I tired these for a while as a friend owns them. I have the Game Zeros and I actually like those a bit better than these. These game ones sound closest to my HD555's for gaming. They have a fairly flat and neutral sound with a decent little bass hump that makes explosions sound good in games. Being open back they inherently have a good sound stage and are pretty decent at placing enemies. They however sound a little bit veiled. Everything sounds pretty flat and nothing really pops out at you. All the details are there but you have to hunt for them a little bit. That does tend to make you turn them up a little more than other headsets. Could be a good thing or a bad thing. They have the normal smooth pleasing, non fatiguing veiled Sennheiser sound. Not to say there is anything wrong with that. They sound great for music as well and I can't say that for the Game Zero's. They pair fine with just about any surround sound software. The Razer and Creative SBX studio both sound pretty decent on these. I might actually prefer the Creative for these as it makes the details pop a little bit more than the Razer software due to the mid boost that the creative software applies.
This is a Copy paste from my Game One review for the mic as they have the exact same mic:
Now on to the mic... The mic on these sounds great... If your sound card can power it up. This mic with my Creative Sound Blaster Z might have been the absolute worst mic and sound card pairing I have ever heard. In fact once I got these my 2 year old SBZ got ripped out of my PC and thrown in a box. I have a Schiit stack now so it was time for it to go anyways as I was just using it for mic in. After researching I found that headsets all use small condenser mics that need power. Sort of like regular condenser mics that require phantom power but on a lesser scale. Usually headsets run on 'line power" between 2 and 9 volts. PC sound cards put out voltage to mics usually in the range of 2-5 volts. Most gaming headsets with tiny microphones are perfectly happy getting 2v and sound fine... However the mic on the Gzeros is a bit bigger and is pretty quiet with 2v going into it. More voltage = more sensitivity with condenser mics. Creative cards appear to only put out about 2V. With my Creative Sound Blaster Z I had to max the mic volume and mic boost to get enough volume from this mic which resulted in tons of white noise. Asus sound cards tend to put out a little more voltage to mics (Around 3V) so I would pick that over a Creative card if you are considering these headphones. I would also steer clear if you have Realtek onboard audio as all the Realtek chipsets I have tested put out about 2.2V. There are a few chipsets out there that put out 4.5V and I would assume that would be ideal for the Gzeros or G1's for that matter. Still trying to find a small USB sound card to use for mic input only that puts out 4.5V to use with the mic on these. So far I haven't been able to confirm voltage for anything other than the ones I have personally tested because that information isn't published by sound card manufacturers.
This is a Copy paste from my Game One review for the mic as they have the exact same mic:
Now on to the mic... The mic on these sounds great... If your sound card can power it up. This mic with my Creative Sound Blaster Z might have been the absolute worst mic and sound card pairing I have ever heard. In fact once I got these my 2 year old SBZ got ripped out of my PC and thrown in a box. I have a Schiit stack now so it was time for it to go anyways as I was just using it for mic in. After researching I found that headsets all use small condenser mics that need power. Sort of like regular condenser mics that require phantom power but on a lesser scale. Usually headsets run on 'line power" between 2 and 9 volts. PC sound cards put out voltage to mics usually in the range of 2-5 volts. Most gaming headsets with tiny microphones are perfectly happy getting 2v and sound fine... However the mic on the Gzeros is a bit bigger and is pretty quiet with 2v going into it. More voltage = more sensitivity with condenser mics. Creative cards appear to only put out about 2V. With my Creative Sound Blaster Z I had to max the mic volume and mic boost to get enough volume from this mic which resulted in tons of white noise. Asus sound cards tend to put out a little more voltage to mics (Around 3V) so I would pick that over a Creative card if you are considering these headphones. I would also steer clear if you have Realtek onboard audio as all the Realtek chipsets I have tested put out about 2.2V. There are a few chipsets out there that put out 4.5V and I would assume that would be ideal for the Gzeros or G1's for that matter. Still trying to find a small USB sound card to use for mic input only that puts out 4.5V to use with the mic on these. So far I haven't been able to confirm voltage for anything other than the ones I have personally tested because that information isn't published by sound card manufacturers.
I know a lot of the experienced audiophile types here will probably dismiss these and recommend that you just save some money and buy a headset and attach a modmic, but I think they strike the perfect balance in what a gamer/music lover would want. You're basically getting a 558 with a really good mic. I know it costs more than the other route, but to be honest, the mic is fantastic and I love that you can mute it quickly in game just by swinging it up. The dedicated volume control on the right ear cup is also very convenient. Those last 2 features are worth the extra money for me.
If you're primary concern is positional audio for shooters, then I would recommend pairing it with a decent sound card that has a built in headphone amp. I use the base model Soundblaster Z. Using the SBX Pro Studio options in the software you can tweak the surround settings to get excellent positional accuracy. I came from the Astro A40 PC analog headset to these(didn't buy the mixamp because I use my sound card), and the difference is literally night and day. I can tell exactly where enemies are at on the map and this headset has the precision to differentiate whether they are in the same room or behind a wall due to the distinctness of the sound. I am also picking up things with these that were lost on the Astros. The highs and mids are much more pronounced and I can notice little things like fans when walking by industrial equipment on the map that the Astros for the most part just drowned out. As far as saying they don't have much depth in sound in the review above, I found the opposite to be true. I'm guessing your referring to the lack of bass, which is really not what you should prioritize in a gaming headset in my opinion. The sound stage on these is very good and is only enhanced by not pushing for an over emphasis on bass. If you want more bass, most sound cards have a bass boost gain to help with this, but you still won't get the boom of the cheaper gaming headsets because that seems to be what they go for over clarity.
For music, you can just turn off the SBX option and the additional sound processing to get a more pure audio representation(sounds bad if you don't turn this off). Listening to music on these is a joy. I switched back to my old headset to see how much of a difference it would make and I was floored by how much better the Sennheisers are. I'm sure there are better headphones you could spend your money on if you are only concerned about music/movies, but these are still excellent despite them being marketed as a gaming-centric headset. Best of both worlds for me.
Don't dismiss the sound quality of these just because they have a mic attached. They are really quite good and probably the best dual purpose...