You have something wrong with your circuit. Post your schematic.
I have an LM386 with its gain set to 200 with a 10uf capacitor between pin 1 and pin 8. My electret mic is biased with a 10k resistor from the positive supply and is coupled to the LM386 input with a 0.22uF coupling capacitor feeding a 100k volume control. It is so loud that I turn down the volume control.
Audioguru, if you don't mind indulging me a moment, I've got a few questions/comments that might take us on a bit of a tangent in this conversation.
1. Regarding that schematic: you didn't draw that, right? It looks a lot like the National Semi style of schematics one sees in books, etc. (I think it's National Semicircular, anyhow.) I happen to like that style of schematic drawing (planning on starting a thread about schematics here soon).
2. In that circuit, a couple of things bug me. First of all, what's the purpose of that 1K resistor and 100uF cap there on the left? Power-supply decoupling? Why not just leave them out and run the 10k resistor right from V+?
Also, what's the purpose of the small (,047uF) cap and 10-ohm resistor on the output? Shouldn't the 8-ohm speaker load be sufficient (through the coupling cap, of course)?
3. Strictly speaking I wouldn't say that the electret is "biased" by the 10K resistor: it's actually
powered by it, right? AFAIK, electrets (usually) contain a FET amplifier, no?
4. Interesting that you say it's loud enough to have to turn down the volume. Those op amps are pretty amazing devices. But again strictly speaking, shouldn't we be talking about the output in terms of power (watts, or at least milliwatts), and not in terms of voltage, since we're using this as a power amp?
5. Finally, isn't it a bit ridiculous to be using a puny op amp for such an application? When the OP posed a question about a PA system, I ass-u-med that they were asking about a proper PA, one that could actually be used to, well, address the public. This clearly won't do it; how come nobody has pointed that out?
Not meaning to knock ya, but I like to point out these things when I encounter them.