This could lead to confusion!

Here's a site that should explain this reasonably.
http://library.thinkquest.org/16020/data/eng/text/education/theory/ensemb.html

Written and sounding are two different puppies. Remember, the guitar is written 1 octave higher than it sounds. The open A (5th string) is the actual concert 440. Guitar is considered a C instrument. Like a piano, flute, fiddle, etc.

Brass, horns, saxes, harmonicas and certain winds are tuned. It's the nature of the building of the instrument.
Length of pipe, valves, reeds and such. Most people can't afford differently tuned instruments, so a standard arose.
Bb, Eb and F instruments are where they are. Their world is only Bb, Eb or F. They themselves transpose or are transposed (written) to C instruments or concert pitch.

Depending on instrument range the standard is this:
Bb = write a M2 above concert (the key of the tune)
Eb = write a M6 above concert
F = write a Perfect 5th above concert.
Trombones are written in C (or concert standard) in traditional music. (classical) But in brass bands, marching bands and some jazz bands, bones are written as a Bb instrument.
I hope this makes this clearer. This can be horribly confusing. If you have cakewalk, this idea can be heard in midi format.

Oops! I did make a mistake. Griphon is right when it's a Bb instrument like a Bb CLarinet it is written a Major Second Above concert pitch. So if you have a guitar part in G major, you would transpose the Bb clarinet to A major not F major.

:mad: Curse those for making this more difficult.

Ahh, I have the answer to the horrible sounding trombone...
Excellent.

AAAHHHHHHHHHHH!!!!

What nobody has mentioned here yet is that actually horns (and I think possibly saxs) don't even quite play the same scales we guitarists do which, (if I'm right that saxs have the same problem) is why you guys don't sound good together. The natural differences in notes can be corrected only by the lip adjustments or bending/tremolo arm useage of very skilled players. I read somewhere that horn-players who can play in the more widely used scale system are more employable for ensembles etc..

You see the problem is that us guitarists use a tuning system called the "even tempered system" in which the every semitone change involves an equal change in note value (one note is X fraction higher pitched than the previous). This tuning system was favoured by Bach because it allows players to change between keys in a way that only changes one note at a time. A common alternative was that which is naturally easiest to produce when playing a Horn, a so called "harmonic sequence". Here the intervals in pitch are not equally spaced. This produces notes that sit together more comfortably together but it leaves a real problem for modulating between keys.

If you don't believe me read "In Measured Tones" by Ian Johnston, it's a fascinating book. At the time of writing ABE books have three copies of it so here's their URL: http://abe.com

We’re not talking about scales though. We’re talking about the difference in transposition of one instrument to another. A scale is just a group of notes that adds up to a tonality. Like a major scale has a certain sound to it, and a minor scale has a different sound. Even C major and A minor have a different sound (tonality) from each other, even though they have the same notes.

Still concert A (440 vibrations per second) on the guitar transposed to a horn instrument should be the same sound in pitch. Regardless of the system of notes it contains, or distance between each pitch. If it didn’t, all music would sound horrible cause everything would be terribly out of tune. And these distances aren’t too much of a factor because no instrument plays an A note that vibrates at exactly 440 vibrations per second. Even the way you pluck a string on your guitar cause the A note to waver around 440 vbs. You can notice this on a tuner cause it will usually waver ever so slightly, depend on its accuracy. Luckily no human ear is perceivable enough to noticing this difference. Every pitch that sounds in the vicinity of 440 vbs. would sound like an A, regardless of instrument. If it strays to low and sort of in between A and Ab than a cultured ear would notice it being a mix between the sound of A and Ab. Although that is out of tune, and it wouldn't sound good with anything. I think the difference in key between instruments (Bb clarinet) already makes up for this difference in the distance between notes.

I believe you man, but it's not a difference to where it would cause both instruments playing an A to sound that bad. More than likely it was a Tenor Trombone, or an Alto Trombone. Which there was a confusion between notes, but regular trombones are still in Concert Pitch.

OK, just horns that are odd then. I sit corrected.

Fiddles have the same problem. Even college students have an incredibly poor sense of pitch. It's that nature of the animal. An excellent embouchure will make a tone more precise, but it takes time. Trumpets, bones, and french horns have to blow 30 miles of tubing, all in essence by ear. Put your finger on a fiddle at the wrong spot, it's horrendous. Have 27 people do that at once. It's astounding to me horn or brass players exist. They have great personalities, but are gluttons for punishment. A sax made me nearly hyperventilate. This stuff is difficult. I'll just play guitar and piss piano players off. It's more fun.

Yeah any string instrument is the same way. They have to produce the pitch from scratch, not like a guitar where you just hold down on a fret and pluck a string. You have to have an amazing sense of pitch to play strings. That's why most string teachers won't teach students if they're too old, cause the younger you are the easier it is for your ear to be trained.

All true but such difficulty can prevent the instrumentalist
from engaging with another kind of difficulty. So ok it's easy for a pianist to make a note but because it's so easy they're expected to do tons of them, often in counterpoint.
I think guitar's brilliant because we're somewhere between the keyboard (maximimum availabillity of notes) and the violin (maximum abillity to express notes) so not only can we play chordal accompaniments we can also make expressive lead melodies.