We are glad to introduce ABACUS, the new flexible and ready-to-use software designed for piano rebuilders, so as to provide an easy way to recalculate and equalize piano string scales.

This application of an Excel® sheet enables you to overview in a few minutes the most critical specifications of the string scaling of the piano you are currently rebuilding, simply by implementing its speaking lengths and diameters.

The datas provided to you by ABACUS are both of acoustical and mechanical interest:

-          Frequency, Inharmonicity of blank and wounded strings, Loudness Factor, Longitudinal Wave;

-          Tensions per strings and per unisons, Total tension in the piano, steel stretch, Steel/Copper Ratio, Percentage to the breaking point according to the type of wire, Average volumic Mass, Transversal Stiffness Factor).

ABACUS also computes the copper winding diameter of the bass strings you wish to use.

It allows you to choose the pitch and the temperament you wish to work with.

An optional computing provides the strike length ratio and the transversal stiffness factor.

Display of ABACUS:

As in any spread sheet, the chart is organized in rows and columns.

The rows relate to the notes of the piano, from A1 to C88.

Generally speaking, the columns written in green color relate to official datas, such as note names and wire numbers.

The columns written in blue are those which you will implement yourself with the lengths and diameter specifications of the piano you are working on: speaking length, wire diameter, total diameter for bass strings, strike point. You may later vary those datas to your specifications.

The columns written in red provide the mechanical results: tensions and percentage to the breaking point.

The columns written in yellow relate to acoustical results: Frequency, Inharmonicity (blank strings and bass strings), Loudness Factor and Longitudinal Vibration.

The columns written in other colors relate to optional or intermediate calculations, such as Copper/Steel Ratio and Copper diameter in orange, or Volumic Mass, Steel stretch, Strike Length Ratio and Transversal Stiffness Factor in purple.

How to use ABACUS:

Plot and implement the speaking lengths and the total diameters (for bass strings) and all wire diameters, as well as the number of strings per unison into the appropriate blue columns, pressing Enter at each implementation, and save your results.

Observe the results in the tension and inharmonicity columns. Those are the most critical ones in the piano rescaling process. Save the original datas in a master copy. Create an other copy for your own corrections. Observe the transition area. Create an Excel® graphic so as to visualize the columns you are the most interested with. Print a shop work sheet.

Enjoy rescaling in a pleasant way!

Price of CD including ABACUS chart for string calculating and complete instruction manual: $ 129.00

A second sheet of ABACUS, providing downbearing calculation using the Lowell® component gauge is available for $ 19.00.

ABACUS  is designed and distributed in the USA and Canada by