Audio Performance

I'll split the audio performance analysis into two parts—gaming and music. Even though the headset produces the same sound regardless of what it's being used for, you won't necessarily look for the same things while annihilating your virtual opponents as you will when listening to your favorite tunes.

Gaming

First and foremost, if you don't believe in headphone burn-in, the initial period of use during which they somewhat alter their sound performance, the Beyerdynamic MMX 300 2nd Gen is likely to change your mind. When I first started testing the MMX 300 2nd Gen, I didn't like what I was hearing at all. It sounded sterile, thin, and exceptionally bright, even harsh. Only after I had left the headset playing at a fairly high volume for about ten hours did its sound become more pleasant to the ears. Make no mistake, though, this is still a bright-sounding headset and as such, somewhat of an acquired taste.

It should also be noted that the Beyerdynamic MMX 300 2nd Gen isn't all that easy to drive. You won't necessarily need a dedicated headphone amplifier, but I kept cranking the volume on my on-board sound card (ASUS ROG STRIX X99 Gaming, equipped with the ALC1150 audio codec), as well as my external USB sound card ($50 Creative Sound Blaster E1), all the way up to reach a volume level I was satisfied with. Depending on the quality of your sound card (its headphone amplifier, to be exact), your mileage may vary.

Gaming performance—especially if you're into multiplayer shooters, where you need to hear and be able to accurately position everything and everyone around you—is the bread and butter of the Beyerdynamic MMX 300 Gen2. It's capable of delivering an impressive level of detail and clarity in the higher mid-range and well past 4 kHz, with impeccable stereo imaging, which means that your in-game opponents have no chance of sneaking up on you and catching you off guard. The MMX 300 2nd Gen does wonders to help you dominate in games such as CS:GO, Fortnite, PUBG and Quake Champions. The sheer amount of auditory information delivered by this headset is simply staggering.

The bass is rich and deep enough to make various in-game events, such as massive explosions and engine noises, sound exciting, but the overall brightness of the sound is likely to leave you wanting more when playing dialogue-heavy games, as well as those utilizing ambient sounds and music to build atmosphere. For games like those, a warmer-sounding headset would be nicer to listen to; the Sennheiser GSP 600 comes to mind as a good example, seeing as we're deep in the "money is no object" price range.

Since the Beyerdynamic MMX 300 2nd Gen offers a closed-back design, sound leaking in and out of the ear cups isn't an issue at all. It offers a solid level of passive noise isolation and can be used in a room with other people without issues.

Music

When it comes to listening to music, your experience with the MMX 300 2nd Gen will be highly dependent on your proficiency with bright-sounding headphones. As I'm generally looking for a warmer sound signature for my music-listening sessions, I can't say I'm in love with the way the MMX 300 2nd Gen handles itself in this area. At the same time, I can't really criticize it for that because the tuning of the built-in speaker drivers is exactly like it is supposed to be since Beyerdynamic was openly going after exceptionally informative and detailed high frequencies.

The MMX 300 2nd Gen will let you hear some of the details you most likely never heard before, such as various cymbal finesses and even the subtlest guitar notes. Depending on the genres you primarily listen to, its brightness and mid-range accuracy could prove to be enjoyable. I found it quite nice for rock and many metal genres, but much less so for electronic and piano-heavy music. Due to its sound signature, the MMX 300 2nd Gen is also very revealing. Meaning, if the quality of the song is low, bitrate or mixing/mastering-wise, it will sound outright bad. I don't doubt that this headset could be used for studio monitoring.

I didn't mention the bass, which could make you think that there isn't any, but that's not the case at all. On the contrary, the bass is punchy, deep, and well balanced without being overdone and potentially prone to spilling into the mid-range.

The MMX 300 2nd Gen definitely sounds good enough to benefit from a higher quality sound card or a dedicated DAC/headphone amplifier. If you're in the market for a $350/€300 gaming headset, it's safe to assume you don't plan to simply plug it into your on-board sound card.