Solid Gold FX Funkzilla All-analog signal path, powerful filter matrix, and unique Tap Tempo control with filter modulation. Standard controls for Frequency and Depth make it easy to quickly shape the character of the filter. The Attack knob lets you dial in the filters response to your instrument. Also includes a Direction toggle, shared by both Envelope and Tap modes, giving you the ability to set the direction of the filter sweep. The custom Tap Tempo function with tap multiplier takes your filter control even further: offering multiple waveform settings, expression pedal input, and dynamic rhythmic patterns.