 `${lineType.id}-preview`;
        pianoRoll.className = 'piano-roll-preview';
        previewColumn.appendChild(pianoRoll);

        // Add event listeners
        activeCheckbox.addEventListener('change', updateControls);

        // Combine columns
        section.appendChild(controlsColumn);
        section.appendChild(previewColumn);

        return section;
    }

    // Load the instruments asynchronously
    function loadInstruments() {
        showLoading(true);
        Promise.all([
            So