The Art of Power Starving

or how to make dead battery music

It has been known since the early days of electronic music electronics that electronic devices likesuch as radios, amplifiersamplifiers, and musical instruments sometimescan produce strangeunusual sound artifacts during power onpower-up and off.
Also,power-down. thatLikewise, battery-powered devices often change their sound sound—or even behave completely differently differently—when the battery goesruns low.

A simple digital  squarewavesquare-wave oscillator makestypically produces a boringdull, nastyharsh beepbeep. sound. ButHowever, when power starving is applied, strangestrange, chaotic noises and selfself-modulation modulationseffects occureemerge, andtransforming the sound changescompletely.

completely.

In recent decades, this phenomenon has led toinspired the development of instruments inwithin the experimental electronic music electronics scene that deliberately exploit thisthe effecteffects of “power starving”.
Thestarving.” insertionA ofcommon technique is to insert a variable resistor,resistor between the (stable) power supply and a simple CMOS oscillator, is widely used.oscillator. This variableresistor—often resistor, also known ascalled a “dead battery potentiometer”, —simulates the increasing internal resistance of a batterydischarging whilebattery. beeingAs discharged.
Thisa means thatresult, power starving can be setcontrolled reproducibly, even within mains-powered instruments or instrumentsdevices fittedequipped with newfresh batteries.

Experiments have shown that it makesis senseuseful not only to add such a "bad“dead battery potentiometer",potentiometer,” but also to make the operating voltage adjustable inwithin thea musically interesting range. ForWhile standard CMOS oscillators, which, in the digital world,oscillators are typically powered with 5..18V5–18 DC,V DC in digital applications, the "“magic range"range” for power starving is much lower, most lower—often between 0.5 and 2.5V5 .
V.

In recent years, the friendsmembers of the Kulturgüterschuppen have dug uprevisited this topic again and madeconducted new experiments.
It turnedThey outfound that a realtrue adjustable current limiter,limiter—also akaknown as a constant current source (CCS), could—can further expand the “sonic possibilities of power starving”starving. sound space. Typical current consumption forSince CMOS oscillators operatedoperating in the magic voltage range istypically justconsume only a few micro amperes, thus we builtmicroamperes, an adjustable current limiter from 0 to 50uA50 µA was developed to generate even more chaotic and unstable noises.sounds.

The real fun begins,begins when power starving is not onlycontrolled statically controlled by potentiometers, but made voltagevoltage-controllable, controllable likeas in analog modular synthesizers. NowThis theallows power starvingpower-starved sounds canto be modulated by any modulationcontrol source, beincluding it self self-modulation feedback, envelopesenvelopes, low-frequency oscillators, or lowcombinations frequency oscillators and any combination with modular synth modules can be made.thereof. Multiple simple power starvingpower-starved oscillators can be patchedinterconnected toin complex, neuralneural-network-like networktopologies, like, topologies forenabling endless sound experiments.

Power starving is not limited to dedicated oscillators. In fact, it can be applied to virtually any electronic musical instrument, instrument—from sound toys,toys circuitand bendedcircuit-bent instrumentsdevices to "Lunetta“Lunetta-style” style" synthesizers is worth to apply power starving. synthesizers. Circuit bending can even be made safer when applyingusing power starving trickstechniques: :reducing lower powerthe supply voltage and/or current limiting reduces the chancecurrent tolowers killthe risk of damaging an instrument whilewhen shorting pins during theexperimentation. bending experiments.Since Lunetta synthssynthesizers already use same or similar CMOS oscillators, soapplying it'spower starving to them is a natural process to power starve them.extension.