Editing Timpani (section)

== Construction ==
=== Basic timpani ===
The basic timpano consists of a drum head stretched across the opening of a bowl typically made of copper<ref name=bridge/> or, in less expensive models, [[fiberglass]] or [[aluminum]]. In the [[Sachs–Hornbostel|Sachs–Hornbostel classification]], this makes timpani [[membranophone]]s. The head is affixed to a [[wikt:hoop|hoop]] (also called a ''flesh hoop''),<ref name=grove/><ref>{{cite web|url=https://www.merriam-webster.com/dictionary/flesh%20hoop|title=Definition of FLESH HOOP|website=www.merriam-webster.com|language=en|access-date=13 May 2018}}</ref> which in turn is held onto the bowl by a ''counter hoop''.<ref name=grove/><ref>{{cite web|url=https://www.merriam-webster.com/dictionary/counter%20hoop|title=Definition of COUNTER HOOP|website=www.merriam-webster.com|language=en|access-date=13 May 2018}}</ref> The counter hoop is usually held in place with a number of tuning [[screw (simple machine)|screw]]s called ''tension rods'' placed regularly around the circumference. The head's tension can be adjusted by loosening or tightening the rods. Most timpani have six to eight tension rods.<ref name=bridge/>

The shape and material of the bowl's surface help to determine the drum's [[timbre]]. For example, [[Sphere|hemispheric]] bowls produce brighter tones while [[Parabola|parabolic]] bowls produce darker tones.<ref name=power>{{cite journal | last = Power | first = Andrew |date=April 1983 | title = Sound Production of the Timpani, Part 1 | journal = Percussive Notes | volume = 21 | issue = 4 | pages = 62–64 | publisher = [[Percussive Arts Society]] }}</ref> Modern timpani are generally made with copper due to its efficient regulation of internal and external temperatures relative to aluminum and fiberglass.<ref>{{cite web |last1=Jones |first1=Richard K. |title=In Search of the Missing Fundamental |url=https://wtt.pauken.org/?page_id=6785 |website=The Well-Tempered Timpani |access-date=23 September 2018 |date=March 2017}}</ref>

[[File:Timpani setup.jpg|thumb|350px|[[Walter Light]] [[#Pedal timpani|pedal]] and [[#Chain timpani|chain]] timpani set up in three different combinations.]]
Timpani come in a variety of sizes from about {{convert|84|cm|in|order=flip}} in diameter down to ''piccoli timpani'' of {{convert|30|cm|in|order=flip}} or less.<ref name=grove/> A 33-inch drum can produce C<sub>2</sub> (the C below the [[bass clef]]), and specialty piccoli timpani can play up into the [[treble clef]]. In [[Darius Milhaud]]'s 1923 [[ballet]] score ''[[La création du monde]]'', the timpanist must play F{{music|sharp}}<sub>4</sub> (at the bottom of the treble clef).

Each drum typically has a range of a [[perfect fifth]], or seven [[semitone]]s.<ref name=grove/>

=== Machine timpani ===
Changing the pitch of a timpani by turning each tension rod individually is a laborious process. In the late 19th century, mechanical systems to change the tension of the entire head at once were developed. Any timpani equipped with such a system may be considered ''machine timpani'', although this term commonly refers to drums that use a handle connected to a spider-type tuning mechanism.<ref name=bridge/>

==== Pedal timpani ====
By far the most common type of timpani used today are pedal timpani, which allows the tension of the head to be adjusted using a pedal mechanism. Typically, the pedal is connected to the tension screws via an assembly of either [[cast metal]] or metal rods called the ''spider''.

[[File:Dresden pedal.jpg|thumb|left|A pedal on a ''Dresden'' timpano—the clutch (seen here on the left) must be disengaged to change the pitch of the drum.]]
[[File:Timpani, Yamaha pedal timpani.jpg|thumb|The inside, bottom of a Yamaha pedal timpano, showing the mechanical tension-adjusting system]]
There are three types of pedal mechanisms in common use today:
* The ''ratchet clutch'' system uses a [[Ratchet (device)|ratchet and pawl]] to hold the pedal in place. The timpanist must first disengage the clutch before using the pedal to tune the drum. When the desired pitch is achieved, the timpanist must then reengage the clutch. Because the ratchet engages in only a fixed set of positions, the timpanist must fine-tune the drum by means of a fine-tuning handle.
* In the ''balanced action'' system, a spring or [[hydraulic cylinder]] is used to balance the tension on the head so the pedal will stay in position and the head will stay at pitch. The pedal on a balanced action drum is sometimes called a ''floating pedal'' since there is no clutch holding it in place.
* The ''friction clutch'' or ''post and clutch'' system uses a clutch that moves along a post. Disengaging the clutch frees it from the post, allowing the pedal to move without restraint.

Professional-level timpani use either the ratchet or friction system and have copper bowls. These drums can have one of two styles of pedals. The ''Dresden'' pedal is attached at the side nearest the timpanist and is operated by ankle motion. A ''Berlin''-style pedal is attached by means of a long arm to the opposite side of the timpani, and the timpanist must use their entire leg to adjust the pitch. In addition to a pedal, high-end instruments have a hand-operated fine-tuner, which allows the timpanist to make minute pitch adjustments. The pedal is on either the left or right side of the drum depending on the direction of the setup.

Most school bands and orchestras below a [[university]] level use less expensive, more durable timpani with copper, fiberglass, or aluminum bowls. The mechanical parts of these instruments are almost completely contained within the frame and bowl. They may use any of the pedal mechanisms, though the balanced action system is by far the most common, followed by the friction clutch system. Many professionals also use these drums for outdoor performances due to their durability and lighter weight. The pedal is in the center of the drum itself.

=== Chain timpani ===
[[File:Chain timpani.jpg|thumb|220px|On chain timpani, a chain links the tension rods so a master handle can be used to turn them all at once.]]
On ''chain timpani'', the tension rods are connected by a [[roller chain]] much like the one found on a [[bicycle]], though some manufacturers have used other materials, including [[Wire rope|steel cable]]. In these systems, all the tension screws can then be tightened or loosened by one handle. Though far less common than pedal timpani, chain and cable drums still have practical uses. Occasionally, a timpanist is forced to place a drum behind other items, so he cannot reach it with his foot. Professionals may also use exceptionally large or small chain and cable drums for special low or high notes.

=== Other tuning mechanisms ===
A rare tuning mechanism allows the pitch to be changed by rotating the drum itself. A similar system is used on [[rototom]]s. Jenco, a company better known for [[Percussion instrument|mallet percussion]], made timpani tuned in this fashion.

In the early 20th century, Hans Schnellar, the timpanist of the [[Vienna Philharmonic]], developed a tuning mechanism in which the bowl is moved via a handle that connects to the base and the head remains stationary. These instruments are referred to as ''Viennese timpani'' (''Wiener Pauken'') or ''Schnellar timpani''.<ref>[https://web.archive.org/web/20170430020152/http://drtrumpet.eu/MB-PDF/2001e_MB_ISMA_timpani.pdf Vibration patterns and sound analysis of the Viennese Timpani]. Bertsch, Matthias. (2001), Proceedings of ISMA 2001</ref> [[Adams Musical Instruments]] developed a pedal-operated version of this tuning mechanism in the early 21st century.

=== Heads ===
Like most [[drumhead]]s, timpani heads can be made from two materials: animal [[skin]] (typically [[calfskin]] or [[goatskin (material)|goatskin]])<ref name=grove/> or [[plastic]] (typically [[PET film (biaxially oriented)|PET film]]). Plastic heads are durable, weather-resistant, and relatively inexpensive. Thus, they are more commonly used than skin heads. However, many professional timpanists prefer skin heads because they produce a "warmer" [[timbre]]. Timpani heads are determined based on the size of the head, not the bowl. For example, a {{convert|23|in|cm|adj=on}} drum may require a {{convert|25|in|cm|adj=on}} head. This {{convert|2|in|cm|0|adj=on}} size difference has been standardized by most timpani manufacturers since 1978.<ref>[http://www.steveweissmusic.com/product/timpani_head_size/articles "Timpani Head Guide"], ''Steve Weiss Music''</ref>