illconditioned, please forgive my bluntness but some of your statements are simply not factual, at least not in general. Microphones with internal DC converters (which step up the supply voltage so that it can the be used to polarize the capsule, often at something like 60 VDC) still have a definite range of input voltages that will they work with. Just because a DC converter is part of a microphone circuit is no reason to assume that the microphone will work properly with any other supply voltage than its manufacturer says.
That is even the case with many electret condensers, which nowadays includes some first-quality studio microphones (e.g. DPA). The people who design the electronics for professional quality microphones, particularly in Europe where standards are taken far more seriously than they are here in the U.S., don't figure on amateurs screwing around and guessing at what might work. Phantom powering is an international standard, and when those people design microphones, they assume that the powering will be delivered to the microphone as the standards specify.
In general, by underpowering a microphone you diminish its dynamic range, in some cases quite severely. It becomes less able to handle high sound pressure levels, and may also lose sensitivity and/or have a higher noise floor. What's more, even a relatively small deviation from the tolerances allowed in the standard can have a disproportionately large effect on a microphone's performance--but you might not find that out until the microphone is being used for live recording.
--best regards
Topic: IYO: What is the best most compact phantom power supply? (Read 8663 times)