Akkordion
System: B-Griff
uni- and bisonoric
(Collection Oriwohl, Nr. IV-65)
Manufacture: Co. Zygmunt Radek (Warschau) presumably around 1910-20 (8,28kg)
This accordion from a Warsaw workshop contains a decisive innovation compared to the two previous instruments, which ultimately gave the accordion the form and function we know today.
Instead of arranging single reeds in one chamber for a 'chamber chord', the valves of separate chambers are connected simultaneously via mechanismal couplings to produce a chord.
The beginnings of this concept probably go back to the Viennese Schrammel harmonica around 1870. There were instruments with twotones as 'chamber chords' which, when combined, made further chords possible. A chord mechanism represents the mechanisation of this basic idea (Graf, p. 69).
The principle machine, which was already the basis of Demian's accordion and also music automatons, becomes an integral part of the accordion.
In principle a forerunner of today's pre-installed harmonies that can be called up with a button on digital instruments and programmes.
Left side, cover removed
The installation of a chord mechanism was only possible in the design of the Viennese model by the necessary space. The manual is divided into two horizontally separated functional areas.
The three lower rows of keys operate the wide valves of the single basses (below).
The upper rows lead via the chord mechanism (thin metal bars, above) to the narrower valves of the chord single tones.
Although there is a handle like on the German model, the internal mechanism corresponds to the Viennese model.
This is because the back of the handle shows that it does not contain any chmbers, but the levers of the keys. The chambers are located as soundposts (right) in the bellows.
The lower half of the key levers lead to the decks of the single basses, the upper half to the chord mechanism.
Chord mechanism with rotatable shafts with soldered levers
A chord formation is shown in red. By pressing the button the vertical lever rotates the shaft slightly and the metal levers attached to it push tiltable wooden levers downwards and lift the valves at the other end (a third is located behind the handle).
With a chord mechanism, multiple tones can be formed from single tones without have to be built into a common chord or be present more than once. Each chord requires a wave, which limits their number.
The bass side therefore remains bisonoric in order to be able to double the number of chords.
Right side, cover removed
B fingering as keyboard system
The three (not visible) rows of keys on the handle correspond to the three vertical rows of valves.
The interior view of the 2-choirs right side
Each soundpost has two 8' choirs which tuned slightly differently (to beat) produce a vibration
The manufacturer in Warsaw (Poland):
"PRACOWNIA HARMONII
RADEK ZYGMUNT
Warzsawa, Al. Jerosolimskie 75/12"
