Pairing of four french horns

I read somewhere on this site there is a certain way french horns are grouped on a score. I think it was that 1 and 3 are on one staff, and 2 and 4 are on another, with 1 and 2 being high horns and 3 and 4 being low? Is this correct?

Yes, in orchestras you will pair French Horns 1 & 3 in one staff and Horns 2 & 4 in another. It's no longer "necessary" to do this, just so common that it's never really changed.

The reason this used to be the case was because Horns used to be built to play in only one key. So, you would have first and third horns playing one horn for a particular key with seconds and fourths playing different horns built to play in another key. Of course, these instruments are built today to play in virtually any key with relative ease.

So, it's one of those historically traditional things that professional orchestras are so used to from playing classical works, conductors just expect to see it organized this way today. We could always try to fight the good fight of progress and change this by writing horn parts differently, but some battles just aren't worth fighting, ya know?

Yes, except horns 1 and 3 are the high, 2 and 4 are low. Thus the order is 1, 3, 2, 4. It makes sense to us horn players and it's what we're used to, especially in orchestra (a lot of composers ceased doing this in wind band).

Simple example - if I spelled a concert F major seventh chord in closed root position, it would be

1st horn: E

2nd horn: A

3rd horn: C

4th horn: F

You'll notice since horns 1 and 2 will be on the same staff, they will spell a perfect fifth, and horns 3 and 4 together also spell a fifth. Quite convenient and easy to read.

Horns are divided into "high" and "low" pairs. These pairs come from historical reasons. In the classical orchestra used one pair of horns with both playing in a particular key. Horn 1 was high, Horn 2 was low. Some time later, another pair of horns were added. Usually, these new horns were in a different key than the first pair and also had a high and low horn. As the instrument developed into a chromatic instrument, the keys became irrelevant and thus the Horn in F became standard. The two pairs, however, kept the old system of being high and low. Thus, Horns 1 and 3 became the "high" horns while Horns 2 and 4 became the "low" horns. Because of this oddity there are two ways to write the score.

1) Horns 1, 2 on one staff, Horns 3, 4 on another.

2) Horns 1, 3 on one staff, Horns 2, 4 on another.

The first is by far the most common and thus almost always has the parts interlocking. See James's example. The second makes more sense if the 1st and 3rd horns are often playing in unison (likewise for the 2nd and 4th). However, the first should be used if the second method would be harder to read.

1) Horns 1, 2 on one staff, Horns 3, 4 on another.

2) Horns 1, 3 on one staff, Horns 2, 4 on another.

Right, it's a spacing thing right? I wasn't sure if I was remembering it correctly. It's so that when a conductor is looking at a score, it's easier to read if there is usually a space between each note (vertically). So each high horn splits a staff with a low one so that the notes don't clash too much.

Right, it's a spacing thing right? I wasn't sure if I was remembering it correctly. It's so that when a conductor is looking at a score, it's easier to read if there is usually a space between each note (vertically). So each high horn splits a staff with a low one so that the notes don't clash too much.

It actually has nothing to do with "ease of use". It's simply a historical oddity that was never corrected. All other instruments go from high to low in the numbers of instruments except the horns because of the historical pairs. A conductor should be able to read it either way just as easily. In fact, sometimes the interlocking is harder to read than the straight high-low in complex passages.

Depends on the conductor - having played horn a bunch I tend to look at scores and see the historical pairs first. In concert band scores where the composer/arranger put them in numerical order instead I get confused when I see the 3rd horn is lower than the 2nd. Just irks me out of my mental custom.

Right, it's a spacing thing right? I wasn't sure if I was remembering it correctly. It's so that when a conductor is looking at a score, it's easier to read if there is usually a space between each note (vertically). So each high horn splits a staff with a low one so that the notes don't clash too much.

As both James and Tokkemon mentioned, the reason behind this is not that it's easier to read, but historical. That it can make some things easier to read is merely a welcome side effect. It also has the positive effect that when in a passage you only use two horns (which also happens frequently, historically), you'd commonly use the first and second (or third and fourth), so you can leave away an entire staff for that passage and still have the full range of a high and a low horn.

Of course, in contemporary scores it's also very common to put every single instrument on an individual staff, which is particularly useful if the instruments play very different rhythms, possibly cross voices, or have lots of different symbols (dynamics, articulations, etc.) attached to them that aren't the same for all of them. Most of my scores have all woodwinds and brass on one staff per part, unless the score would get too big otherwise and I have to compress things a bit (and the music allows for that, such in the case of some orchestrations).

But if you write them in two staves, I would always put horns 1 and 2 on one staff and horns 3 and 4 on the other. The other variant is close to non-existent and nothing but confusing, IMHO.