some common and good mics:
blue snowball
blue yeti
at2020usbplus
at2020usb (version without headphone jack)
atr2500
what i said about them in another thread. you can ignore the behringer one (i just copied the text from the other thread and he had listed that as a possible)
a few notes about each:
behringer c1u
-usb
-decent quality however in general there is lots of talk about the volume levels just being way too low.
-lacks a headphone jack so you cant listen to your voice in headphones without lag
-only has cardioid pickup pattern
audiotechnica atr2500
-usb
-great quality (comparable to the more expensive 2020)
-has a headphone jack for lag free listening to your voice on headphones as you talk
-only has cardioid pickup pattern
samson c01u
-usb
-good quality which is comparable to the blue yeti (though i have to say i prefer the sound of the yeti over this one)
-lacks a headphone jack so you cant listen to your own voice without lag
-only has cardioid pickup pattern
blue snowball
-usb
-good quality. not as nice as the at2020, blue yeti and others but not bad
-lacks a headphone jack so you cant listen to your own voice in headphones without lag
-has 3 pickup patterns for multiple recording scenarios.
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not included on your list:
audiotechnica at2020+ usb
-usb
-great quality similar to atr2500 and blue yeti
-has a headphone jack for lag free listening to your voice on headphones as you talk
-only has cardioid pickup pattern.
blue yeti
-usb
-great quality similar to atr2500 and at2020
-has a headphone jack for lag free listening to your voice on headphones as you talk
-has 3 pickup patterns for multiple recording scenarios
notes:
-cardioid pickup pattern is typically best for picking up voices for commentary as it is limited and helps block out background noise.
-in order to listen to a your voice as you talk in the headset with a usb mic you need it to have a 3.5mm headphone connector
-generally the most respected microphones for youtubers are the at2020 and blue yeti. the blue snowball is often used for upstarts however since it lacks a headphone jack may be outgrown quickly.
if you can manage to stretch your budget a bit the blue yeti is a great microphone and will last you a long time (you shouldnt outgrow it).
if that is out of reach then i would say the atr2500 is a good choice (though it has less options than the yeti). if you dont care about being able to listen to your voice in your headphones then you could likely make do with a blue snowball.
keep in mind you will want to get a pop filter (or make one by stretching pantyhose over a wire frame and putting it in front of the mic).
if you will only use it for voice.... then you only need cardioid mode.
if you want to listen to your voice on your headphones while you talk then you need the 3.5mm headphone plug on the mic
i would highly suggest a shock mount (its mounted in a frame with bungees)
a stand with a moveable arm is the best type to get since its isolated from the desk and can be placed/moved just about anywhere. not as cheap as desk stands though.
my personal favorite is the 2020 but the yeti is very nice too.
on a tight budget the snowball has lots of options but the 2500 is a strong competitor.
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what i said in another post
again, if you dont mind stereo sound i'd go with some nice studio headphones and a desktop mic. a budget of $500max certainly allows that. i'll list a few products to look into. these arent 7.1 units but with the right pc software you could get them to act just like those gaming headsets. the razer gaming software is supposed to do this but i never had it working right (then again my setup is a bit more complex than average).
a few microphones to look into:
blue snowball (somewhat cheap but with alot of features and decent audio quality)
blue yeti (great quality audio and lots of features.
audiotechnica atr2500 (great quality audio but not as many features as the yeti)
audiotechnica at2020 (the 2500 is based on this model. its a great mic but the 2500 is better for value)
a few headphones to look at. keep in mind that closed headphones will isolate you from the outside world as well as preventing people from hearing what is on your headphones and that open headphones will not isolate you from the outside world and people can hear sound leak from them. closed headphones generally have a smaller soundstage while open headphones have a wider one. basically they sound more airy or 3d. open designs will also be cooler to wear than closed ones which may make your ears sweat (the same holds true for headsets too).
open
sennheiser 598 (good soundstage, somewhat low bass, generally good reviews for non bassheads)
beyerdynamic dt880 (good soundstage, decent bass, gets high reviews for gaming)
audiotechnica ad700 (legendary soundstage, not well known for bass, generally good reviews)
closed
beyerdynamic dt770 pro (decent soundstage for closed cans, good bass, great reviews for closed cans)
audiotechnica ath-m50 (small soundstage, great sound for the price, good bass output, very well built)
you could use an external DAC+AMP or soundcard if you're a real audiophile.
even with a mic these options arent likely to top $300-350 total but are good quality equipment.
i didnt mention the dt990 ($350 headphones) but they are a completely open design so have excellent soundstage and great sound. you will be needing an amp though (since i'd go for the 250ohm version). a great set of cans... but not sure if you wanted to spend that much.
i personally own a pair of m50s which are great and i love them though probably not the most ideal choice across the board for gaming unless you wanted something budget friendly. they have great sound and i personally have no qualms with them howver some people say the soundstage is small and they arent good for 3d locating of sound. not a problem i've ever had... but thats what reviews say anways.
also of note is the modmic found here http://www.modmic.com/ which is inexpensive and attaches to studio headphones. generally audio is considered to be good however its not at the same level as some of the better desk mics ($30 compared with $80-150 so you cant really compare)
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in general to pick a mic: do you need to listen to yourself in your headphones? if yes you need one with a mic jack. if no then any will work.
i would say the blue snowball, atr2500 or modmic are all good choices.
in general to pick headphones: how much does "soundstage" matter to you? if you want more 3d-ish sound then open types are best. how much does sound isolation and sound leakage matter? if you want zero leakage and lots of sound isolation then closed are best. what kind of sound profile do you like? some tend towards being bright while others tend to be warm and a bit more bassy.
i personally own ath-m50s and they sound very good for the price (available as low as $99 on ebay) but some say they have a bad soundstage. from the very little gaming i've done on them (they were bought for mostly music) i havent heard any real issues.
the hd598 is highly recommended for gaming because of its wide soundstage but some find the bass a bit weak however perfectly fine for gaming. its an open design though.
if you need closed headphones but want a somewhat wider soundstage then the dt770pro fills that need. its more cost than m50s but has a bit more depth to soundstage. it comes in 3 models (32,80,250ohm) the 250ohm needs an amp or good soundcard but hits the hardest with bass notes.
you can hear a bunch of different headphones here http://www.sonicsense.com/blog/category/open-back-headphones/ to compare how they sound in relation to eachother. scroll down to see the other list (they are divided into open and closed sections)