However, for this application the decay time setting is also important. With a long decay, the gate may remain open during the space between notes, which doesn't allow a new attack to be triggered when a new note plays. Electronically speaking, the noise gate is now a pseudo-comparator. Each waveform becomes a square wave as it falls below the threshold, while the peak remains unmodified. At low thresholds, you'll hear an occasional buzz.
Higher thresholds can give mean, nasty, spiky sounds.
The digital mixer itself may even include a test tone oscillator. Patch the kick drum into the gate's key input and set the threshold relatively high, so that the kick exceeds the threshold for only a very short amount of time. Set the noise gate decay for the desired amount of oscillator decay. Hopefully your gate decay can go up to about two seconds, but even one second can do the job. This realtime performance tip can sound very cool with hip-hop, techno, and other types of music that rely on variations within drum loops.