Highs: Beats > Sennheiser.High frequencies are good in both headphones, but Sennheiser has them more emphasized. Sometimes it feels like if you crank them slightly higher you're gona hear sibilants. It's on the edge and this is not the most pleasant edge to me. However, the sound is accurate and somewhat distinctive in the upper-frequency range for the Sennheiser. As for the Beats, highs are as detailed as on the Sennheiser (if not more) but not overemphasized.Mids: Beats > Sennheiser.Sennheisers have a so-called v-shaped sound profile so it feels like Beats have way more mids. It might be even too much at first, but you get used to it. Beats are more detailed and fast. Sennheiser feels muddy in comparison (but still very precise and detailed compared to Sony and Bose). I think it's partially because of overemphasized bass that brings distortion into the mid range. You start hearing things that were not originally intended to be there by artists. Because of this, Sennheiser sounds more "musical", it fills the voids between the instruments and produces an overall "dense" sound. And the Beats have more reference sound. For many instrumental tracks (rock, metal) Beats might sound boring and hollow. I can't blame the headphones because such music is usually mastered to sound good on consumer electronics. And you can't put good "dense" sound into an average stereo system. It will sound too muddy and.. just bad. So they leave the voids between the instruments and try to separate them. But on a reference headphone, this sounds... well... too reference :)Electronic music is a completely different story, this is where Beats shine! Electronic sounds are way more precise. And with Beats, you get this precision (especially in the complicated EDM tracks; I mostly listened to psytrance, psychill, idm, etc. But an average techno/trance sounds good as well). Sennheisers sound fine too, but only until you compare them with Beats.Bass: Sennheiser > Beats.The Beats are precise, again, and so is the bass. If the bass was intended in the music that you listen to - you will hear it. And you will hear exactly as much as it was planned by an artist. Rap songs sound great because of that, as well as some EDM tracks with massive sub-bass. As for the Sennheisers, well, they are v-shaped still so they add a subtle amount of bass to the overall mix, and in most cases, this sounds fine and even fun. It also comes without surprise that in bass-heavy rap songs, it starts to sound too overemphasized. In terms of precision, Sennheisers are not as precise but still hold their ground well against sony/bose/etc.Soundstage: Sennheiser > Beats.Soundstage feels subtly more open on the Sennheisers. Probably this is because they are not as precise and produce more "parasite" harmonics that make instruments sound further from your head. I like this effect but this makes me wonder if it's possible to achieve a good soundstage for closed headphones without compromising the sound speed and precision.ANC/Transparency: Beats > Sennheiser.Beats are slightly better in noise cancellation and noticeably better in transparency mode. Not as good as AirPods Max, but kinda close. Sennheiser is not bad though, it's just not as good. Wind can be a problem for both headphones, but I don't care. Beats are better at blocking fan noise but may overemphasize it in the transparency mode.Mic: Sennheiser >> Beats.Sennheiser microphones are superior both in terms of volume and quality. Beats is really mediocre, on the edge of what I would call "usable" for the zoom meetings. On top of that Beats mic sounds really quiet in Windows 11 rendering itself useless. I hope new firmware/drivers will fix that.Ergonomics: Sennheiser > Beats.I like Sennheiser more. Beats have smaller earcups with stiffer ear cushions. Also, the clamping force on my average-sized head is obnoxiously strong. Not to the point when I feel a headache after wearing them for a few hours but still too much in my opinion. However, I like the fact that Beats are more compact. It makes a difference when I listen to them in bed, for example. They don't rub as much against the pillow and don't produce a lot of noise like Sennheisers.Sennheiser ear cups are rotating 180 degrees when on the Beats, they barely move. This is important if you want to move one headphone back to open your ear when you need to listen to somebody or something from the outside world quickly. Or if you're a DJ and need to hear monitors with one of your ears :). Sennheiser earcups pivot and stay perfectly adjacent to your head, unlike the Beats.Connectivity: Beats > Sennheiser.Both headphones are ok when you're near the source, but the Beats stay connected longer as I walk away from it. The usable distance is like ~30% longer. They also perform better for a source behind a wire mesh or a security door. I know that Sennheiser is capable of working with 2 devices simultaneously and this works pretty well. Not sure about the Beats but I don't really care...Controls: Beats >> Sennheiser.Beats are very basic. They don't even have a head detection. And this feels soo good after the glitchy Sennheisers! You can read more details in other Sennheiser reviews, but they are really bad in that aspect. I bit the bullet and used them as my daily drivers, and oh boy... settings were getting changed randomly, I had tons of fantom head detection events, and when I wanted to put them on or off I almost always accidentally touched the right earcup sensor and triggered something (usually play/pause).