Now, isn't it the dream of many an instrument maker: to make a saxophone with only open keys?
I mention Sax, Leblanc and Loomis... they all did and so did I. For me, an extra point of departure is the use of only one tone hole per position and not, like my predecessors, to add ever more parallel tone holes – on the contrary I even decided to do away with the existing ones. Naturally, I wanted to retain the layout of the modern mechanism, neither adding nor taking away fingering possibilities.
A first step is made by closing tone holes nrs 8, 13 (side F# and side Bb) in an ordinary modern middle-of-road saxophone and developing a mechanism that substitutes the functions of Ta and Tf. Hole nr 25, the tone hole for F#3, was closed too. Although this tone hole is not inconsistent with the point of departure, it was closed because the place of the hinges of the F#3-mechanism was needed for the new mechanism for Ta and there is always another solution for an F#3.
The slide show goes from top to bottom along the finished instrument.
The example of the Ad Sax 40842 leads to an experiment with another layout of key nr 18.
Key 18 (the "C#-key") is normally being closed by keys 14 and/or 17 and plays the major role in obtaining a C. When this key is linked to key nr 15 (P or the front Bb-key) it is possible to obtain a C and a Bb via the bridge between the right and the left hand key stack. The C is only slightly on the sharp side and very well usable. A small diminishing of the size of hole nr 17 provides a compromise and the C obtained is very well within the margins as we already know them from the fingerings 0,2 and 1,Tc.
Key 16, Tc, is preserved. This key so much has a position of its own, that its function cannot be replaced by another layout of of the mechanism of keys nrs 15 and/or 17.
The new mechanism for Ta functions in a similar vein as the automatic octave mechanism, in which the position of the key depends on two variables, namely on the lever of the second finger left hand and Ta-lever itself. In this case key nr 14 is closed by the second finger left hand – as usual – but only when the Ta is at rest. When the Ta-touchpiece is operated, key nr 14 opens again.
As for fingering, there is no difference here with an ordinary mechanism, but we need a tone hole less.
Key nr 11 (G–G#) too is normally a closed key. The third finger left hand operates key nr 12 and because of the closed position of key nr 11 we still obtain a G. Here too, both keys are changed into open keys and now both need to be closed to get a G. Key 11 can be reopened by the little finger left hand by a similar switch as we use for the Ta-function.
It is not possible in this layout of the mechanism to additionally obtain an Ab as a lowering of an A via the bridge between the right and the left hand, such as for instance Leblanc does in the «le Rationnel» saxophone. This option namely is incompatible with the automatic mechanism of the G# and because this G#-function has in the meantime become an integral part of saxophone mechanisms, it was given precedence over the Ab-option.
Tone hole nr 12 is a rather large tone hole with an built-in cross fingering correction. The size of this hole was reduced to a more normal proportion.
The function of Tf is substituted in quite another way. The method that was used in the Ta-mechanism is not possible, because the first finger right hand sits directly on key nr 9 itself. On the contrary, the Tf-spatula is connected via the back side of the instrument to key nr 10, which, when operated, closes. This means that the semitone is obtained as a flattening of a G and not as a sharpening of an F.
Here too, we use one tone hole less, but the substitute mechanism calls for an adaptation by the musician. On the other hand, new combinations of fingerings arise, since Tf is connected to the bridge between keys nr 10 and 11: the Tf lowers G# to F#, B to Bb and C# to C!
Next key nr 5 (D–Eb) was changed into an open key. Normally, key 5 is a closed key. The third finger right hand closes key nr 6 and because of the closed position of key nr 5 we still obtain a D. Here too, both keys were transformed into open ones and both are closed simultaneously to obtain D. Next, we can again reopen key nr 5 in the normal way by the little finger right hand.
Key nr 5 gets a hinge at the left hand side of the instrument and is connected to key 6 with an arm-and-spring lever in such a way that both keys close at the same time. The spring allows of the key to be reopened. Tone hole nr 6 too is a rather large tone hole with a built-in cross fingering correction. The size of this hole was reduced to a more normal proportion.
Last but not least: key 3 (the "low C#-key") is normally a closed key. This one too was changed into an open key and is now operated by a telescopic linkage to key 4 (the "low C-key"). Here too, the two keys are now being closed at the same time. Next key nr 3 can be reopened in the usual way by the left hand little finger, pushing against the spring tension of the telescope. The fingerings for C# and C thus remain the same.
The linkage between keys 2 and 3 which takes care of key 3 not unwittingly being opened when a low B of Bb is taken, is changed into a linkage between keys 1 and 3.
Was it worth it? Well yes, of course it was, but don't expect miracles. The sound of the instrument especially in the low range is richer and, contrary to my expectations, the sound in general is not brighter, but sweeter, darker (although some changes to the neck might have contributed to that, too). There is not more power to the sound, but the instrument does speak at surprisingly low levels, again, especially in the lower lange.
There are some issues in intonation, especially in the lower end of the second register, which has a stronger tendency to be on the sharp side, despite some corrections in tone holes nr 3 and 6. The tendency is nonetheless not that big as not to be controllable by embouchure.
The mechanisms of both switches (Ta and G#) work flawlessly. The new mechanism of Tf you have to adapt to, but otherwise is more versatile than the conventional layout. The mechanism of D# is slightly heavier to operate. The same holds true for the new mechanism of low C#. All mechanisms do ask for an impeccable padding job and regulation in order to work well.