Try "Set range to full spectrum".
You used to be able to drag-stretch the spectrum about before it was released, which I preferred (I set from red at lowest frequency to blue at highest, rather than from red to red with the above preset), but that doesn't seem possible anymore
Maybe we should submit an FR for it? "Half range to full spectrum"..?
Edit: yes it is possible, position the mouse over the right-hand border of the spectrum and drag the edge to "stretch" the spectrum out. Position the red at the LF end and streth the red to lie at the HF end. Is that what you wanted?
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