By the way, it is possible in muO to have that kind of waveform display, 
along with the spectrogram.

Try for example

(AbstractSound bachFugueVoice1On: PluckedSound default) viewSamples

This will yield a zoommable-field morph representing the waveform, where 
click-dragging smoothly scrolls the display, a shift+click-drag smoothly 
scales it (images attached). The right-click menu gives access to the 
FFT settings.

Best,

Stef
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