Quote Pat Nghia Long:
I *experimented* a little with a consumer philips electret (SBC ME 570). Of course it is just not usable because the level of noise is mad, it has very little low end and sounds thin.
Did you put a new battery into it? Those should sound pretty good, it certainly shouldn't have "mad" noise. And it's an omni, so will be great on acoustic guitar.
Keep the Yamaha for funky stuff and treat yourself to an ART Tube MP or Studio V3 microphone amplifier, and and Audio Technica AT2020 for vocal work.
Synths and pianos for Kontakt