First thing apologize for poor english, i'm from italy:)
I'd wish to ask for some help, i'm currently searching for a solution to my problem: volume at late night I usually watch movies or play games 'till late and my wife doesn't like the chaos i make, but you know playing with low volume is just unacceptable I currently own a xbox360, an htpc (both connected to a yamaha ampli via hdmi) and a gaming pc. Both the pc use internal mobo audio (but the htpc streams dts or ac3 mkv to the ampli so i think no big deal), and with the gaming pc i use a cheap behringer hpx2000, i'd now wish to find a good compromise to get 5.1 with headphones (virtualised DH, not true 5.1 headsets). I saw that with a tritton ax720 i should be fine, i can connect it to xbox and pc via usb, but i'm bit worried about the headset quality and the fact that everyone seems to report background noise (to various degrees), otherwise i can go for a xonar + cal (found them a 50€ in offer) for the gaming rig but this won't resolve the x360 and htpc problem... i saw the astro a40 too but seems like that only the mixamp is worth the price, not the headset.
So i should go for the ax720? Are they really worth 140€ (price in italy), am i missing some other solutions??
Again sorry for my grammar and thanks for reading 'till here:)
First, you say all your devices are connected to a Yamaha Ampli. Which model is it? You might want to find out if your integrated amp/receiver has Yamaha's Silent Cinema feature, as this is a pretty decent virtual surround for headphones. On my Yamaha RX-V367, which was a low-price beginner model from 3 years ago, I have Silent Cinema as long as I turn on a DSP mode like Action Game and plug in my headphones. This may be the simplest connection for you at night, and you already paid for it. It would work for both of the computers and Xbox connected by HDMI. I enjoyed the effect the 1 time I got to use it, and I look forward to setting up my Yamaha receiver perminantly.
If your gaming PC is not connected to the Yamaha, your best option is an internal Gaming sound card from Creative (Sound Blaster X-Fi) or Asus (Xonar), as they create virtual 3D sound (that potentially works better than Dolby Headphone because it is not limited to Dolby 5.1 or 7.1 directions) and unlock special environment effects sounds for extra realism. NamelessPFG has a pc gaming guide here on head-Fi you should check out.
If you want to upgrade your headphones from the Behringers, the CAL! (Creative Aurvana Live!) is recommended instead of the Astro A40 or Mad Catz Tritton ax720 for the price.
I hope you understood my post (I try to write clearly), and that this helps you. Also, welcome to Head-Fi, sorry about your wallet!