The Sostenuto Pedal

How does the Sostenuto (middle) pedal on a grand piano work? See the mechanism inside the piano:

What do the Pedals on Upright Pianos Do?

The Sostenuto Pedal Piano Control Mechanism

What Are Piano Pedals For? - Hoffman Academy Blog

Piano Pedals – What They Are & How To Use Them

When you have to press down all three pedals at once (dotted line is for sostenuto pedal) : r/piano

Piano Pedals, What Do Piano Pedals Do, Sustain Pedal

Gamechanger Audio Plus Pedal Sustain and Sostenuto Pedal : Musical Instruments

M-Audio SP-Triple Keyboard Sustain/Soft/Sostenuto Pedal

Cincinnati Note: Using the Independent Sostenuto Pedal for Rolled Chords

PS Upright Piano Action - for fastest repetition and sostenuto pedal

How to Work with Pedal Lines in Dorico – OF NOTE

sostenuto pedal markings

Gamechanger Audio Plus Pedal Sustain and Sostenuto Pedal : Musical Instruments

piano - How do I notate for the sostenuto pedal? - Music: Practice & Theory Stack Exchange