Johnathan1107 (Master Chief reference?),
I recommend the Q701 as my favorite headphone I've experienced, and because it generally is well reviewed by others too. I use mine with my Xbox 360 all the time.
Clip-on lapel mic (seems to regularly go in and out of stock, better than Microsoft Chat mic):
http://www.amazon.com/Neewer-3-5mm-Hands-Computer-Microphone/dp/B005DJOIHE/ref=zg_bs_11974771_14
Adapter to connect clip-on lapel mic to Xbox 360 controller (I have 2 of these, though the Mixamp and Recon3D USB have their own included adapters):
http://www.amazon.com/gp/product/B005543MAG/ref=oh_details_o04_s00_i00?ie=UTF8&psc=1
I haven't heard the Sennheiser PC360... FWIR it's very balanced and good, sometimes not very engaging. Take away the built-in mic and the PC360 = Sennheiser HD555. The HD55
8 is a slight uptick in quality, and still cheaper than the PC360. IMO The PC360 still isn't super convenient because you still need some additional adapters if you want to use it with a console (like those included with a Mixamp or Recon3D). The price difference is about $20 new... Not a huge deal but after mic + adapter you still have enough savings for a Steam game or pizza and dessert
Of course... I just noticed there are two refurbs for sale on amazon for just over $100... That is a pretty great deal.
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Don Tonberry,
I have a DSS now, and i just plug my mic straight into my controller (with an adapter, see above). Usually, I can mix game vs chat audio balance by turning up the volume on my DSS (all sounds louder), and turning down the game volume in the game's settings menu. I use this method all the time in the CoD games and several of my single-player games, though strangely the Halo games don't offer a volume adjustment in their settings menus. I'm not a huge fan of the Xbox's live "ducking" feature that lowers game volume temporarily if someone starts chatting, because I have a buddy who does not shut up when he's drunk and I end up not hearing tactical cues
Plus, some people just have really bad, quiet microphones, and I need to turn up the volume very loud to hear them at all, and I don't want the game to be nearly that loud.
The steelseries mixer is a passive device (no amping), so it just adds impedance to the circuit and thus degrades sound quality the further you get from 100% volume. My chat adapter has a mic-in port AND a chat-out port... I only use the mic port now (and have all chat/voice audio play through "speakers"), but possibru I could hook up a little amp (like my FiiO E5) to the chat-out port and then use a headphone y-splitter cable in the reverse direction to merge game and chat audio back into my one headphone... I could try it, I have all the pieces, but I probably won't bother, haha.