in concert pitch. Or would it be too confusing when playing instruments in the same families that resonate higher or lower?

[quantum]

Learning the pitches as concert pitch would be a lot harder.  It would be like turning the transposition function -2, then playing in the key of F# minor on the piano, then think of it as in E minor because that's how it sounds. 

I think it makes a lot more sense when you play one of these transposing instruments.  The piano is very visual, and one can see chromatic key relationships quite easily.  But on some of these instruments sharp/flat notes can be very far in hand position from the diatonic scale which is usually straight forward.  Also the technology wasn't around back then to develop complex instrument keys, so some instruments didn't even possess the full chromatic octave. 

Your reasoning that they may sound better in a certain key is also applicable.

[richard black]

Which direction, up or down, an instrument transposes depends on the instrument. For example:

B-flat clarinet transposes down 1 tone (i.e. sounds 1 tone lower than written)

E-flat French horn transposes down a major 6th

But E-flat clarinet transposes up a minor 3rd

Double bass is written in C (usually!) but tranposes down an octave

and so on.

The reasons for this, in all cases except whole-octave transposition (which is just to make notation simpler), is to do with standardising fingerings and, in the case of brass instruments, making playing possible without valves. The note printed as C on for a clarinet plays with the same fingering whether it's an A, B-flat or high E-flat instrument.

Why they didn't make the viola an 'F violin' I'll never know.