A chandelier is a branched ornamental light fixture designed to be mounted on ceilings or walls. Chandeliers are ornate, use incandescent light bulbs, though some modern designs use fluorescent lamps and LEDs. Classic chandeliers have arrays of hanging crystal prisms to illuminate a room with refracted light, while contemporary chandeliers assume a more minimalist design that does not contain prisms and illuminate a room with direct light from the lamps, sometimes equipped with translucent glass covering each lamp. Modern chandeliers have a more modernized design that uses LEDs, combines the elements of both classic and contemporary designs. Chandeliers are distinct from pendant lights, as they consist of multiple lamps and hang in branched frames, whereas pendant lights hang from a single cord and only contain one or two lamps with fewer decorative elements. Due to their size, they are installed in hallways, living rooms, staircases and dining rooms. However, miniature chandeliers exist, allowing them to be installed in smaller spaces such as bedrooms or small living spaces.
Chandeliers were invented during the medieval era. They used candles as their source of light and remained in use until the 18th century, when gas lights superseded by electric lights, were invented; the word chandelier was first known in the English language in the 1736, borrowed from the Old French word chandelier, which comes from the Latin candelabrum. The earliest candle chandeliers were used by the wealthy in medieval times. From the 15th century, more complex forms of chandeliers, based on ring or crown designs, became popular decorative features in palaces and homes of nobility and merchants, their high cost made chandeliers symbols of status. By the early 18th century, ornate cast ormolu forms with long, curved arms and many candles were in the homes of many in the growing merchant class. Neoclassical motifs became an common element in cast metals but in carved and gilded wood. Chandeliers made in this style drew on the aesthetic of ancient Greece and Rome, incorporating clean lines, classical proportions and mythological creatures.
Developments in glassmaking allowed cheaper production of lead crystal, the light scattering properties of which made it a popular addition to the form, leading to the crystal chandelier. During the 18th century glass chandeliers were produced by Bohemians and Venetian glassmakers who were both masters in the art of making chandeliers. Bohemian style was successful across Europe and its biggest draw was the chance to obtain spectacular light refraction due to facets and bevels of crystal prisms; as a reaction to this new taste Italian glass factories in Murano created new kinds of artistic light sources. Since Murano glass was not suitable for faceting, typical work realized at the time in other countries where crystal was used, venetian glassmakers relied upon the unique qualities of their glass. Typical features of a Murano chandelier are the intricate arabesques of leaves and fruits that would be enriched by coloured glass, made possible by the specific type of glass used in Murano; this glass they worked with was so unique, as it was soda glass and was a complete contrast to all different types of glass produced in the world at that time.
An incredible amount of skill and time was required to twist and shape a chandelier. This new type of chandelier was called "ciocca", for the characteristic decorations of glazed polychrome flowers; the most sumptuous of them consisted of a metal frame covered with small elements in blown glass, transparent or colored, with decorations of flowers and leaves, while simpler models had arms made with unique pieces of glass. Their shape was inspired by an original architectural concept: the space on the inside is left empty since decorations are spread all around the central support, distanced from it by the length of the arms. One of the common uses of the huge Murano Chandeliers was the interior lighting of theatres and rooms in important palaces. In the mid-19th century, as gas lighting caught on, branched ceiling fixtures called gasoliers were produced, many candle chandeliers were converted. By the 1890s, with the appearance of electric light, some chandeliers used both electricity; as distribution of electricity widened, supplies became dependable, electric-only chandeliers became standard.
Another portmanteau word, was formed for these, but nowadays they are most called chandeliers. Some are fitted with bulbs shaped to imitate candle flames, for example those shown below in Epsom and Chatsworth, or with bulbs containing a shimmering gas discharge; the world's largest English Glass chandelier, is located in the Dolmabahçe Palace in Istanbul. It weighs 4.5 tons. Dolmabahçe has the largest collection of British and Baccarat crystal chandeliers in the world, one of the great staircases has balusters of Baccarat crystal. More complex and elaborate chandeliers continued to be developed throughout the 18th and 19th centuries, but the widespread introduction of gas and electricity had devalued the chandelier's appeal as a status symbol. Toward the end of the 20th century, chandeliers were used as decorative focal points for rooms, did not illuminate. Adam style A neoclassical styl
The term stained glass can refer to coloured glass as a material or to works created from it. Throughout its thousand-year history, the term has been applied exclusively to the windows of churches and other significant religious buildings. Although traditionally made in flat panels and used as windows, the creations of modern stained glass artists include three-dimensional structures and sculpture. Modern vernacular usage has extended the term "stained glass" to include domestic lead light and objects d'art created from foil glasswork exemplified in the famous lamps of Louis Comfort Tiffany; as a material stained glass is glass, coloured by adding metallic salts during its manufacture. The coloured glass is crafted into stained glass windows in which small pieces of glass are arranged to form patterns or pictures, held together by strips of lead and supported by a rigid frame. Painted details and yellow stain are used to enhance the design; the term stained glass is applied to windows in which the colours have been painted onto the glass and fused to the glass in a kiln.
Stained glass, as an art and a craft, requires the artistic skill to conceive an appropriate and workable design, the engineering skills to assemble the piece. A window must fit snugly into the space for which it is made, must resist wind and rain, especially in the larger windows, must support its own weight. Many large windows have withstood the test of time and remained intact since the Late Middle Ages. In Western Europe they constitute the major form of pictorial art to have survived. In this context, the purpose of a stained glass window is not to allow those within a building to see the world outside or primarily to admit light but rather to control it. For this reason stained glass windows have been described as "illuminated wall decorations"; the design of a window may be figurative. Windows within a building may be thematic, for example: within a church – episodes from the life of Christ. Stained glass is still popular today, but referred to as art glass, it is prevalent in luxury homes, commercial buildings, places of worship.
Artists and companies are contracted to create beautiful art glass ranging from domes, backsplashes, etc. During the late medieval period, glass factories were set up where there was a ready supply of silica, the essential material for glass manufacture. Silica requires a high temperature to melt, something not all glass factories were able to achieve; such materials as potash and lead can be added to lower the melting temperature. Other substances, such as lime, are added to rebuild the weakened network and make the glass more stable. Glass is coloured by adding metallic oxide powders or finely divided metals while it is in a molten state. Copper oxides produce green or bluish green, cobalt makes deep blue, gold produces wine red and violet glass. Much modern red glass is produced using copper, less expensive than gold and gives a brighter, more vermilion shade of red. Glass coloured while in the clay pot in the furnace is known as pot metal glass, as opposed to flashed glass. Using a blow-pipe, a "gather" of molten glass is taken from the pot heating in the furnace.
The gather is formed to a bubble of air blown into it. Using metal tools, molds of wood that have been soaking in water, gravity, the gather is manipulated to form a long, cylindrical shape; as it cools, it is reheated. During the process, the bottom of the cylinder is removed. Once brought to the desired size it is left to cool. One side of the cylinder is opened, it is put into another oven to heat and flatten it, placed in an annealer to cool at a controlled rate, making the material more stable. "Hand-blown" cylinder and crown glass were the types used in ancient stained-glass windows. Stained glass windows were in churches and chapels as well as many more well respected buildings; this hand-blown glass is created by blowing a bubble of air into a gather of molten glass and spinning it, either by hand or on a table that revolves like a potter's wheel. The centrifugal force causes the molten bubble to flatten, it can be cut into small sheets. Glass formed this way can be either coloured and used for stained-glass windows, or uncoloured as seen in small paned windows in 16th- and 17th-century houses.
Concentric, curving waves are characteristic of the process. The center of each piece of glass, known as the "bull's-eye", is subject to less acceleration during spinning, so it remains thicker than the rest of the sheet, it has the distinctive lump of glass left by the "pontil" rod, which holds the glass as it is spun out. This lumpy, refractive quality means the bulls-eyes are less transparent, but they have still been used for windows, both domestic and ecclesiastical. Crown glass is still made today, but not on a large scale. Rolled glass is produced by pouring molten glass onto a metal or graphite table and rolling it into a sheet using a large metal cylinder, similar to rolling out a pie crust; the rolling can be done by machine. Glass can be "double rolled", which means it is passed through two cylinders at once to yield glass of a specified thickness (typically about 1/8" or
A city block, urban block or block is a central element of urban planning and urban design. A city block is the smallest area, surrounded by streets. City blocks are the space for buildings within the street pattern of a city, form the basic unit of a city's urban fabric. City blocks may be subdivided into any number of smaller land lots in private ownership, though in some cases, it may be other forms of tenure. City blocks are built-up to varying degrees and thus form the physical containers or'streetwalls' of public space. Most cities are composed of a lesser variety of sizes and shapes of urban block. For example, many pre-industrial cores of cities in Europe and the Middle-east tend to have irregularly shaped street patterns and urban blocks, while cities based on grids have much more regular arrangements. In most cities of the world that were planned, rather than developing over a long period of time, streets are laid out on a grid plan, so that city blocks are square or rectangular. Using the perimeter block development principle, city blocks are developed so that buildings are located along the perimeter of the block, with entrances facing the street, semi-private courtyards in the rear of the buildings.
This arrangement is intended to provide good social interaction among people. Since the spacing of streets in grid plans varies so among cities, or within cities, it is difficult to generalize about the size of a city block. However, as reference points for US cities, the standard square blocks of Portland and Sacramento are 264 by 264 feet, 330 by 330 feet, 410 by 410 feet respectively. Oblong blocks range in width and length; the standard block in Manhattan is about 264 by 900 feet. S. cities standard blocks are as wide as 660 feet. The blocks in Calgary, are 330 by 560 feet, while those in Edmonton, Canada are 197 by 560 feet; the blocks in central Melbourne, are 330 by 660 feet, formed by splitting the square blocks in an original grid with a narrow street down the middle. In Chicago and Minneapolis, Minnesota, a typical city block is 660 by 330 feet, meaning that 16 east-west blocks or 8 north-south blocks measure one mile. Many world cities have grown by accretion over time rather than being planned from the outset.
For this reason, a regular pattern of square or rectangular city blocks is not so common among European cities, for example. An exception is represented by those cities that were founded as Roman military settlements, that preserve the original grid layout around two main orthogonal axes. One notable example is Italy. Following the example of Philadelphia, New York City adopted the Commissioners' Plan of 1811 for a more extensive grid plan. By the middle of the 20th century, the adoption of the uniform, rectilinear block subsided completely, different layouts prevailed, with random sized and either curvilinear or non-orthogonal blocks and corresponding street patterns. In much of the United States and Canada, the addresses follow a block and lot number system, in which each block of a street is allotted 100 building numbers; the concept of city block can be generalized as a sub-block. A superblock or super-block is an area of urban land bounded by arterial roads, the size of multiple typically-sized city blocks.
Within the superblock, the local road network, if any, is designed to serve local needs only. Within the broad concept of a superblock, various typologies emerge based on the internal road networks within the superblock, their historical context, whether they are auto-centric or pedestrian-centric; the context in which superblocks are being studied or conceived gives rise to varying definitions. An internal road network characterised by cul-de-sacs is typical of auto-centric suburban development in Western countries throughout the 20th century; the Oxford Dictionary of Architecture and Landscape Architecture's definition is rooted within this suburban conception:“Area containing residential accommodation, schools, etc. with public open space, surrounded by roads and penetrated by cul-de-sac service-roads. It is linked to other super-blocks and a town centre by means of paths over or under the roads.”Though the aim of such superblocks is to minimise traffic within the superblock by directing it to arterial roads, the effect in many cases has been to entrench automobile dependence by limiting pedestrian permeability.
Superblocks can contain an orthogonal internal road network, including ones based on a grid plan or quasi-grid plan. This typology is prevalent in China, for example. Chen defines the supergrid and superblock urban morphology in this context as follows:“The Supergrid is a large-scale net of wide roads that defines a series of cells or Superblocks, each containing a network of narrower streets.”Superblocks can be retroactively superimposed on pre-existing grid plan by changing the traffic rules and streetscape of internal streets within the superblock, as in the case of Barcelona’s superilles. Each superilla comprises nine city blocks, with speed limits on the internal roads slowed to 10–20 km/h and through traffic disallowed, with through travel only possible on the perimeter roads. Superblocks were popular during the early and mid-20th century auto-centric suburban development, arising from modernist ideas in architecture and urban planning. Planning in this era was based upon the distance and speed scales for the automobi
An auditorium is a room built to enable an audience to hear and watch performances at venues such as theatres. For movie theatres, the number of auditoriums is expressed as the number of screens. Auditoria can be found in entertainment venues, community halls, theaters, may be used for rehearsal, performing arts productions, or as a learning space; the term is taken from Latin. The audience in a modern theatre are separated from the performers by the proscenium arch, although other types of stage are common; the price charged for seats in each part of the auditorium varies according to the quality of the view of the stage. The seating areas can include some or all of the following: Stalls, orchestra or arena: the lower flat area below or at the same level as the stage. Balconies or galleries: one or more raised seating platforms towards the rear of the auditorium. In larger theatres, multiple levels are stacked vertically behind the stalls; the first level is called the dress circle or grand circle.
The highest platform, or upper circle is sometimes known as the gods in large opera houses, where the seats can be high and a long distance from the stage. Boxes: placed to the front and above the level of the stage, they are separate rooms with an open viewing area which seat only a handful of people. These seats are considered the most prestigious of the house. A state box or royal box is sometimes provided for dignitaries. Seating arrangement: Seating arrangements in an auditorium seating layout will either be identified as “multiple-aisle” or “continental.” These terms are found in design standards manuals, building codes, similar architectural reference documents. Each size is unique, with specific guidelines governing row size, row spacing, exit ways. A multiple-aisle arrangement will have a maximum of 14–16 chairs per row with access to an aisle-way at both ends. In a continental arrangement, all seats are located in a central section. Here the maximum quantity of chairs per row can exceed the limits established in a multiple-aisle arrangement.
In order to compensate for the greater length of rows allowed, building codes will require wider row spacing, wider aisles, strategically located exit doors. Although it would seem like more space is called for, a continental seating plan is not any less efficient than a multiple-aisle arrangement. In fact, if it is planned, a continental arrangement can accommodate more seating within the same space. Sports venues such as stadiums and racetracks have royal boxes or enclosures, for example at the All England Club and Ascot Racecourse, where access is limited to royal families or other distinguished personalities. In other countries, sports venues have luxury boxes, where access is open to anyone who can afford tickets. Auditorium Building List of concert halls Music venue Noise mitigation Performing arts center Smoking ban Concert hall acoustics on-line exhibition
Reinforced concrete is a composite material in which concrete's low tensile strength and ductility are counteracted by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is though not steel reinforcing bars and is embedded passively in the concrete before the concrete sets. Reinforcing schemes are designed to resist tensile stresses in particular regions of the concrete that might cause unacceptable cracking and/or structural failure. Modern reinforced concrete can contain varied reinforcing materials made of steel, polymers or alternate composite material in conjunction with rebar or not. Reinforced concrete may be permanently stressed, so as to improve the behaviour of the final structure under working loads. In the United States, the most common methods of doing this are known as pre-tensioning and post-tensioning. For a strong and durable construction the reinforcement needs to have the following properties at least: High relative strength High toleration of tensile strain Good bond to the concrete, irrespective of pH, similar factors Thermal compatibility, not causing unacceptable stresses in response to changing temperatures.
Durability in the concrete environment, irrespective of corrosion or sustained stress for example. François Coignet was the first to use iron-reinforced concrete as a technique for constructing building structures. In 1853, Coignet built the first iron reinforced concrete structure, a four-story house at 72 rue Charles Michels in the suburbs of Paris. Coignet's descriptions of reinforcing concrete suggests that he did not do it for means of adding strength to the concrete but for keeping walls in monolithic construction from overturning. In 1854, English builder William B. Wilkinson reinforced the concrete roof and floors in the two-storey house he was constructing, his positioning of the reinforcement demonstrated that, unlike his predecessors, he had knowledge of tensile stresses. Joseph Monier was a French gardener of the nineteenth century, a pioneer in the development of structural and reinforced concrete when dissatified with existing materials available for making durable flowerpots, he was granted a patent for reinforced flowerpots by means of mixing a wire mesh to a mortar shell.
In 1877, Monier was granted another patent for a more advanced technique of reinforcing concrete columns and girders with iron rods placed in a grid pattern. Though Monier undoubtedly knew reinforcing concrete would improve its inner cohesion, it is less known if he knew how much reinforcing improved concrete's tensile strength. Before 1877 the use of concrete construction, though dating back to the Roman Empire, having been reintroduced in the early 1800s, was not yet a proven scientific technology. American New Yorker Thaddeus Hyatt published a report titled An Account of Some Experiments with Portland-Cement-Concrete Combined with Iron as a Building Material, with Reference to Economy of Metal in Construction and for Security against Fire in the Making of Roofs and Walking Surfaces where he reported his experiments on the behavior of reinforced concrete, his work played a major role in the evolution of concrete construction as a proven and studied science. Without Hyatt's work, more dangerous trial and error methods would have been depended on for the advancement in the technology.
Ernest L. Ransome was an English-born engineer and early innovator of the reinforced concrete techniques in the end of the 19th century. With the knowledge of reinforced concrete developed during the previous 50 years, Ransome innovated nearly all styles and techniques of the previous known inventors of reinforced concrete. Ransome's key innovation was to twist the reinforcing steel bar improving bonding with the concrete. Gaining increasing fame from his concrete constructed buildings, Ransome was able to build two of the first reinforced concrete bridges in North America. One of the first concrete buildings constructed in the United States, was a private home, designed by William Ward in 1871; the home was designed to be fireproof for his wife. G. A. Wayss was a pioneer of the iron and steel concrete construction. In 1879, Wayss bought the German rights to Monier's patents and in 1884, he started the first commercial use for reinforced concrete in his firm Wayss & Freytag. Up until the 1890s, Wayss and his firm contributed to the advancement of Monier's system of reinforcing and established it as a well-developed scientific technology.
One of the first skyscrapers made with reinforced concrete was the 16-story Ingalls Building in Cincinnati, constructed in 1904. The first reinforced concrete building in Southern California was the Laughlin Annex in Downtown Los Angeles, constructed in 1905. In 1906, 16 building permits were issued for reinforced concrete buildings in the City of Los Angeles, including the Temple Auditorium and 8-story Hayward Hotel. On April 18, 1906 a magnitude 7.8 earthquake struck San Francisco. The strong ground shaking and subsequent fire killed thousands; the use of reinforced concrete after the earthquake was promoted within the U. S. construction industry due to its non-combustibility and perceived superior seismic performance relative to masonry. In 1906, a partial collapse of the Bixby Hotel in Long Beach killed 10 workers during construction when shoring was removed prematurely; this event spurred a scrutiny of concrete erection practices and building inspections. The structure was constructed of reinforced concrete frames with hollow clay tile ribbed flooring and hollow clay
New Objectivity (architecture)
The New Objectivity is a name given to the Modern architecture that emerged in Europe German-speaking Europe, in the 1920s and 30s. It is frequently called Neues Bauen; the New Objectivity remodeled many German cities in this period. The earliest examples of the style date to before the First World War, under the auspices of the Deutscher Werkbund's attempt to provide a Modern face for Germany. Many of the architects who would become associated with the New Objectivity were practicing in a similar manner in the 1910s, using glass surfaces and severe geometric compositions. Examples of this include Walter Gropius and Adolf Meyer's 1911 Fagus Factory or Hans Poelzig's 1912 department store in Breslau. However, in the aftermath of the war these architects worked in the revolutionary Arbeitsrat für Kunst, pioneering Expressionist architecture—particularly through the secret Glass Chain group; the early works of the Bauhaus, such as the Sommerfeld House, were in this vein. Expressionism's dynamism and use of glass would be a mainstay of the New Objectivity.
The turn from Expressionism towards the more familiarly Modernist styles of the mid-late 1920s came under the influence of the Dutch avant-garde De Stijl, whose architects such as Jan Wils and JJP Oud had adapted ideas derived from Frank Lloyd Wright into cubic social housing, inflected with what Theo van Doesburg called'the machine aesthetic'. Steering German architects away from Expressionism was the influence of Constructivism of VKhUTEMAS and El Lissitzky, who stayed in Berlin during the early 1920s. Another element was the work in France of Le Corbusier, such as the proposals for the concrete'Citrohan' house. In addition, Erich Mendelsohn had been veering away from Expressionism towards more streamlined, dynamic forms, such as in his Mossehaus newspaper offices and the Gliwice Weichsmann factory, both 1921–2; the earliest examples of the'New Building' in Germany were at the 1922 Bauhaus exhibition, Georg Muche's Haus am Horn, in the same year, Gropius/Meyer's design for Chicago's Tribune Tower competition.
However the fullest early exploration of a new, non-expressionist avant-garde idiom was in the 1923–24'Italienischer Garten' in Celle by Otto Haesler. This was the first Modernist'Siedlung', an area of new-build social housing characterised by flat roofs, an irregular, asymmetrical plan, with houses arranged in south-facing terraces with generous windows and rendered surfaces. Contrary to the'white box' idea popularised by the International Style, these were painted in bright colors; the strongest proponent of color among the housing architects was Bruno Taut. The major expansion of this came with the appointment of Ernst May to the position of city architect and planner by the Social Democratic administration of Frankfurt-am-Main. May was trained by the British garden city planner Raymond Unwin, his Estates showed garden city influence in their use of open space: however they repudiated the nostalgic style of Unwin's projects such as Hampstead Garden Suburb. May's'New Frankfurt' would be enormously important for the subsequent development of the New Objectivity, not only because of its striking appearance but in its success in re-housing thousands of the city's poor.
However their advanced techniques alienated the building profession, much of whom were made superfluous by the lack of ornament and speed of construction. May would employ other architects in Frankfurt such as Margarete Schütte-Lihotzky and Mart Stam; the immediate effect of May's work can be seen in Gropius's 1926 Torten Estate in Dessau, which pioneered prefabrication technology. That Germany had become the centre of the New Building—as it was called, in preference to'the New Architecture'—was confirmed by the Werkbund's Weissenhof Estate of 1927, where despite the presence of Le Corbusier and JJP Oud, most of the architects were German speaking. Further Werkbund Estate-exhibitions were mounted in Vienna in subsequent years; the architects of the New Objectivity were eager to build as much cost-effective housing as possible to address Germany's postwar housing crisis, to fulfill the promise of Article 155 of the 1919 Weimar Constitution, which provided for "a healthy dwelling" for all Germans.
This phrase drove the technical definition of Existenzminimum in terms of minimally-acceptable floorspace, fresh air, access to green space, access to transit, other such resident issues. At the same time there was a massive expansion of the style across German cities. In Berlin, architect-planner Martin Wagner worked with the former Expressionists Bruno Taut and Hugo Häring on colourful developments of flats and terraced houses such as the 1925 Horseshoe Estate, the 1926'Uncle Tom's Cabin' and the 1929'Carl-Legien-Siedlung', through the auspices of the Trade Unionist building society GEHAG. Taut's designs featured controversially modern flat roofs, humane access to sun and gardens, generous amenities like gas, electric light, bathrooms. Critics on the political Right complained that these developments were too opulent for'simple people'; the progressive Berlin mayor Gustav Böss defended them: "We want to bring the lower levels of society higher." Similar experiments in municipal socialism such as the Viennese Gemeindebau were more stylistically eclecti
A choir is a musical ensemble of singers. Choral music, in turn, is the music written for such an ensemble to perform. Choirs may perform music from the classical music repertoire, which spans from the medieval era to the present, or popular music repertoire. Most choirs are led by a conductor, who leads the performances with face gestures. A body of singers who perform together as a group is called a chorus; the former term is often applied to groups affiliated with a church and the second to groups that perform in theatres or concert halls, but this distinction is far from rigid. Choirs may sing without instrumental accompaniment, with the accompaniment of a piano or pipe organ, with a small ensemble, or with a full orchestra of 70 to 100 musicians; the term "Choir" has the secondary definition of a subset of an ensemble. In typical 18th- to 21st-century oratorios and masses, chorus or choir is understood to imply more than one singer per part, in contrast to the quartet of soloists featured in these works.
Choirs are led by a conductor or choirmaster. Most choirs consist of four sections intended to sing in four part harmony, but there is no limit to the number of possible parts as long as there is a singer available to sing the part: Thomas Tallis wrote a 40-part motet entitled Spem in alium, for eight choirs of five parts each. Other than four, the most common number of parts are three, five and eight. Choirs can sing without instrumental accompaniment. Singing without accompaniment is called a cappella singing. Accompanying instruments vary from only one instrument to a full orchestra of 70 to 100 musicians. Many choirs perform in many locations such as a church, opera house, or school hall. In some cases choirs join up to become one "mass" choir. In this case they provide a series of songs or musical works to celebrate and provide entertainment to others. Conducting is the art of directing a musical performance, such as a choral concert, by way of visible gestures with the hands, arms and head.
The primary duties of the conductor or choirmaster are to unify performers, set the tempo, execute clear preparations and beats, to listen critically and shape the sound of the ensemble. The conductor or choral director stands on a raised platform and he or she may or may not use a baton. In the 2010s, most conductors do not play an instrument when conducting, although in earlier periods of classical music history, leading an ensemble while playing an instrument was common. In Baroque music from the 1600s to the 1750s, conductors performing in the 2010s may lead an ensemble while playing a harpsichord or the violin. Conducting while playing a piano may be done with musical theatre pit orchestras. Communication is non-verbal during a performance. However, in rehearsals, the conductor will give verbal instructions to the ensemble, since they also serve as an artistic director who crafts the ensemble's interpretation of the music. Conductors act as guides to the choirs they conduct, they choose the works to be performed and study their scores, to which they may make certain adjustments, work out their interpretation, relay their vision to the singers.
Choral conductors may have to conduct instrumental ensembles such as orchestras if the choir is singing a piece for choir and orchestra. They may attend to organizational matters, such as scheduling rehearsals, planning a concert season, hearing auditions, promoting their ensemble in the media. Eastern Orthodox churches, some American Protestant groups, traditional synagogues do not use instruments. In churches of the Western Rite the accompanying instrument is the organ, although in colonial America, the Moravian Church used groups of strings and winds. Many churches which use a contemporary worship format use a small amplified band to accompany the singing, Roman Catholic Churches may use, at their discretion, additional orchestral accompaniment. In addition to leading of singing in which the congregation participates, such as hymns and service music, some church choirs sing full liturgies, including propers. Chief among these are the Roman Catholic churches. Mixed choirs; this is the most common type consisting of soprano, alto and bass voices abbreviate