This group contains just two controls, an illuminated T-Bar, and a button labeled +/-. Adjustments to T-Bar position progressively modify playback speed, and can also automatically engage playback when not already in progress.
Since, at a given moment, Channel A and B may well be set to different playback speeds, the T-Bar position may not initially reflect the correct speed when you change which channel is delegated.
In this case, the speed applied updates as soon as you move the T-Bar to (or through) the current speed. (When a newly delegated source is at 0% speed – whether due to pressing STOP or T-Bar use – the initial T-bar position is ignored when you push PLAY and playback commences at 100% speed.)
In normal operating mode, the maximum T-Bar position corresponds to 100% playback speed, with 0% at the opposite extreme of the lever’s travel. Pressing +/- engages a special T-Bar mode to extend the T-Bar’s range. In this mode, the top and bottom of the lever stroke represent +200% and -200% respectively, with 0% (playback stopped) in the middle.