The Sostenuto Pedal

Steinway's third pedal held only the notes already down, sustaining a bass without blurring what came next.

Related

RomanticSostenutoPiano

The right pedal on a piano holds every note at once, and a neighbour chord turns the harmony to mud. The middle pedal took another route, holding only the notes already down when it was pressed, leaving later notes clean.

Time and place

New York, around 1874. Steinway patented a selective sustaining device, usually credited to Albert Steinway. Other makers offered similar mechanisms, but on many European pianos the middle pedal is a moderator or a bass sustain rather than a true sostenuto.

What happened

The mechanism is a bar that rises when the pedal is pressed and catches the dampers already lifted, so they cannot fall back. Notes played afterwards keep their normal damping and sound dry. A player can therefore let a bass note or a chord ring while playing staccato or fast figures above it. The patent appeared in the 1870s, but the three-pedal layout became standard much later, and only in the twentieth century did pianos commonly carry all three.

What changed

The piano gained a way of layering its texture, with a sustained note, a harmonic layer and a melody each going their own way. Composers began writing passages that only the middle pedal can realise cleanly, and twentieth-century scores occasionally mark it. Control became more refined, since sustaining was no longer an all-or-nothing switch. On the other hand, the middle pedal was never uniform across countries, and the same music behaves differently on different instruments, so touring pianists learned to check the piano in advance.

Listen for the turn

Begin with Debussy's Pagodes, where the bass holds while figures move above; the damper pedal would smear the harmony together, while a sostenuto would keep only the bass. Then Ravel's Le gibet, a bell-like note sounding through the whole piece while other voices move around it, and hear how that note escapes being swallowed. Finally Liszt's Un sospiro, the pedal joining arpeggios into one sheet of sound with the bass supporting the melody. All three use the damper pedal; the middle pedal solves the same problem, but note by note.

Related

This turn belongs to Romantic; see Sostenuto, Piano.

Sources

• Grove Music Online, entry Sostenuto pedal — patent and mechanism checked, not quoted
• The New Grove Dictionary of Music and Musicians, 2nd ed., entry Pianoforte — pedal history checked, not quoted

Used for fact-checking only; all prose is original.