Question: Which instrument did In Lingua Mortua use that is similar to the Chamberlin but could be mass-produced more effectively?

Context paragraphs:
Chamberlin Mill Covered Bridge: The Chamberlin (or Chamberlain) Mill Covered Bridge, also called Chamberlin Covered Bridge or Whitcomb Covered Bridge, is a historic covered bridge that carries Chamberlain Bridge Road across the South Wheelock Branch of the Passumpsic River in Lyndon, Vermont.  Built in 1881, it is one of five similar area bridges.  It was listed on the National Register of Historic Places in 1974.

In Lingua Mortua: In Lingua Mortua is a Norwegian band formed by Lars Fredrik Frøislie in 1999 at Hønefoss, Norway.  The music can be described as a mixture of 1970s progressive rock and black metal, and vintage instruments like the Mellotron, Chamberlin, Minimoog, Clavinet and Hammond organ are used frequently, as well as saxophone, bass clarinet, steel guitar, Ludwig drums and Rickenbacker bass.

Trond Bråthen: Trond Bråthen (28 May 1977 – 13 May 2012), also known by the stage names Trondr Nefas and Alastor Nefas, or simply as Nefas, was a Norwegian singer-songwriter, guitarist and bassist.  Despite being primarily known for his work as the vocalist and lead guitarist of black metal band Urgehal, which he founded in 1992 alongside Thomas "Enzifer" Søberg, he had numerous other projects as well, such as Beastcraft (in which he performed as "Alastor Nefas"), In Lingua Mortua, Endezzma (formerly known as Dim Nagel) and Angst Skvadron.  In all of those side projects he collaborated with fellow musician and former Ásmegin member Lars Fredrik Frøislie.

Electric instrument: An electric musical instrument is one in which the use of electric devices determines or affects the sound produced by an instrument.  Electric musical instruments are an example of electric music technology.  It is also known as an amplified musical instrument due to the common utilization of an electronic instrument amplifier to project the intended sound as determined by electric signals from the instrument.  Two common types of instrument amplifiers are the guitar amplifier and the bass amplifier.  This is not the same as an electronic musical instrument, like a synthesizer, which uses entirely electronic means to both create and control sound.

English as a lingua franca: English as a lingua franca (ELF) is the use of the English language as a Koiné language, "a common means of communication for speakers of different first languages".  ELF is also "defined functionally by its use in intercultural communication rather than formally by its reference to native-speaker norms" whereas English as a foreign language aims at meeting native speaker norms and gives prominence to native speaker cultural aspects.  While lingua francas have been used for centuries, what makes ELF a novel phenomenon is the extent to which it is used – both functionally and geographically.  A typical ELF conversation might involve an Italian and a Swede chatting at a coffee break of an international conference held in Brussels, a Spanish tourist asking a local for the way in Berlin, or a Punjabi Indian negotiating with a Tamil Indian salesperson in Chennai.

Instrument Schedule: In theatrical productions, an instrument schedule is a listing of all the lighting instruments and information about them used in a show.  The instruments are organized by their position on-stage, and is the distinguishing characteristic between an instrument schedule and a channel hookup or similar paperwork.  The instrument schedule includes all information about every instrument, including hanging location, instrument number, type, wattage, color, focus area, circuit, dimmer and templates, along with any additional information.  The variety of information included in an instrument schedule generally makes this more "complete" than other generated paperwork, and as such the schedule is often considered the "master" sheet.  The master electrician uses the information contained in the instrument schedule along with the light plot to direct the hanging of the instruments.

Chamberlin: The Chamberlin is an electro-mechanical keyboard instrument that was a precursor to the Mellotron.  It was developed and patented by Wisconsin inventor Harry Chamberlin from 1949 to 1956, when the first model was introduced.  Various models and versions of these Chamberlin music instruments exist.  While most are keyboard-based instruments, there were also early drum machines produced and sold.  Some of these drum patterns feature Harry Chamberlin's son Richard on them.

Mellotron: The Mellotron is an electro-mechanical, polyphonic tape replay keyboard originally developed and built in Birmingham, England, in 1963.  It evolved from a similar instrument, the Chamberlin, but could be mass-produced more effectively.  The instrument works by pulling a section of magnetic tape across a head.  Different portions of the tape can be played to access different sounds.

Magnetometer (Juno): Magnetometer (MAG) is the name of an instrument suite on the "Juno" orbiter for planet Jupiter.  The MAG instrument includes both the Fluxgate Magnetometer (FGM) and Advanced Stellar Compass (ASC) instruments.  There two sets of MAG instrument suites, and they are both positioned on the far end of on three solar panel array booms.  Each MAG instrument suite observes the same swath of Jupiter, and by having two sets of instruments, determining what signal is from the planet and what is from spacecraft is supported.  Avoiding signals from the spacecraft is another reason MAG is placed at the end of the solar panel boom, about 10 m (33 feet) and 12 m (39 feet) away from the central body of the Juno spacecraft.  The MAG instrument is designed to detect the magnetic field of Jupiter, which is one of the largest structures in the Solar System.  If one could see Jupiter's magnetic field from Earth, it would appear five times larger than the full moon in the sky despite being nearly 1700 times farther away.  Jupiter's internal magnetic field prevents the solar wind, a stream of ionized particles emitted by the Sun, from interacting directly with its atmosphere, and instead diverts it away from the planet, effectively creating a cavity in the solar wind flow, called a magnetosphere, composed of a plasma different from that of the solar wind.

Khim: The Khim (Khmer: ឃឹម "Khum";Thai: ขิม, ];) is a stringed musical instrument that is from Persia, called Hammered Dulcimer or Cimbalon.  This Khim was introduced to Cambodia, Laos and Thailand from China, where a similar (though, since the late 20th century, usually larger) instrument is called "yangqin".  This instrument is also known as Santur in India.  It is played with two flexible bamboo sticks with soft leather at the tips to produce a soft tone.  This instrument can be played by either sitting down on the floor with the khim on the floor, or by sitting on a chair or standing while the Khim is on a stand.  The khim produces a bright and expressive sound when played.  It is made of wood, with brass strings that are laid across the instrument.  The Australian-born musician and vocal artist Lisa Gerrard specialises in the use of a khim hammered dulcimer, featuring its music on several albums and performing with the instrument live on tour.

Supporting paragraphs: In Lingua Mortua Mellotron
Answer: The Mellotron