As for how much the soundcard improves the sound quality? Again, "a little" seems most appropriate. While it's great you don't need software installed to use the soundcard, that also means you're unable to tweak the sound profile to your heart's content like you can with other USB headsets.
The result is that using the HyperX Cloud II's soundcard is more like a lateral move than a real improvement. Both the bass and the lower end of the mids have been boosted a bit from the original HyperX Cloud, while the highs are a bit less clear. Testing with music, especially, I noticed cymbal crashes getting lost in the mix--a clear sign that the highs are being scraped off the top.
As I said, it's not necessarily worse than the original HyperX Cloud's sound. I just don't know that I'd call it better either. It's a more games-oriented profile, whereas the original Cloud had a more rounded, jack-of-all-trades sound.
The 7.1 is, like most headsets, disappointing. I feel like I say this in every review of a 7.1 headset (probably because I do), but no headset is going to achieve proper surround sound. At best, you're getting an awkward simulation of it. Worse, the 7.1 introduces some static to the audio that's unnoticeable in loud situations but--to me at least--somewhat distracting in quiet, reflective moments.
I honestly think the original HyperX Cloud with its stereo drivers did a perfectly fine job of simulating the sort of depth and positional tracking you'd want from a surround headset--without being a surround headset. The 7.1 here is a marginal improvement, in games that support it. It's not why you'd buy the Cloud II though.
What should make you buy the Cloud II is the fact that the soundcard also improves the microphone. The Cloud II uses the same weird detachable microphone as the original Cloud (complete with that stupid rubber piece over the jack that you'll inevitably lose as soon as you remove it). Last year I complained that the Cloud's microphone was a piece of junk, thanks to a ton of problems with plosives and noise pickup.
The Cloud II's microphone isn't perfect, but it's complemented by noise and echo cancellation built into the soundcard. Comparing mic recordings I made last year with some from the Cloud II, the difference is immediately apparent. The Cloud II microphone sounds like an entirely different (better) piece of hardware.
Should you buy the HyperX Cloud II instead of the Cloud? I don't know, to be honest. This is a pretty marginal improvement over last year--and at a slightly higher price. They're both fantastic budget headsets though, so it's really down to personal preference. Do an improved microphone and inline controls justify the higher cost for you?
Either way, I feel comfortable recommending the HyperX Cloud series as the best sub-$100 headset you can buy, with audio that easily compares to some higher-priced offerings by SteelSeries and Astro.
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