David Gritter
1477 W. Harbour Towne Cir.
Muskegon, MI 49441
Description
The Gritter Residence organ is an electronic organ consisting of a Rodgers organ console, a midi interface, and a personal computer for sound generation. The console has three manuals and pedal, and includes a single level combination action with moving stop tabs, using the Rodgers CORE memory based system. Expression shoes are provided for Choir, Swell, and Crescendo. Tabs are available to allow the pedal to be un-enclosed, or enclosed with the Swell, or the Choir. A lighted pushbutton transposer is also included. The original console circuitry is used for scanning the keyboards, stop rail, and expression pedals, so the intra and inter manual couplers continue to operate. The console emits a serial bitstream of data, originally intended for interpretation by the remote racks of electronics that originally generated the electronic sounds and controlled the pipes.
The midi interface is a custom designed microcontroller (similar to Arduino boards) which accepts the serial bitstream from the console and converts it into midi note on/off and midi controller messages.
The personal computer is a standard IBM compatible PC running a 64 bit Linux operating system. Organ control and sound generation is by way of an open source application called GrandOrgue. This application interprets midi messages to turn stops on and off, and to respond to keyboard messages. Sound is generated using samples from real pipe organs, typically using individual samples for each note in a rank. Samples from multiple commercial and creative commons organ sample sets were chosen to create a disposition similar to the original disposition of the Rodgers Organ. The software can also load standard organ definitions files and samples to re-create the sounds of existing pipe organs.
Each rank is routed to one of 8 audio channels where it is captured by an open source audio routing software called JackAudio. JackAudio routes the audio channel to an appropriate audio amplifier, and to a subwoofer capable or reproducing 32′ stop sounds, and to a reverberation program. The open source reverberation program, jconvolver, accepts impulse response files typically generated by firing a starter pistol or popping a balloon inside a real church or auditorium space.
17 audio channels are available, of which eight are used for direct sound from the ranks, one for a subwoofer, and two for reverberation. The direct sound speakers are located at each side of the console, and the reverberation speakers are located at the opposite side of the room from the console.
History
The original organ was one of the first combined electronic/pipe organs, a Rodgers Gemini, from 1972. It was installed and used in a Roman Catholic church in the St. Paul – Minneapolis area. The pipes were manufactured by Ruffatti and consisted of the Great Principal8, Octave 4, and Doublette 2 ranks; an 8′ Trumpet rank for the Great, and a unit flute rank for the Great 8,4,and 2′ flutes. The Great Fourniture IV was created electrically by multiplexing the Diapason ranks. All other organ ranks were electronic, with 7 ranks of individual tone generators.
When the Russian state returned an historic church building to the catholic church in Vladivostok, Russia, on the north shore of the Sea of Japan, a Catholic mission was founded in the church. A 1973 Rodgers organ was donated to the church, and it turned out that this was the only organ for hundreds of miles. An organ concert program became wildly popular, and the analog electronic organ was eventually replaced with a Rodgers Trillium digital organ. Shortly after this, the mission persuaded the owners of the Rodgers Gemini organ to donate it to the Vladivostok mission, so that the pipes could be added to the Trillium organ. The remainder of the organ remained in storage in Minneapolis, and was advertised as available to a good home. Mr Gritter had to be interviewed by the priest in Vladivostok, and promise to restore the organ to operating condition, using the original analog sound generators. Thereupon the organ was donated to Mr Gritter, along with more than 30 speakers, including a 24 inch diameter sub-woofer in an enclosure the size of a refrigerator. Restoration was done, with digital electronic stops for the Great, but the organ proved to be too difficult to maintain in tune, so eventually the personal computer sound generator was substituted for all ranks.
Rodgers Organ company was founded in1958 by two engineers who were employees of Tektronix, Inc., a highly regarded manufacturer of test equipment, particularly oscilloscopes. Rodgers used multiple ranks of transistor oscillators, and were proud of the ensemble sound that resulted. They were highly innovative, using computer core memory for combination actions in 1966, reed switches for pedal contacts in 1961, and incorporation of midi in 1986. Rodgers has built many combination pipe/electronic organs since the Gemini series began the practice, and even provided a few entirely pipe based organs. Virgil Fox was associated with Rodgers for some years, and had a touring organ that used the same technology as is in the Gemini Organ.
Rodgers became part of CBS in 1977, along with Steinway Pianos, Gemeinhardt flutes, and a few other well known instrument brands. In 1985 CBS divested itself of these instrument companies, and in 1988 Rodgers became a subsidiary of Roland corporation. Rodgers has been owned, since 2016 by the same organization that controls Johannus Organs Company in the Netherlands.
Photos
Please click on any photo to bring up a slideshow.
- Console, speakers, and computer for digital sound generation
- Combination action at the top of the organ console
- Core memory for combination action
- GrandOrgue screen layout of keyboards and stops.
- Audio connection scheme with reverberation.
- The original 11 racks of analog electronic sound generators and pipe drivers.
- Some of the original pipes as seen in Vladivostok, Russia
- Display pipes in Vladivostok, Russia
- Residence
Media Files
Stoplist
Great
Gedeckt Pommer 16′
Principal 8′
Gemshorn 8′
Gamba 8′
Concert Flute 8′
Rohrflute 8′
Octave 4′
Spitzflute 4′
Nazard 2 2/3 ‘
Fifteenth 2′
Waldflute 2’
Fourniture IV
Trompet 8′
Tremulant
Solo (floating)
Doppelflute 8′
Quintadena 8′
Cornet IV
Contra Trompette 16′
Trompette en Chamade 8′
Clairon en Chamade 4′
Vox Humana 8′
Tremulant
Swell
Contra Salicional 16′
Viola Pomposa 8′
Viola Celeste 8′
Gedeckt 8′
Geigen Principal 8′
Principal 4′
Nachthorn 4′
Nasat 2 2/3 ‘
Gemshorn 2’
Terz 1-3/5 ‘
Cymbale III
Basson 16′
Trompette 8′
Hautbois 8′
Clairon 4′
Tremulant
Strings (floating)
Salicional 8′
Salicional Celeste
Fugara 8′
Dolce 8′
Viol de Gamba 8′
Salicet 4′
Fugara 4′
Tremulant
Choir
Erzahler 8′
Erzahler Celeste
Singend Gedeckt 8′
Principalino 4′
Koppelflute 4′
Octave 2′
Blockflute 2′
Larigot 1 1/3 ‘
Sifflute 1’
Scharf IV
Dulzian 16′
Krummhorn 8′
Regal 8′
RohrSchalmei 4′
Tremulant
Positive (Floating)
Gedackt 8′
Rohrflute 4′
Principal 2′
Quinte 1 1/3 ‘
Octave 1’
Schalmei 8′
Pedal
Contra Bourdon 32′
Principal 16′
Subbass 16′
Violone 16′
Lieblich Gedeckt 16′
Octave 8′
Gedeckt 8′
Choral Bass 4′
Flute 4′
Octavin 2′
Mixture II
Contra Bombarde 32′
Posaune 16′
Dulzian 16′
Trumpet 8′
Krummhorn 4′
Zink 2′
Pedal enclosed by Choir
Pedal enclosed by Swell