The horn is the only component of concert ensembles that is regularly broken down into four equal parts.  Being an F-pitched instrument, the horn enhances the middle brass sonority, which is often flabby and lacks power.  The horn section augments the trumpet's low register by adding greater depth to the tone and projection.  Likewise the upper region of the trombone range is often thin and strident.  The horn's powerful and heroic tone can fatten the tonal color of a band while allowing the trombone tone to become more resonant.

Many directors speak favorably about bands or orchestras with fine horn sections, but they often view it as a color instrument because the horn is not regularly featured.  This is a misconception because the horn has been a prominent solo and section voice in orchestral music for 150 years.  In the early days of band repertoire, composers relegated the horn to playing filler passages in transcriptions.  Today the horn has regained its position as an integral part of the wind ensemble. An adequate horn section is no longer a luxury to a band program; it is a necessity.

A horn that is properly tuned takes less effort to play correctly.  Walter Lawson, horn designer and acoustician, recommends using a chromatic tuner to adjust a double horn.  Begin by moving the main tuning slide until open C on the Bb side is in tune.  Approaching the C with a diatonic slur of a perfect fourth gives a more accurate reading of intonation tendencies.  Next, play the same slur and hold the pitch while smoothly releasing the Bb thumb valve; players should not focus on the change in tone color between sides but on the valve change itself to avoid distorting the intonation.  Adjust the F side tuning slide so both open horns are in tune.

On the F side, tune open C to the first-valve ninth harmonic C because this partial is relatively in tune.  Continue by slurring F to Bb on the F side.  While holding the Bb depress the thumb valve to adjust the intonation of the Bb side first valve to that of the F side.  Then play D5 open on the F side and depress the correct combination on the Bb side while sustaining the pitch.  Adjust the notoriously sharp D5 on the Bb side by pulling the second valve on the Bb side.

To adjust the second valve on the F side of the instrument play a diatonic slur F# to B, sustain the B, and release the trigger.  Cross-check the first and second combination.  As for consistency, a slight discrepancy is acceptable, but if the pitches are noticeably different perform the last step again.  Some instruments have auxiliary Bb tuning slides for fine tuning of this small intonation problem.  Players should adjust this slide to match the intonation of the Bb and F sides.

The last step is to adjust the F side third valve so it is slightly flat to the first and second combination to compensate or the natural out-of-tune tendencies of long valve combinations.  After this is done, adjust the Bb side third valve.  Check this third valve intonation with a diatonic  slur from Eb to Ab on the Bb side.  Hold the top pitch and release the thumb valve to check intonation on the F side.  Performing several scales two octaves while another person monitors a tuner helps to identify some personal intonation tendencies.  Hornists should follow this procedure weekly and make daily adjustments with the main and auxiliary F tuning slides in the interim.

There are other tuning problems that pertain to all members of the valved brass family.  Christopher  Leuba's Treatise and Brass Intonation offers a thorough discussion of brass intonation problems.  Brass players should consider the natural intonation tendencies of the harmonic series.  These intonation properties remain constant when playing the open pipe or any of the possible valve combinations: the third, sixth, and twelfth partials coming off the fundamental are naturally slightly sharp, and the fifth and tenth partials are noticeably flat.

Mechanical intonation tendencies in valved brasses are a problem and mathematical ratios come into play.  While individual valves lower the open tube a prescribed amount, this is not the case with valve combinations.  As a rule,  the longer the valve combination, the more sharp an instrument becomes.  The combinations 12, 23, 13, 123 become progressively more sharp.  These two principles together drastically affect a brass instrument's intonation.  For example, a sharp fingering used on a normally flat partial may make the desired pitch close to being in-tune,  but a long-valve combination on a normally sharp partial will make the pitch excruciatingly sharp.

Directors and brass students alike should understand the natural intonation tendencies of the brass family.  The appalling number of noticeably out-of-tune notes in performance are proof that many teachers neglect this area.  There are various basic rules that brass players should follow to adjust intonation.

Trumpet players should use the first valve saddle and third valve trigger when playing long valve combinations and lower octave fingerings on the flat fifth partials to help fix problematic pitches.  It is important that beginners learn these skills when first studying the valve combinations.

Hornists should gently cup or flatten the right hand or use the jaw to lower and raise the pitch.  If intonation remains a problem after hand adjustment substitute the third valve for the first and second combination.  Using the Bb side of a double horn to play low C# and D avoids the long valve combinations on the F side.  Trombonists should adjust slide positions, use alternate positions to get first position partials in tune, and pull the main tuning slide the correct distance.

Euphonium players should adjust the first, second,  and third tuning slides correctly by using a tuner; these slides should not be pushed all the way in.  Fourth valve can substitute for the one and three valve combination on a regular basis, however, this does not solve the problem of increasingly sharp notes when more valves are added.  Use of compensating three- or four-valve models and adjusting the main tuning slide on problematic notes will also help euphonium players.  Tubists should basically follow the same rules as euphonium players except on rotary valve tubas and some piston valve tubas, players might be able to grasp the first and third extended valve slides to help adjust pitch.

The best rule to follow when tuning large ensembles is to build the pitch center from the bottom of the ensemble.  W. Francis McBeth's Effective Performance of Band Music offers a thorough explanation for this procedure.  Tuning down through the ensemble will not only help intonation but will improve balance and blend.  A round sonority and transparent texture are additional by-products of this procedure.

Begin by dividing the ensemble into five groups:  group one, contra bass clarinet, tuba, and baritone sax; group two, bass clarinet, trombone, bassoon, tenor sax, and euphonium;  group three, horn, alto sax, alto clarinet, and English horn; group four, Bb clarinet, trumpet, and oboe; and group five, flute, Eb clarinet, and piccolo.  Keep a chromatic tuner nearby and occasionally glance at the dial throughout the tuning process to make sure the established group tonal center has not drifted.

Select an arbitrary scale and have group one play the first scale degree.  Players should breathe at will while blending and balancing the pitch.  After group one has accurate pitch have group two enter.  Not only should group two listen to and match the basic pitch, they should always be able to hear the voices of group one throughout the exercise.  Group one should continue to hold the pitch until all the groups have entered.  Repeat the entire procedure on every note of the selected scale so students realize that adjusting intonation is necessary on some pitches; the goal is to develop students' ears for proper intonation and balance in an ensemble.  Directors can check ensemble intonation by performing Bach chorales or working through the Treasury of Scales, using the bass voices on the diatonic scale assignment.

The majority of players switch to horn from different instruments, most often trumpet, flute, and clarinet.  When working with newly recruited hornists, use an adequately large vowel, such as ah or oh, while playing because trumpet, flute, and clarinet use a very small, closed oral cavity.  Have students relax the jaw and blow air as if warming their hands on a cold morning to learn how it should feel to play using a large vowel.

Students should begin by buzzing the mouthpiece alone, using a breathy buzz to generate the tone.  A wind resistance machine to hook the mouthpiece into approximates the brass tube resistance and gives students a visual reference as they move air past the lips.  It takes a large amount of air to generate an adequate horn tone. The F horn has as much tubing as the F-attachment trombone, and although the mouthpiece is considerably smaller and the acoustical tube is more narrow, players of both instruments use the same energy to generate a tone.

There are several machines to help students build air control and lung volume.  The breath builder exercises lungs to provide a consistent flow of wind.  A player may increase resistance by covering vent holes.  The volume meter measures lung capacity and illustrates how effectively a person is using the lung's maximum capacity.  An incentive spirometer improves the ability to inhale larger amounts of air in a given time frame. This machine is equally effective to use while buzzing a mouthpiece to produce a consistent air flow.  These machines are available in music catalogs or from respiratory supply companies.

Hiring guest artists to perform on a student program or taking students on a field trip to hear a collegiate or professional symphonic orchestra raises awareness of how the horn should sound.  There is also an abundance of quality horn recordings available so students can hear professional artists perform on a regular basis.

There is often some confusion about the assignment of parts in a horn section.  Traditionally the first and third chairs are higher pitched horns than the second and fourth chairs.  This setup come from the orchestral practice of using pairs of natural horns in complimentary keys.  At certain times, as evidenced in the orchestral music of Brahms, the second pair of horns is at a higher pitch level than the initial pair.

The principal hornist should have a well-developed, controlled tone in audition to advanced technical facility.  This is the solo voice of the section, so a suitable student should have enough maturity to lead the section musically, a well-developed sense of pitch to match low pitched instruments for correct ensemble tuning,  and accuracy in placing pitches to avoid cracked or fractured musical lines.

The second hornist should have strong lower and upper ranges and be a true acrobat on the instrument to jump around registers easily and accurately.  In orchestral ensembles this is the most difficult part in the section technically.  It is also important for this player to match the principal's tone on any horn duets or doubled parts.

A good middle and upper range s desirable for the third horn because it often doubles with the first horn on high, important passages.  Occasionally the third player will have a solo in some orchestral literature, but his main job is as a support part for the principal.  An adequate younger player may be good for following a stronger player's lead.

The fourth hornist should be a low-range specialist to balance the section with sufficient volume.  Power near or above the top of the treble staff is less important because others double these parts.  As the lowest voice of the horn quartet the fourth horn should read bass clef in new and old notation.  New notation is written at the actual pitch while old notation is written an octave lower than actually performed.  Unfortunately, even contemporary composers freely mix both styles.  The best rule of thumb is that if the low horn part has ledger lines below the bass clef staff, it is most likely written in old notation.  The fourth horn player should match the principal's pitch and play out so the remainder of the section can hear down the section to blend and balance the horn quartet.