The World's Longest Harpsichord? Johannes Broman's Extraordinary Swedish Experiment

At first glance, Johannes Broman's harpsichord looks almost impossible.

Stretching an astonishing 3.6 metres (nearly 12 feet) from keyboard to tail, it dwarfs even the largest French and Flemish harpsichords. Standing beside it, one immediately wonders why anyone would build such an enormous instrument.

The answer lies not in extravagance, but in science.

Constructed in Stockholm in 1756, Broman's remarkable harpsichord represents one of the most ambitious experiments ever undertaken in the history of keyboard instrument building. Today it is widely regarded as the world's longest surviving eighteenth-century harpsichord, a unique instrument that demonstrates how Enlightenment science and musical craftsmanship could come together in the pursuit of a better sound.

An Extraordinary Commission

The instrument was built by the Swedish maker Johannes Broman at a time when Sweden was embracing the ideals of the Enlightenment.

Rather than simply copying established models from France or the Low Countries, Broman was commissioned to construct an experimental instrument based upon the ideas of Jacob Faggot, an engineer and member of the Royal Swedish Academy of Sciences.

Their goal was ambitious: to rethink one of the fundamental principles of harpsichord design.

Why Is It So Long?

The answer lies in the strings.

In a conventional harpsichord, bass strings become progressively longer towards the lower notes, but practical limits prevent them from increasing indefinitely. Instrument makers therefore adjusted the thickness and material of the strings to achieve the required pitches within a manageable case.

Faggot proposed a completely different solution.

Instead of changing the string gauge significantly, he designed a scaling system in which the string lengths doubled with each descending octave. This mathematical approach required dramatically longer bass strings—and therefore an exceptionally long instrument.

The result was a harpsichord unlike anything seen before or since.

At 3.6 metres in length, it is almost a metre longer than the largest French double-manual harpsichords of the eighteenth century.

Science Meets Music

The project reflects the spirit of the Enlightenment, when scientists and craftsmen increasingly worked together to solve practical problems.

Faggot believed his new scaling system would:

• create a more even relationship between the strings;

• improve tuning stability;

• produce a more consistent tone across the compass;

• simplify aspects of string manufacture.

It was an attempt to apply mathematical principles to musical instrument design—a fascinating example of eighteenth-century scientific thinking.

An Experiment That Failed

Not every experiment succeeds.

Although the concept was ingenious, later study suggests that aspects of the scaling proved impractical. The enormous size created obvious difficulties in construction, while the expected musical advantages failed to outweigh the disadvantages.

No other maker adopted the system.

Rather than becoming the prototype for a new generation of harpsichords, the Broman instrument remained a unique experiment—a remarkable musical dead end.

Yet this is precisely what makes it so valuable today.

A Monument to Innovation

When we think about historical keyboard instruments, it is tempting to imagine that builders simply followed established traditions.

The Broman harpsichord tells a different story.

It reminds us that eighteenth-century makers were capable of remarkable originality. They questioned accepted ideas, collaborated with scientists and sought new ways of improving their instruments.

In this sense, the Broman harpsichord belongs alongside other great experimental instruments of keyboard history: unusual pedal harpsichords, divided keyboards, enharmonic keyboards and the many inventive pianos of the nineteenth century.

A Unique Survivor

Today, Johannes Broman's harpsichord stands as one of the most extraordinary survivors of the eighteenth century.

Its immense proportions immediately capture attention, but its real importance lies beneath the lid. Every inch of its extraordinary length reflects an ambitious attempt to rethink the relationship between mathematics, acoustics and musical performance.

Whether judged as a scientific experiment, a masterpiece of craftsmanship or simply a breathtaking curiosity, the instrument remains one of the most fascinating harpsichords ever built.

More than 250 years after its construction, Broman's giant still asks a question that has inspired instrument makers throughout history:

How far can innovation reshape a familiar instrument?

For Johannes Broman and Jacob Faggot, the answer was nearly twelve feet long.

Credit: Scenkonst Museum