The Boardwalk Hall Auditorium Organ, also known as the Midmer-Losh and the Poseidon, is the pipe organ in the Main Auditorium of the landmark Boardwalk Hall (formerly known as Convention Hall) in Atlantic City, New Jersey. The musically versatile instrument was built by the Midmer-Losh Organ Company during 1929–1932. It is the largest organ in the world, as measured by the number of pipes – officially 33,112, but the exact number is uncertain. After decades of accumulated damage from water, building renovations, neglect, and insufficient funding, beginning in the 1990s a $100 million restoration program is gradually returning the organ to full operability.
The Main Auditorium was built as the world's largest unobstructed indoor space, a barrel vault measuring and enclosing of air. The Auditorium Organ runs on much higher wind pressures than most organs, to be loud enough to fill the enormous space acoustically without amplification.
The organ was awarded four entries in Guinness World Records, including the largest and loudest musical instrument ever constructed. It is one of only two organs in the world to have an open 64-foot pipe rank, and the only organ to have pipes voiced on 100 inches of wind pressure (3.6 psi or 0.25 atm) and a console featuring 7 manuals and 1,235 stoptabs.
Construction and layout Construction of the organ took place from May 1929 through December 1932, shortly after the hall was built. The organ was designed by state senator Emerson Lewis Richards of Atlantic City and musician and inventor Seibert Losh and was built by the Midmer-Losh Organ Company of Merrick, New York, as its opus 5550. Most of the pipes were handmade by Midmer-Losh. Pennsylvania-based Anton Gottfried made some of the reed pipes, including the Brass Trumpet, Egyptian Horn, Euphone and Musette Mirabilis. The German firm Welte-Mignon provided the Bassoon with papier-mâché resonators and the wooden Tuba d'Amour for the Echo division.
The organ is built around the Main Auditorium of Boardwalk Hall, although no pipes are visible from the public space. The organ's pipe divisions are distributed across eight chambers behind the auditorium walls: Left StagePedal Left,Unenclosed Choir,Swell, String I,Swell-ChoirStageRight StagePedal Right,Percussion,Great, Solo,Great-Solo (Flues),Great-Solo (Reeds)Left ForwardChoirRight ForwardBrass Chorus,String II Left CenterGallery III (Diapasons),Gallery IV (Orchestral)Left UpperFanfare,String IIIThe Upper chambers are located above the Center chambersRight UpperEchoRight CenterGallery I (Reeds),Gallery II (Flutes)
The current layout of the organ was Emerson Richards' third proposed design. The first design was to house 43,000 pipes in six chambers (all mentioned above without the two Forward chambers), but the quoted cost greatly exceeded the allocated $300,000, and there wasn't enough space to house all the pipes. The number of pipes was then reduced to 29,000. Later, when the Forward chambers were also used, some pipes from the original plan were reinstated, raising the number to the present official count of 33,112. The Upper chambers were placed in the ceiling above the Center chambers, as placing them any further back would result in synchronization issues due to the speed of sound, which takes nearly half a second to travel the length of the arena. Asbestos was used extensively, which would later complicate maintenance. The final contract price was $347,200, signed shortly before the Great Depression, [1st ed. 2002, ] .
Console The organ's main console is one of the largest in the world. It has 1,235 stoptabs (many unified, "borrowing" from the same pipe ranks) including 587 flue stoptabs, 265 reed stoptabs, 35 melodic percussions, 46 non-melodic percussions, 164 couplers, 18 tremulants, 120 selectors for the 6 swell pedals controlling 15 swell boxes, and a crescendo pedal.
The console is the one of the only ones in the world with 7 manuals. Uniquely, the lowest two (Choir and Great) have a range of seven octaves, and the third-lowest (Swell) has a range of six octaves, while the rest have a normal five-octave range. The bottom five keys on the Swell manual (GGG to BBB) are in place mainly for cosmetic reasons, as most ranks have no pipes for these notes; however, they would sound if couplers were activated. The manuals from top to bottom are:
VIIBombard 5 octaves, 61 keys, CC to c4VI Echo 5 octaves, 61 keys, CC to c4V Fanfare 5 octaves, 61 keys, CC to c4IV Solo 5 octaves, 61 keys, CC to c4IIISwell 6 octaves, 73 keys, GGG to g4II Great 7 octaves, 85 keys, CCC to c5I Choir 7 octaves, 85 keys, CCC to c5
The Great and Choir manuals were designed with seven octaves so that specially extended stops (tone selections) in the pedal can be played throughout the 85-note compass of both manuals, comparable to the range of a piano. These stops can be selected by stoptabs in two divisions on the right stop jamb. The Grand Great (for the Great manual) controls stops from the Pedal Right pipe division, and the Grand Choir (for the Choir manual) controls stops from the Pedal Left pipe division. For example, the Grand Ophicleide pipes can be played from the pedalboard, and also from the Great manual by means of the Grand Great.
Likewise, some pipe divisions are independently playable on two manuals. For example, the Choir-Swell division is usually played from the Choir manual (I), but it has been "duplexed" to the Swell manual (III), stoptab for stoptab. In this way, the division's stops are also available there as the Swell-Choir, no matter which stops are selected for the Choir manual. The same is true for the Great-Solo pipes, which are usually played from the Great manual (II), but can also be selected as the Solo-Great for the Solo manual (IV).
The pedalboard and the Great and Choir manuals are equipped with "Second Touch", allowing the organist to use two different voicings by pressing the same key to different depths.
Although the four Gallery divisions (when repaired) can be played from any manual, their "home" is the Bombard manual (VII). They are the only pipe divisions playable from it, and its keyslip contains the divisional pistons for setting combinations of the Gallery stops.
An older and smaller (5-manual) console is on display in the lobby outside the auditorium, no longer connected to the instrument. Since 2019, the 7-manual main console is named in honor of Frederick R. Haas, whose family foundation has supported the Midmer-Losh and other important pipe organs in the region.
Stops
Stephen D. Smith, president of the former Atlantic City Convention Hall Organ Society, comprehensively reviewed the Main Auditorium's organ stops in his 2002/2010 book and subsequent web updates, including "compound" Celeste and Mixture stops that are each built with multiple pipe ranks. His unofficial estimate of 33,116 pipes has the following distribution:
+ Stoplist SummaryPipe division Voices Ranks Pipes Pedal Right 11 11 903 Pedal Left 10 16 955 Choir 29 37 2,792 Unenclosed Choir 6 9 657 Great 38 63 4,647 Great-Solo (Flues) 13 13 1,152 Great-Solo (Reeds) 12 12 972 Swell 36 55 4,456 Swell-Choir 17 17 1,542 Solo 22 33 2,085 Fanfare 21 36 2,364 Echo 22 27 1,898 Gallery I 4 10 754 Gallery II 7 9 621 Gallery III 6 9 681 Gallery IV 8 8 596 Brass Chorus 8 10 730 String I 11 20 1,436 String II 24 37 2,658 String III 9 17 1,217 Total 314 449 33,116
In addition to the 314 stops controlling the pipe ranks summarized above, the instrument also has 23 percussion voices (16 non-melodic and 7 melodic, including a motorized grand piano), for a total of 337 stops. It includes clear principal choruses and mixtures that are typical of German Baroque organs, and imitative orchestral stops typical of symphonic organs, and also the percussion division and extended ranks and "Second Touch" typical of theatre organs. Even before high-quality recorded music was available, this versatile blend of organ features would let the Midmer-Losh convincingly deliver a wide variety of music, for the countless performers and events that would use the multi-purpose Main Auditorium.
64-foot Diaphone-Dulzian Boardwalk Hall possesses a unique stop in the organ world, the 64-foot Diaphone-Dulzian in the Right Stage chamber (Pedal Right division), one of only two full-length 64-foot stops in the world. The stop is unique, because it is a reed/diaphone hybrid. (The other 64-foot stop is the Contra-Trombone reed stop in the Sydney Town Hall Grand Organ, built in 1890.)
When construction of the Auditorium Organ started, it was planned to have two 64-foot stops in the pedal, a Diaphone Profunda and a Dulzian, in the Right Stage and Left Stage chambers respectively. Later, the design was revised, and the Diaphone was omitted because it was feared it would crowd the Right Stage chamber. Consequently, the Dulzian was moved to the Right Stage chamber. However, the sound of the 64-foot Dulzian did not meet the tonal criteria, requiring Diaphone pipes to be used for the lowest 22 notes, after much experimentation. The remaining pipes in the rank are reeds. Because of the low frequencies involved, and because the diaphone is voiced to imitate a reed stop, the transition from reed to diaphone cannot be detected. (For several decades, diaphone technology was also used for foghorns.)
The Diaphone-Dulzian's low-C pipe is in length, has an upper width and a base mechanism that are each nearly , and weighs . It produces a frequency of 8 Hz, a tone that is more felt than heard, five octaves below middle C. The sound of the vibrating pallet is described as "a helicopter hovering over the building". The wooden pipe is upright for about , the remainder is mitered (angled) towards the Right Stage chamber grille, like an upside-down L. All pipes taller than were designed in this manner. The two lowest pipes (CCCCC and CCCCC#) are fed by a single, dedicated 8-inch diameter wind line, operating on 35 inches of pressure. A second identical wind line feeds the remaining pipes.
The Diaphone-Dulzian is sufficiently extended so that 64-, 32-, 16-, 8- and 4-foot unison stops, and -foot, -foot and -foot mutation stops, may be drawn from the same rank of pipes. Also, when the 64-foot and -foot are combined, the resultant tone simulates a 128-foot stop, equivalent to 4 Hz on low C.
Use of the Diaphone-Dulzian is rare, being used primarily in registrations of moderate volume. In very big combinations it is lost, and in smaller ones it is too loud. Nonetheless, when the stop was first tested in 1930, it caused tiles to fall from the auditorium ceiling and structural elements of the building to rattle.
32-foot stops To provide the power needed in the pedal, the organ has ten 32-foot stops: Stop Division Tibia Clausa 32' Pedal Right Bombardon 32' Pedal Right Diaphone 32' Pedal Left Diapason 32' Pedal Left Bombard 32' Pedal Left Fagotto 32' Pedal Left Sub Principal 32' Great Trombone 32' Fanfare Violone 32' Echo Diaphone-Dulzian 32' (extension of 64') Pedal Right
Grand Ophicleide The Grand Ophicleide in the organ's Pedal Right division, behind the Right Stage chamber grille, speaking on 100" wind pressure, was recognized by Guinness World Records as the loudest organ stop in the world. It is described as having "a pure trumpet note of ear-splitting volume, more than six times the volume of the loudest locomotive whistle." The Grand Ophicleide produces up to 130 decibels at a distance of 1 meter, and is designed to be heard throughout the auditorium over any other stops that might be playing. The pipes were built by Roscoe Evans, who served as the organ's first curator.