TaiChiCali,
What I do, is just use a cheap lapel mic (costing a dollar or two from China, MLE mentions one in his first post, I bought and have found acceptable one on Amazon with a "Neweer" brand name) and a cheap 2.5mm to 3.5mm adapter to plug the mic into my Xbox 360 controller. Then, I set chat audio to play through the "speakers" (hit the guide button>settings>preferences>voice>"Play through Speakers" option), so I hear everything in my headphones and have an independent mic clipped to my shirt that doesn't pick up breathing
I have also had equivalent success with 2.5mm jack wired cellphone earpieces, like the Platronics MX210 that I just sort of stick onto my shirt collar with the boom mic pointing up.
Of your 3 headphones, I would personally be torn between the M-100 and HE 400. I've been following the M-100 thread, and of course read MLE's glowing impression of the HE's (with velour pads) since he got 'em. I used to have a pair or Crossfade LPs (still own them, they've GOT to be around somewhere!), they had better than average soundstage for a closed headphone, but a somewhat dark and rather bass-heavy sound signature. The M-100 from all accounts would be more balanced than the LPs, with a milder but still boosted bass and more treble brightness and extension, and better for gaming and all-around use (including portable), but it still is more of a "fun" headphone headphone rather than audiophile in signature. The HE400, I'm guessing, has the best sound quality of all the headphones you mentioned, while also having a more audiophile "flavor." It's not going to be something you can take around campus, though. It's your choice and your taste in the end, though. Personally, I chose to buy a used Q701 and use my Crossfade LPs for a portable, but since I can't find those I'll probably on stick with... Well, I game mostly with my Q701 now.
SoAmusing777,
Welcome to Head-Fi, sorry about your wallet!
I personally say Receivers have a great long-sighted value if you can physically fit them into your gaming space. You get a decent solid-state amp, hook ups for Hi-Fi speakers, a touch of EQ for your headphones, remote, input switcher so you can keep various systems hooked up to your TV, all the sound codecs you need (like DTS and Dolby Digital), an external DAC, an fm radio tuner, etc... To be honest, you will be hard pressed to hear a difference between HDMI and Optical (it's like slightly softer, I barely make it out with my Q701s), so either should be fine. Dolby Digital is nothing to sneeze at, but of course the receiver will (probably) understand most types of DTS signals too.
To explain one thing, after the receiver, uh, receives either a DTS or Dolby Digital signal from your console, it processes the signal inside the receiver's DAC, and if you have headphones plugged in it will then simulate surround sound using a processing algorithm like Dolby Headphone, or some other manufacturer's proprietary algorithm (like Yamaha's "Silent Cinema"). If you want the Dolby Headphone version of headphone surround in a receiver, you'll have to find an older model of Harman Kardon receiver, apparently. Newer versions have HK's own version of headphone surround... which I personally haven't heard if it's better or worse.
I
have a Yamaha receiver with Silent Cinema... It's pretty good, positioning is pretty accurate, though when you use DSPs it sounds like you're in a cave, of varying size. There is also Dolby Pro Logic (forget what version) as an alternative to Silent Cinema built-in... Positional accuracy isn't as good because it mixes surround from stereo audio (so that's like... 5/7.1-->stereo-->5.1-->virtual surround), but for all that it actually
sounds alright. Good for RPGs and situations where accuracy isn't so important, YMMV. I haven't decided if I best like a DSP with lowered effect strength (cuz you can do that), or "straight" mode with a surround signal.
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