Overview

Condenser Microphones are a type of microphone which requires "phantom power" and they are often used for recording sources such as vocals and acoustic guitars. They tend to be considered the most high quality (and most expensive) of microphones with professional studios commonly having condenser mics which cost many thousands of dollars.

Mic Preamps

All condenser mics require "phantom power" which means they all require a mic preamp in order to get any kind of signal out of them. The quality of the mic preamp that you use can greatly effect the quality of the signal that you get into your system. In other words, if you buy a high quality mic, you should get a high quality mic preamp too. One without the other won't do you that much good.

Small Diaphragm vs. Large Diaphragm

There are two large categories of condenser mics: small & large diaphragm. Large diaphragm condenser mics tend to be used for recording vocals (and they also tend to be quite a bit more expensive) while small diaphragm mics tend to be used for recording sources like acoustic guitars. But there are no "set in stone" rules about which type of mic is used for which type of application.

Patterns

There are three recording patterns that a mic can record in: cardioid, figure-8, and omni-directional. A mic will come in one of those patterns or it will be a multi-pattern mic that can be switched between any of these patterns which is preferred because it increases the versatility of the mic as each one of these patterns may be preferred depending on the situation.

With a cardioid pattern a mic records what is directly in front of it while rejecting the sounds that come in from the sides and from the back. This is good for recording just the source with minimal noise. The drawback to this pattern is that it can create an unnatural sound if you are not careful. There is something known as the "proximity effect" which can increase the bass that's recorded. If the mic has a bass roll off switch you will probably want to turn that on if you are recording in this pattern.

With a figure-8 pattern a mic records what is in front and the back while rejecting the sounds from the sides. This can be useful for recording two instruments at once (put the mic in the middle with the musicians facing each other.)

With an omni-directional pattern a mic records all around. This is useful for getting what is known as a "room sound." It can provide the most "natural" sound but it can also pick up more noise. And unless your room is acoustically treated, it's unlikely that it sounds particularly good anyway. It may do more harm to the side than good (this is often the case with home recording studios.)

Low End Condenser Mics (less than $250)

Studio Projects B1
MXL 990
MXL 993
MXL V63M
Octava MK319
Octava MK012
Audio Technica AT3035

Better Condenser Mics ($250-$750)

Rode NTK
Studio Proejcts T3
Josephson C42
Peluso CEMC6

High End Condenser Mics ($750-$1500)

Shure KSM44
AKG C414B
Soundelux U195

Super High End Condenser Mics ($1500+)

Nuemann U87
AKG C12