| Wait a minute: Series choke ballast could work only on AC with voltage about twice the lamp arc voltage or more, so only to the AC mains.
On higher DC voltage (from 4/3 of the arc voltage) the series combination of the choke and resistor (an incandescent,...) would make nice preheat ballast, but as this would be on DC, it would be quiet, regardless how lousy it would be put together. When the supply voltage is large enough, the choke is not needed, but the losses in the resistor would be high.
12VDC is too low to supply the arc, so such ballast always include some sort of inverter. It may be either some electromechanical one (rotary, vibrating) or an electronic solid state one.
The electromechanical inverters would be always loud, as they do contain moving parts, that would always emit some noise. The only way to get rid of it mean hide the inverter into some soundproofed box.
The electronic ones could be made quiet, as they do not have any moving part. Usually operate at few kHz (older units) till few 10's kHz (newer devices). The older, lower frequency tend to whine (the operating frequency match the area of the best sensitivity of human ears), but are very simple and usually work for very long time (the semiconductors have huge margin in switching speed, the line transents are way faster then the operation, so they are filtered by the magnetic components before they reach the semiconductors).
The newer higher frequency ones benefit from operation above the hearing range, but as the semiconductors operate near their limits (slight deterioration of their switching speed, e.g. when heated up by an overvoltage spike, mean huge increase in losses, usually triggering a thermal runaway and destruction; And the disturbances on the supply line are not filtered by the magnetics, as compare to the frequency they are not as fast anymore)
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