giuliomoro I was reading carefully the blog post that describes how to use piezo mics on bela (the circuit that I am using) and at the chapter (signal conditioning), it says:
To make this easier we first perform some signal conditioning and smoothing to the signal (DC offset filter, full wave rectification and a moving average filter)
.
Tonight I was experimenting with a DC filter and I was able to find a digital solution minimizing this problem by:
1 - Not multipling the signal to boost
2 - Adding a LeakDC and LPF to the signal running basicaly the same previous code:
(
SynthDef("help-AnalogIn",{ arg out=0;
var mic, ampli, freq, hasFreq, sin, flatn, fft,zerox,pitch;
// mic = SoundIn.ar(4,3);
var in1 = LPF.ar(LeakDC.ar(SoundIn.ar(2,1)),1000); // To make this easier we first perform some signal conditioning and smoothing to the signal (DC offset filter, full wave rectification and a moving average filter).
var in2 = LPF.ar(LeakDC.ar(SoundIn.ar(3,1)),1000);
var in3 = LPF.ar(LeakDC.ar(SoundIn.ar(4,1)),1000);
var in4 = LPF.ar(LeakDC.ar(SoundIn.ar(5,1)),1000);
Out.ar([0,1], Mix.new([in1,in2,in3,in4]));
}).send(s);
);
s.sync;
Synth.new("help-AnalogIn", target: s);
I am not sure if that is the result that I should except since the circuit is design to make piezos a trigering sensor for a digital conversion. I am sharing the audio I am getting from this patch below:
With this steps in mind, I wonder now if:
- This circuit is a good alternative for this purpose ( to get a clear audio signal)
- If I can boost the signal adding a preamp on each channel (for example, with the bela multichannel expander)