Mic input to analog pin. What do I need?

I am in tight spot needing swap piezo with mic as a sensor to analog input - rather urgent.
My Piezo has been wired like this(look attached jpg). I can not build any amp for electret mic(as suggested on many discussions) right now. So I tried the amplified mic instead of the piezo into the same resistor, zener, cap configuration. It does solve my problem I had with the piezo however the sensitivity is rather poor. Should I remove resistor-zener-cap from the circuit or there is something else to be aware of(like neg V)? I could use mic through the audio mixer to get good gain though - line level.
Since I can not afford to damage the arduino (if I do something I should not to - no way I can get the replacement right now) so I ask instead.
Otherwise I shall run the show with the piezo.

piezo-wiring.jpg

Well a quick trick you can try is to change the analog reference value to use the internal 1.1vdc reference rather then the default 5vdc reference, that's like amplifying the signal X5 almost.

If you have a Uno type board use analogReference(INTERNAL); in your setup function. If mega type board use analogReference(INTERNAL1V1);

Lefty

Thanks! Should I leave resistor and zener in the wiring as well?

It does solve my problem I had with the piezo however the sensitivity is rather poor.

What was the problem, and how do you measure a sensitivity?

It is a kind of knock sensor. I was reading piezo at every 10ms. Since it puts out a decaying wave - rings like a bell - I can not get just one reading of a given hit and often not at the highest point.
Fir mic hit is a hit and it works as I need. Little sensitivity is not measured - but experienced. I need to knock the mic direct and pretty hard to get high reading.
Actually this tip from lefty solved the issue for the show. Thanks!
And I did connect mic direct to analog pin and ground.
When I get Sparkfun Mic Shields I shall work on these further.