The action I want is a quick relative tick up or down, then listen again to see if the improvement is adequate, then repeat as necessary until it's perfect.
Sliders are good for quickly moving by a large amount to a rough absolute position. But they're utter crap for fine adjustment.
Am I the only one who gets infuriated when trying to get to the exact spot I want by rolling my finger ever so slightly to get a slider to move by half a pixel? It takes forever and it gives you RSI!