DICTIONARY OF TERMS
Air motor - See wind motor.
Ampico - Name of a type of reproducing player mechanism developed by Charles Stoddard, and manufactured by the American Piano Company.
Bellows - Similar in construction to a pneumatic, only larger (that is, two boards, hinged at one end and covered with bellows cloth). Often used as reservoirs to store suction, or as pumping bellows to evacuate the air from a reservoir, they range in size from 6" wide plus, and 8"-10" long plus.
Bleed - A small, deliberate fixed "leak" that allows a pouch to return more quickly once a hole has passed over the tracker bar, and closed again.
Coin operated piano - A coin operated piano, often with a mandolin attachment but not quite as glorified as an orchestrion.
Deck board - Usually numbering from two to four in a player stack, these boards sometimes contain the valves and almost always are responsible for channeling suction to the striker pneumatics.
Duo-Art - A brand of reproducing player mechanism marketed by the Aeolian Company prior to World War II. Not to be confused with the postwar, standard 88 note player piano marked by Aeolian. Most factory Steinway players were outfitted with Duo-Art player mechanisms. Interesting note - Steinway themselves did not outfit the player mechanisms - the pianos were built by Steinway and sold to the Aeolian Company. All of the Steinway Duo-Arts I have contacted Steinway archives regarding have come back with Aeolian as being the first owner.
End tab - Leading end of a paper roll that hooks onto a tab on the take-up spool.
Expression player piano - A player piano equipped with a mechanism that allows perforations on the paper roll to control the volume level of the piano. It is not as sophisticated as the mechanism on the reproducing piano in that the bass and treble cannot be controlled separately, and generally there are fewer levels of expression. It is however, a system capable of producing quite acceptable dynamics. Often associated with the name Recordo.
Finger - In the inner player mechanism, the device by which movement of the pneumatic is transferred to the piano action. A finger glued to the pneumatic is called the pneumatic finger; a finger located on a rail with other fingers is sometimes called a flanged finger. Flanged fingers often have a screw adjustment called a capstan for adjusting the relationship of the flanged finger to the piano action.
Gasket -Leather packed between two or more sections of a component to facilitate assembly and disassembly of the component while maintaining air-tightness.
Governor - A device that regulates the wind motor, keeping the speed of the wind motor constant even when the suction level in the bellows is fluctuating.
Hinge - Usually made of cotton, a hinge is a piece of cloth that is glued in the hinged end of a pneumatic or bellows, increasing the strength of the pneumatic or bellows.
Inner player - Player piano mechanism contained inside the piano cabinet.
Ladder chain - The type of chain used to transmit power from some transmission gears within the transmission, and often sued to transmit power from the wind motor to the transmission itself.
Mandolin effect - A wooden or light metal bar containing strips of bellows cloth, felt or leather that by means of a lever can be placed between the hammers and strings producing a mandolin or "rinky tink" sound by means of small metal clips driven into the strings by the hammer when the note is played. If not properly made and adjusted a mandolin rail can dramatically increase the rate of wear on the hammers.
Motor driven bellows - Often called the "pump", these bellows are driven by an electric motor rather than by foot pedals. Most common in expensive reproducing pianos and orchestrions.
Nickelodeon - Nickname for an orchestrion.
Orchestrion - Usually coin operated an orchestrion is a player piano that is outfitted with additional automatically controlled instruments such as pipes, xylophones, drums, cymbals, glockenspiels, triangles, wood blocks, tambourines and other instruments and effects. Orchestrions often have beautiful, ornate cases and art glass.
Pallet valve - A simple valve, usually spring loaded, that opens one or more holes when pushed away from its seat by either the operator of the player piano or a pneumatic.
Perforation - A hole in a paper player piano roll.
Player piano - Self playing piano, usually by means of a pneumatic mechanism operated by a paper roll.
Pneumatic - A pair of thin, small (usually less than 3" x 6", in the case of striker pneumatics less than 1 1/2" x 5") wooden boards usually hinged at one end and covered with pneumatic cloth so that when suction is applied, movement opposite the hinged end can be used to play a key, adjust the position of the roll (tracking), control the volume of the piano, or perform some other mechanical function.
Pouch - A small circle (usually 1" - 1 5/8" but often as large as 3" or more) of leather usually 0.10 to 0.12 inches thick that most often is used to activate a valve. Some rare applications use pouches to operate the wind motor or even operate fingers to play the piano keys.
Pumping bellows - bellows that are connected to the pumping pedals, and are used to evacuate air from the reservoir.
Push-up player - See vorsetzer.
Reiterating - Repeating; an example would be the tambourine in an orchestrion. When the pneumatic is actuated, its closing action causes the valve that operates it to shut off, thus causing it to open again. If the perforations in the music roll still indicate that it should be on, it plays again; unlike a striker pneumatic that strikes once and holds while the tracker bar hole to its valve is open. The repeating continues until the perforation in the paper roll closes the hole in the tracker bar.
Recordo - A type of expression player mechanism, not as sophisticated as a reproducing mechanism, but nonetheless able to vary the stack suction (and thus the playback volume) automatically.
Reproducing player piano - A player piano equipped with a mechanism that allows perforations on the paper roll to control the volume level of the piano; bass and treble ends of the piano can be controlled separately.
Reservoir - Large bellows, used to help even out the pulses in suction made by the pumping bellows or motor operated bellows; also stores reserve suction for times when the player mechanism demands it; some pianos will have a suction reservoir and a pressure reservoir, particularly in orchestrions outfitted with pipes or other instruments that use pressure instead of vacuum.
Roll - A length of paper, usually 11 1/4" wide that is perforated with holes usually spaced nine to the inch arranged in a pattern to produce music when played on a player piano. See tracker bar scales for a list of what other sizes and scales rolls have been produced in.
Scroll - Not a proper term, see Roll
Spoolbox - The portion of the player mechanism that houses the tracker bar, tracking mechanism, paper roll, take-up spool, and if equipped, controls for the mandolin and damper pneumatic, among other controls.
Tab - See end tab.
Take-up spool - The spool located in the spoolbox which pulls the paper roll over the tracker bar while the piano is playing.
Tracker bar - A bar, usually made of brass with a series of holes each pertaining to a function of the player mechanism over which the paper player piano roll passes. Found in the spoolbox of the player piano, the tracker bar "reads" the paper as it passes over the bar, and the resulting signals passing through the tracker bar tubing allow the player mechanism to perform functions such as playing a note, playing another instrument such as a triangle or wood block, or performing a function such as raising or lowering the volume of the piano or causing it to rewind the roll.
Tracking - The act of keeping the paper roll in line with the holes in the tracker bar. Often this is accomplished by an automatic tracking mechanism which senses the position of the roll with respect to the tracker bar and adjusts as needed; however, some early player mechanisms and some less expensive later mechanisms require the operator to adjust the tracking with a manual lever.
Transmission - The device that transmits motions of the wind motor and drives the paper roll. Wind motors do not reverse the direction of rotation to rewind the paper roll; that job falls to the transmission.
Unit pneumatic - A pneumatic with all components "built in" so that if servicing a striker pneumatic, the whole pneumatic, valve, valve seats, etc. comes off as a complete unit.
Valve seat - Surface against which a valve contacts. Usually, a valve at rest is against the inner seat, and a valve that is actuated is against the outer seat. Valve seats are usually made of a hard material such as Bakelite or metal, but sometimes the valve is the hard material while the seats are made of leather.
Valve - There are many different types of valves, but they all basically do the same thing - control air flow; whether that be to admit atmosphere into the player system, or to channel or restrict suction within the mechanism itself. More information on valves can be found in the books listed on the resources page.
Vorsetzer - A piano playing mechanism that actually preceded the inner player, vorsetzers were common in the early part of the century. Also called push-up players they could be "pushed up" to a piano, where wooden, felted "fingers" would play a piano keyboard. Usually cumbersome, they were for the most part discontinued after the inner player was developed and gained popularity.
Wind motor - the component in a player piano system that via the transmission is responsible for the movement of the paper player piano roll.
Welte - A brand of reproducing player mechanism developed by M. Welte and Sons in Germany. The Auto Pneumatic Action Company in New York made most of the examples seen in the U.S. today.
Zephyr skin - Extremely thin material made from animal intestinal wall, once used for pouches. Modern zephyr skin is not suitable for pouches, as it splits easily; in addition, insects will eat it if given the opportunity.
Back to the materials page.
Return to the Helpful Information page.