| Instrument | violin |
| Aubert number | 5 |
| Quality grade | entry grade |
| Model | French |
| Condition | Blank, uncut |
| Material | Maple |
| Country of manufacture | France |
The violin bridge passes the force of the bowed string, which contains every partial (overtone), on to the top plate filtered through its own resonances. Its two main modes (natural patterns of vibration) lie around 3 kHz, where the head of the bridge rotates about its waist and couples into the top through the feet, and around 6 kHz, where it bounces on its legs at right angles to the top.
The broad rise between 1.5 and 4 kHz shown by fine Italian violins (the bridge hill) is attributed to the bridge resonance, and this band is also where our hearing is most sensitive. As little as 0.5 g of added mass on the bridge shifts this resonance measurably downwards.
As guide figures for a 4/4 violin, the bridge stands around 33 mm high at the centre, with a foot width of 41 mm, a thickness at the chest of 4.5 mm and a projection of 27.5 mm; the strings cross the bridge at an angle of around 157°. With the Thomastik synthetic sets we stock, the strings press the bridge onto the top with around 8.5 to 9.5 kg. The right foot stands above the sound post and acts as a pivot; below around 700 Hz the bridge rocks about this foot, and the left foot above the bass bar passes most of the energy on to the top plate.
The maple of a bridge blank (density around 650 kg/m³) is around five times as stiff in bending along the grain as across it. Modulus of elasticity and damping (how quickly a vibration dies away in the wood) vary from tree to tree by around ±25 and ±50 per cent, so that even boards from the same tree turn out differently.
Aubert sorts its blanks into quality grades that can be read from the number; the pattern carries its own marker, such as the B for the Belgian model. 'Aubert Mirecourt' is the house stamp and at the same time the name of the basic grade; above it come 'Luxe' and, as the highest of the grades we carry, 'De Luxe', recognisable by the L in the number.
Our experience: we always cut and fit a violin bridge individually to its instrument before it is sent out. In our work plan for a 4/4 violin the bridge is allotted around six hours, three of them for the feet alone. We cut the string notches to one third of the string diameter.
For an instrument on the level of our Golden State and Cantonate violins we recommend the Aubert De Luxe ZR-8L, which we fit there ourselves; on Metropol, Menuett, Antique, Agape and Audition we use the Aubert Luxe ZR-8.
Around 8.5 to 9.5 kg press it onto the top, with the four strings pulling around 21 to 23.5 kg in total with the Thomastik synthetic sets we stock. With the factory set Dominant 135 in medium that is 21.2 kg of tension and around 8.5 kg of load.
Yes, it can, because bridge mass, tuning and the fit of the feet directly affect what the bridge passes on to the top plate. A change in bridge mass of just 0.5 g is measurable.
It denotes the quality grade of the blank. Above the basic grade 'Aubert Mirecourt' come 'Luxe' and 'De Luxe'; the L in the number stands for De Luxe.
Because every bridge is fitted to its own instrument: the violin maker sets the feet, height, thickness and curve on the instrument itself. How well the feet fit the top plate helps determine how the vibration is transmitted.
No, Aubert marks its grades by number and name. We know stars as a grading mark from other makers, Teller bridges for example.
These texts hold decades of experience and a great deal of heart. They are protected by copyright, C.A. Götz jr. GmbH. Please ask us before any use. Thank you for your appreciation.