Yes it is very easy to do. I have two Excals, both have the straight shafts, you only need to reach over and adjust them. To test, grab a broom like it is a shaft, straighten out your arm now reach just behind your elbow if you can touch it, you can adjust it. At the most if your right handed, you can rotate your wrist counter clock wise which twists the controls towards your face.
I moditified the knobs on mine, I replaced the stock knobs for the sense, threshold and the pinpoint/disc to larger scalaped knobs which makes them very east to turn. I never have to adjust the volume, or discrimination so I left them alone.....