This video takes a look at ‘no-input mixing’ – the idea that you can use feedback loops within mixers to generate sound.
Most users try to avoid noise when mixing. No-input mixing is about embracing the noise inherent in mixers and using it to synthesize sound.
No Input Mixing
How does this work?
Here’s an explanation via the Department of Performance Studies at Texas A&M:
Two facts allow an audio mixing console to become a synthesizer without any other inputs, when you put it in a feedback loop (meaning you feed its output to its own input):
1) Mixers contain amplifiers that make weak sound stronger, and
2) No audio hardware is perfectly silent; it is always introducing a (hopefully small) level of noise into your signal.
Put these two facts together in a feedback loop, and the mixer amplifies its own system noise, allowing it to bloom into its own full voice.
The mixer can then shape that voice with its rich filter (EQ) and signal-routing options. Volume and filter controls can gradually add or remove resistance to certain modes of resonance (acting a bit like a trombone slide) and signal routing switches can quickly redirect a signal through a path with different properties (somewhat like the valves of a trumpet).
If you want to try no-input mixing, they recommend using it with gear that you can live without, because you could potentially damage the mixer or your speakers with extreme signal levels.
The video demo is via The Tuesday Night Machines. Gear used:
- Behringer Eurorack UB1202 Mixer
- Thomann t.mix 802 Mixer (discontinued)
- Zoom R16 (recording)
Have you tried no-input mixing? If so, leave a comment and let us know what you’ve tried!