Tiptop Audio Fold Processor is a Waveshaper module for modular synthesizers in Eurorack format, the circuit of the voltage-controlled Wave Multiplier and Sub-Octave Generator based on the design of classical diode circuits, which add striking overtones to the input signal through the convolution process and generate rectangle suboctaves.
The Wave Folder creates new waveforms from standard waveforms such as sine, triangle, sawtooth and square. The convolution can be controlled externally via an input with attenuator. The INJECT parameter creates an even larger palette of almost inexhaustible sounds.
The subdivide generator of the Tiptop Audio Fold Processor divides the signals generated by the convolution process into square-wave signals, the intensity of which is controlled in four planes via rotary knobs. The result is output via the SUBDIV output.
Really stable and clean wavefolding with tones ranging from nice FM synth like tones to dirty and angry. This is what I was looking for in the Doepfer A-137-1 module - the capability to get those clean FM-synth like bass sounds. The Doepfer module does get a lot more noisy, which might be something you're interested in though. But as I said, Audio Fold can get dirty and angry as well, especially with the wave multipliers.
Having two inputs also increases your sound shaping capabilities, especially if you want an angrier wavefold sound.
ps. Sounds great when wavefolding Mutable Instruments Rings.