Overall, the DT 990 Pro is an excellent choice if you're looking for a pair of mixing headphones to balance your high end and be more aware of sibilance. It's not the best for tracking as its open back so it's better as a supplementary pair than your main pair.

https://www.headphonecheck.com/test/beyerdynamic-dt-990-pro/

Good bang, mixing-grade and great sound at 180 euros MSRP. I'll give 4 out 5 stars simply because of the fact that it surely needs a proper amp to be used in its full potential. You'll have to spend a bit more buck to get the full bang, but the DT990 Pro will make it worth the extra investment.

The Beyerdynamic DT 990 Pro headphones are easily affordable and highly suitable for mixing. They are one of the best studio headphones on the market.

We're totally sold on the Beyerdynamic DT 990 PROs. These things have a great sound, excellent sound quality, are very comfortable, and have a long cord. The giant, open-backed cups give a very immersive soundstage. We also think they look good as well. If you're looking for at-home headphones, the DT 990 PROs are a great option. We highly recommend these.

The ‘Premium’ version brings improvements to the original model, delivering across the board with good sound, comfort and build

For less than $200, it's not hard to understand why the DT 990 PRO is considered to be a classic pair of cans for audio producers and music lovers alike. If you don't want to splurge on Beyerdynamic's updated line of DT PRO X headsets, then this is an absolute steal.

Unfortunately, without EQ, the DT 990 Pro’s are a tough listen. The bass and mids have good resolution and a generally agreeable tonality, but the treble really is piercing. It is not because the DT 990 are bright, as there are headphones like the HiFiMan Sundara that lean towards bright but are quite smooth in the highs. It is because they are excessively bright in spots that can quickly become fatiguing to listen to.

There’s no denying that the DT 990 PRO does have a very Beyer-like character, but that’s no bad thing, especially if exceptional spaciousness and detailed tonal depth is what you’re after. While we wouldn’t really recommend these for tracking or casual listening, we’d definitely consider them for mixing duties, which after all is their primary intended purpose. They’re not quite as flat as we’d like in terms of response, but they’ll get the job done reliably, as long as you have the means to drive them sufficiently and that you’re aware of that mild high-end boost and slight de-emphasis in the sub range.

The Beyerdynamic DT 990 Pro are excellent neutral listing headphones. They reproduce a lot of detail in high-resolution tracks and have a clear and crisp sound quality with a spacious soundstage. They may sound a bit sharp at times, as the treble range is slightly too emphasized, but bass, instruments, and vocals are well-balanced and reproduced with high-fidelity.