Image that represents the possible registers on the bandoneón. Image that represents the possible registers on the bandoneón.

Bandoneón with registers

Brilliant idea or crazy bulls**t?

The idea of a bandoneón with registers is not new and has been already tested in Germany, especially with the 144 Einheits model. If it seems a strange or unlikely idea, it is due to the fact that the model 142 Rheinische, famous for its unmistakable sound timbre, has risen to sole representative of the entire bandoneón family. This is a misconception, similar to thinking that the Fender Rhodes is the piano par excellence.

By delving a little deeper into the taxonomy of the bandoneons, we discover that the family is very large (someone speaks of more than 60 different types) and over the years several experiments were made. One of these was the application of registers like in the accordion. It is not uncommon to find vintage instruments with registers like this:

Bandoneón AA 144 Einheits with registers, post-war period.
Bandoneón AA 144 Einheits with registers, post-war period.

Or even more ancient, like this one with "manual" registers in the style of diatonic accordion:

Bandoneón H.Band, 1860, with registers (coll. H. Geuns).
Bandoneón "H.Band", 1860, with registers (coll. H. Geuns).

On the bandoneón 142 these experiments have never been done that much because the tango required and still requires just that sound. But thanks to the commitment of many musicians, the bandoneón is showing its potential in other musical contexts as well: hence the need and the desire to explore different timbres.

The concept of register

The concept of register on reed instruments is borrowed from the pipe organ. The groups of voices relating to the various octaves are traditionally named according to pipes' lenght measured in feet, therefore we have 16', 8', 4' and so on. The combination of groups of pipes with different shapes and sizes allows creating distinct sonic timbres. The accordion borrows these denominations to indicate the various groups of reeds that, combined with each other, give different registers and timbres.

The bandoneón is actually quite different, but I borrow the symbols and nomenclatures adopted for the accordion.

Depending on the number of reeds vibrating simultaneously for each key, the accordion (and, by extension, the bandoneón) takes various names. If the reeds vibrating simultaneously are two, it is said that the instrument is in II (this is the case of bandoneón 142). If the reeds vibrating simultaneously are three it called in III. In the bandoneón it is difficult to pass the configuration in III, unlike the accordion where you get to instruments in the V, VI and even in VII.

Bandoneón 142 is in II and presents these 2 "voices":

Register 8' in bandoneón.

8' (real)

Register 4' in bandoneón.


Bandoneón in II: possibles registers

There are 3 possible combinations. The two obvious combinations are the single voices: we have the register at the real octave (called clarinet or flute in the accordion), which we will call 8'; the other register is the upper octave (called piccolo) which we will call 4'.

The third register is given by the superimposition of these two voices. If the reeds are tuned at exact octave distance, this sound corresponds to the typical sound of the bandoneón 142 (on the accordion the combination 8'+4' is called oboe).

Register 8' on bandoneón.

8' (called clarinet or flute)

Register 4' on bandoneón.

4' (called piccolo)

Register 8'+4' on bandoneón.


II or III: which is better?

The bandoneons in III have obviously more possibilities: up to 5-6 possible registers (see below). However, I find it more interesting to apply the registers to an instrument in II, and this for various reasons. First of all to save weight. Secondly, because the tango does not require voices with tremolo, and not even the classical repertoire. So if I'm supposed to play a repertoire that requires voices with tremolo (folk, jazz, etc.), I'd rather buy a good instrument in III to use specifically with that repertoire. The ad sites are full of these bandoneons, many of which are of excellent quality, almost new and at very attractive prices.

To deepen the registers for instruments in III you can see the specific section at the end of the article.

Bandoneón with registers: any appreciable advantages?

A bandoneón with registers would presents these 2 possible advantages:

  • sound advantage;
  • range of notes extension.

Let's see them.

Sound advantage

If you play not only tango but also a different repertoire you may feel the need of different sounds. The presence of the registers on a bandoneón in II would allow you to have 3 registers available on the left side and 3 registers on the right side, bringing the possible combinations to 9. Interesting, isn't it? And don't forget that the bandoneon left keyboard has a cassotto (resonance box), giving a different timbre respect to the right one.

Range of notes extension

Passing from register 8' to 4' it is possible to continue the scale giving an extra octave to the instrument. This is particularly interesting especially for the left keyboard, because it allows you to play several scores from the classical and organ repertoire. The price to pay is that those high notes cannot be played with the typical sound of the bandoneón 142.

Bigger extension of bandoneón left keyboard range of notes, thanks to the registers.

Bandoneón with register: is it worth it?

Are these two appreciable advantages? It depends on how you "use" the bandoneón. Whoever plays tango only will never need registers. Those who instead explore other repertoires might find this implementation interesting.


In order to have an idea of the sound of a bandoneón with one voice it can be useful to listen to its closest relative, the Chemnitzer Concertina. This instrument is quite popular in the USA. In this video we hear Richard Rys playing a Chemnitzer modified by himself. At first an 8' voice is heard (perhaps with slight tremolo), and at a certain point, when he improvises, he switches to voice 4'.


With a relatively simple modification that doesn't add too much weight it is possible to add a feature to the bandoneón, even if, let's clarify it, we encounter less possibilities than more complex and complete instruments, such as the accordion.

Personally I think this is one of the simpler and more immediate directions of evolution: it is a small step to make the bandoneón a more complete instrument and get closer to the concept of concert bandoneón.

Deepening (for nerds): instruments in III

A bandoneón in III typically has the same reeds as the bandoneón in II with a third group of reeds in the real octave but tuned with some Hertz difference, to create the tremolo effect through the acoustic phenomenon of beats (beating voice). So the bandoneons in III (like most 144) typically have these 3 voices:

Register 8' in bandoneón.

8' (real)

Register 8', beating, in bandoneón.

8' beating

Register 4' in bandoneón.


Bandoneón in III: possible registers

The possible registers are the same as above, plus two registers with tremolo: all three reeds together (master register, accordion, musette, etc.) or only the two "real" voices (called violin or celestial depending on whether the beating reed is by excess or by defect). The total in this case is 5 available registers.

Register 8' in bandoneón.

8' (clarinet or flute)

Register 4' in bandoneón.

4' (called piccolo)

Register 8'+4' in bandoneón.


Register musette in bandoneón.

(imitation musette)

Register violin in bandoneón.


Theoretically a sixth register would be possible, 4'+beating 8', but I've never seen it used on accordions.

In this video I play the Canzona nr. 19 by G. Frescobaldi using a 1938 AA bandoneón version 128 tones Einheits. The instrument is in III, with aluminum plates, a slight tremolo and a really interesting sound which in my opinion fits perfectly with this repertoire.



(April 30th, 2021)
A blog reader shared images of his 104-keys König bandoneón, dated around 1930. In the last image is visible the mechanism of the registers.

Bandoneón Konig, 104 keys, around 1930.

Bandoneón Konig, 104 keys, around 1930.

Bandoneón Konig, 104 keys, around 1930.

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