This will not load or distort the signal in any way, nor cause a loss of highs. To tune quietly so that the audience doesn't hear the tuning tones, press the AMP MUTE button. Press it a second time to route the signal on to the amp. Once the note is selected, mode switching is fully automatic. The mode is fast during the initial search for the note.
Most tuners have only one mode, a compromise between speed and accuracy.
This is the only tuner which can provide steady, accurate readings from a signal degraded by hum, hiss, fret buzz, sympathetic vibrations, or leakage from other instruments. This makes it hard to tune accurately. A narrow step means you can easily overshoot the IN TUNE point. If you leave it off longer than a second before turning it back on, normal brightness will return.