I am considering amplifying my harmonicas and flutes but I know next to nothing about amplification. I read Glauber’s post about the Shark DSP-110 and I have been at the mercy of sound techs and crappy microphones for church performances for three years. I’ve had to play with NO monitor because the techs were afraid it would bother the bass player. I’ve had to use omni directional mikes that pick up the sax player, the monitor, breathing, sniffing… I’ve suffered the common problem of having no adjustment in volume between whistle, flute and harmonica, low register, high register etc. I always thought these were unique problems. I’m glad to see they are not.
Here’s what I know: plug mic into amplifier. Turn mic and amplifier on. Play. Adjust knobs as necessary.
Can anyone explain or point me to an explanation of some of the terminology and technology?
What’s a condenser mike do different from a non condenser mike? What is condensing anyway?
Why a preamp. What benefits?
Compression? Gates?
What can I do to plug into the house system that gives me some control.
Look for books and magazines on live sound and recording. There’s a lot to learn.
I’m hoping i’ll be able to try the Shark live on March 5. I’ll report the results. It certainly seemed to work great in my basement. 
2 different technologies, different kinds of electronics. Condensers are more sensitive (in general), but good dynamic (the other kind) mikes have a warmer sound. It boils down to personal preference.
A dynamic (aka diafragm) microphone is like a speaker: the sound moves a membrane that moves a coil over a magnet, generating electrical current. Their main asset is their simplicity. Condenser microphones use condensers (capacitors), whose electrical characteristics vary slightly depending on the air pressure (from the sound) acting on them. They require power (aka phantom power) and amplification, but also work very well.
Why a preamp. What benefits?
The first stage of amplification, between the microphone and the power amp. The preamp will raise the microphone to the same level as keyboards, for example. You always need a preamp, but investing money on a high-quality preamp will give you better sound, because it’s a better quality piece of equipment than what’s built in the mixing console or recorder.
Compression? Gates?
Compression is variable amplification: amplify soft sounds (a lot) more than loud sounds. Necessary for recording to tape, because soft sounds are lost in hiss. Same for broadcast. Some compression is used even in most digital recordings.
Gates: kind of like a switch that cuts the mike off unless there is a certain level of sound coming in. This is good to shut off mikes that are not being used (just picking up background noise).
Another related thing is a low-cut filter, useful to cut down rumble (frequencies that are lower than what your instrument generates).
What can I do to plug into the house system that gives me some control.
Having some kind of preamp (maybe a small mixer) would give you some control, but in the end, if they want to cut you off, they always can. My idea using the Shark (feedback eliminator) is to try to eliminate one of the reasons they may want or need to cut me off.
Here’s an excellent magazine, mostly about recording, but you’ll find a lot of usefull stuff about microphones and sound electronics in there:
http://www.tapeop.com/
Subscription in the US is free!
http://sub.tapeop.com/
This site looks like it has a good amount of information together in one place:
“The Music Edge”
I have no idea who they are (i just googled for “sound reinforcement”), or what their agenda is. But poke around, especially under sound reinforcement.
Thanks for the links Glauber. I also found
this site http://sound.westhost.com/amp-basics.htm and I went to Howstuffworks for the most fundamental description of how amplifiers and microphones work.