You will definitely want a condenser mic for recording audio at home. So which one is the best condenser mic?
That depends. You didn't think this was going to be easy did you? :-). The first issue is whether you are talking about a large diaphragm condenser mic, or a small diaphragm condenser. If you aren't sure what the difference is, see my article Condenser Vs Dynamic Microphone: What Is The Difference?
Another question you will need to answer is "what are you going to record with this microphone?" If you only have enough in the budget for one mic, I highly recommend a large diaphragm condenser. These are typically the best all-around mics for a home studio.
They are especially great for vocals. But they work well for almost anything else.
So which one is the best? Well you really are not going to get a single answer for this from anyone. First, there are many dozens - maybe even hundreds - of brands and models available. Second, the same microphone might sound great on one person's voice, yet sound terrible on someone else.
Then there is the matter of price. One could say that the "best" mic is the one that costs the most. And in many cases that is true. For example, many professional recording engineers would say that the Neumann U 87 is the best vocal mic ever. But one of those would set you back by $3,200!
You might feel that "best" means best bang for the buck. Something that sounds professional but doesn't cost a million dollars.
So you can see how difficult it is to identify just a single "best condenser mic."
That being said, I can give you a few suggestions based on my own experience.
My suggestions for best condenser mic
My primary large diaphragm condenser mic is the Rode NT2-A. It is a great overall mic, though I use mine primarily for voice recordings (voiceover and singing).
Not only is this an excellent microphone, it is also a multi-pattern mic. That means you can switch the pickup pattern, choosing between cardioid, figure-8 and omnidirectional. For more detail on what that means, see my post Directional And Omnidirectional Microphones - What Are They Good For?
The rode NT2-A goes for about $399.
One other large diaphragm condenser mic I can personally recommend (remember that there are many dozens of these available) is the Audio-Technica AT2035.
This mic is standard in that it is not a multi-pattern mic. It has only one pattern (like most mics) of cardioid. That means that it picks up sound best from directly in front of it, and rejects sound coming from behind it.
The quality of this mic is good. And it costs a lot less than the Rode NT2-A, coming in at about $149. It also comes with its own shock-mount, which is not typically the case with any microphone.
If you have room in the budget for two condenser mics, I recommend adding a small diaphragm condenser. These are especially great for recording acoustic guitar. In fact it's all I ever use for acoustic guitar, and I record my guitar a LOT.
Another really good use of a small diaphragm condenser mic is for narrating "talking-head" videos. If you put one of these slightly above and to the right of you while talking into a camera, the audio will sound MUCH better.
As with LDCs, there are many small diaphragm condensers available. One of the most popular, and the one I use, is the Shure SM81.
All the condenser mics I have mentioned in this post are standard microphones (i.e. not USB mics). Standard XLR (3-pin) microphones require a recording interface. These are (usually) small boxes that you plug the mic into and provide both analog-to-digital conversion (turning your voice into computer language) and preamplification.
You connect your interface to your computer by USB usually. One good choice is the Focusrite Scarlett Solo. This is the one I use. It costs about $110. It has one microphone input. There are other interface units that have 2 or more mic inputs if you need that.
There are so many ways to define "best," so there is no clear answer. But I think I have narrowed it down pretty well for a useful, if not definitive answer. Objectively, if price were no object, the answer is probably the Neumann U87. If you factor in "bang for the buck" (and good enough for most people), I recommend the Rode NT2-A. And if you can afford to have two condensers, I recommend adding the Shure SM81.
You really cannot go too far wrong with any of the mics I have mentioned. they are all great in their own way.