Feb 15, 2021
How does it drive the 1990 pros? Im getting some 6xx and dont think this will have the power to really use them.
Feb 16, 2021
For a 250 ohm set of headphones, the 1990 is fairly efficient so the amp does a fairly decent job with them. It's definitely able to achieve uncomfortable/damaging levels of volume, and the sound quality is pretty decent especially considering the price. The 1990 is a very resolving set of phones, so any "insufficiencies" in the amplification will be easily noticed. Like I stated in my review, it does have a warmer sound and is not as resolving as my JDS Atom amp; which is fine considering that a lot of Beyerdynamics have a tendency to be on the brighter side. I've ran both my DT880 and DT990 (both 600 ohm versions) on this amp. I can max out the volume knob with those two cans and the sound outputs are still a bit low and certainly lacking in depth, but they are 600 ohms so keep that in mind. I personally don't have any experience with an HD6xx so I can't speak with any authority, but from the reviews I've read/watched of them, this amp shouldn't have any issues driving the 300 ohms of the 6xx. The sound, however, will probably sound rather lackluster from this amp with the 6xx. Another problem may perhaps be the warm sound output of the amp, and the Sennheiser "veil". Since many report Sennheisers to be a bit lacking in the highs, the warm sound output of the amp may further exacerbate the masking of treble with the 6xx. Like I said, I don't have a 6xx so please don't take my word as truth; this is all just an educated guess. If I were asked to make a decision on a new amp purchase for a 6xx, I would personally go with the JDS atom or a Schiit Magni+ if I were in the ~$100 price range. If you're able to swing the extra cash, I would personally go with the JDS El Amp II. $250 may be quite a swing from the $50 of this amp, but if you're going for the quality of sound that the 6xx is known for, I would highly recommend it. You should check out DMS's review of the JDS El Amp on Youtube. I hope this helps at least a little.