I just re-purchased the DT 1990 because I missed mine after selling the one that I had bought just a year ago. I’m enjoying the new one for many of the same reasons as the old, but oddly I found the treble less aggressive than before. On the original, I found EQ necessary not just to achieve my preferred tonal balance, but also because the treble actually became physically painful after listening for a while. My new DT 1990 sounds tonally similar, but I’ve noticed no discomfort even without EQ.
This reminds me of something that’s long puzzled me about the DT 1990, which is that some reviewers find the treble sharp and uncomfortable, while others find it just right and more neutral sounding than their own measurements would suggest. Could that be because of unit to unit variation?
Here is a comparison of the frequency response of my old vs new DT 1990 on my MiniDSP E.A.R.S… I took several measurements on both sides and the shown curves are quite representative.
The measurements show that the new sample still has the elevated treble, but about 3-5 dB lower in level. It also has less of a dip around 4 KHz.
Then there’s the CSD. First old (notice the ridges at 8 KHz, 11 KHz and 15 KHz)
Then the new (notice the ridges from 8 KHz and up are gone)
Measurements don’t always tell the whole story, but in this case it’s interesting that my ears noticed less discomfort on the new unit and that the measurements show a less aggressive and possibly better damped treble.
Very curious …