I just plugged a cheap piezo contact directly into the Plaits level in and am blown away. Not only is it velocity sensitive with no gain for the transducer needed, but it basically acts as a preamp (processing audio through the algorithms. Did I somehow miss this in the documentation? It seems to work in most green and red modes. Are the Rings modes effectively the same as an actual Rings, in that one can use their own exciters into the level?
The LEVEL input does exactly what is mentioned in the documentation: Opens the internal low-pass gate, to simultaneously control the amplitude and brightness of the output signal
It’s not processing audio through the algorithms, just modifying their brightness and amplitude proportionally to the voltage received on the LEVEL input.
I’m not sure how this could be called a “preamp”. It has the regular 100k input impedance, and no gain – pretty much like any CV input.
In the case of the piezzo it just works because:
- The piezzo can generate quite high voltages, up to 10V, and this is precisely the range expected for this input (8V = full ammplitude).
- The LEVEL input is unipolar, so effectively, the signal from the piezzo is half-wave rectified.
- The response of the LEVEL input emulates (in software) that of a vactrol, so this acts as a kind of envelope follower with an audio or fast-changing signal.
Maybe you should explore patching the piezzo to other CV inputs – it will behave exactly the same way!
- If TRIG is patched, the LEVEL input controls the amplitude of the internal exciter.
- If TRIG is not patched, the LEVEL input controls the amplitude of the output signal (equivalent to post-processing the signal with a VCA).
In both cases, the excitation signal is still internally generated.