Magnus Harmonica Grand Electric Chord Organ model #700, 1970s, made in Belgium

 1959 year's made in USA

The Magnus Harmonica Corporation was founded in Linden, New Jersey around 1944. Magnus sold and distributed children's harmonicas and Mechanical Reed Organs. In the 1950's, Magnus introduced Electric Reed Organs and continued producing harmonicas.  In the 1960's, Magnus introduced their famous Electric Chord Organs to compete with Hammond.  These are still considered Reed Organs, the name was changed to Chord Organs because the included playable chord pads unlike their older siblings.  Sometime in the early 1970's, the company's name was changed to Magnus Organ Corporation.  Magnus also made a few 'real' electric organs that were not reed organs.  Magnus sales slumped with the post-oil embargo recession and finally went out of business around 1977.  These little organs appeared in many households at the time, and were considered beginners instruments, not toys.  They now lie derelict in thrift stores, at yard sales, and lonely on eBay.  All records and information on the Magnus Corporation were lost in time, long before the creation of the internet or this website.  After countless hours of research, trips to the US Patent Office, and personal investigation the information on these pages has been constructed.

So, what IS a Magnus Chord Organ... how do they work?

Simple, these are your basic reed organ.  They use a pump (an electric fan on older models) to blow air across reeds, like a giant harmonica with keys or an accordion.  They are VERY simple and primitive machines, being easy to repair.  The later models are called 'chord organs' because they have chord buttons to be played with the left hand, emulating how a piano player plays with their left hand.  Remember, these were beginners instruments used often in instruction.  The music books that came with the organs are written both in music, and by number.  Each note was assigned a number (instead of a letter) 1 instead of C, and accidentals being noted as 1+ instead of C#.

If we remove the case, we find a fan, ductwork, and a reed board.

  

Here's another shot of the main board from a three octave model ( ~2ft legnth):

Notice the three sections containing 12 reeds each, each section is one octave, each reed is one of the 12 notes in that octave... simple!

The chords work the same exact way.  Since this machine is so primitive, there are three reeds for each chord corresponding to each of the three notes in that chord (triad).

Most models have six major chords: Bb - F - C - G-  D - A

This corresponds to the key signature, starting with two flats going to three sharps, (the range that most popular music uses).  On the models equipped with minor chords, the process is identical.

So, that's what's inside, but how do they make noise?

These work identically to the reed organs of the late 1800s, there is just an electric fan to move the air instead of pumping bellows.  Remember, Magnus built harmonicas; In a harmonica, you use your mouth to blow air thru a channel where a specific reed is positioned.  The airflow causes that reed to vibrate, and depending on the size and thickness of that reed, a certain note is produced.

An accordion works the exact same way except it has keys to uncover the reed channels instead of you having to move your mouth around.  It uses a bag (bellows) to pump up air to move past the reeds, as do these ancient reed organs.  The Magnus Chord Organ works identically.  It uses a fan that blows air thru a duct to the reed boards.  All of these reeds vibrate, but air can not get past them until you press the correct key and the reed vent is uncovered, letting that note speak.  See below:

 You notice the three left keys are mashed, uncovering that particular channels vent.  The two keys on the right are not pressed, and the foam under the key seals off the vent so that no air may escape from that channel, keeping those note from playing.  These are considered free reed aerophones, like an accordion, and they sound similar.

Hear the sound of a Magnus Chord Organ: wav File, 2MB

See the Inside Movie (1:45): mov File, 2.7MB