A collection of simple music circuits, oscillators, filters, envelopes etc., simulated online. To see the circuits, browse to the simulator, right click on it, choose the circuits sub-menu then select a circuit. You can build your own circuits in the applet too. Please send your music circits, suggestions or corrections to me, Ollie
Follow @musiccircuits on Twitter to see when circuits are added or updated.
The simulator works best on a large monitor as some circuits are quite large. You can choose to a smaller size if you need to.
Full size (1400 x 820 widescreen)
Medium size (1000 x 800)
Small size (800 x 600)
To save your circuits, right click on the simulator, select "File", "Export", then copy the text. Email it to me for inclusion on the site.
I've recreated the circuit schematics with as few changes as possible. Sometimes I have to change the layout, as the simulator's 555 IC has unusual pin locations and no ground pin. Occasionally I've added a 1Ω resistor, as the simulator requires resistors to be present in some loops containing capacitors.
Some circuits work, some work partially or not at all. If you can debug them or identify issues in with the simulator, please let me know.
Amplifies and adds a bias to an AC signal, making it DC and ensuring there are is no negative voltage in the output.
This circuit shows how different capacitors change the filter's cutoff.
An active low pass filter in the Sallen-Key topology.
The LPF section from Ray Wilson's Weird Sound Generator.
comrade_zero's LPF.
The simulator doesn't have the parts for this filter but I tried to build it anyway; it doesn't work. There are two outputs, bandpass and lowpass.
Seems to work but only on the first wave. Not sure I have all of the output in the right place, nor if all of the inputs are correct.
This ingeniously simple circuit uses the 555 timer IC. The attack and sustain work but it's not clear if the sustain and release are functioning correctly.
Partially functioning, this circuit's attack works but the envelope doesn't decay or release.
Another 555 timer circuit, even simpler than René's but not working.
Generates a ramp or sawtooth LFO with adjustable frequency.
The addition of another switch between the ramp / saw toggle and the 1KΩ resisitor adds triangle wave output.
A triangle wave LFO with adjustable shape. Hold the switch for a couple of seconds to start the circuit, this adjustment to the circuit is necessary because the simulator doesn't model the effect of turning the power on.
Sine, triangle and pulse out of this 5 volt, 741 op-amp LFO.
