I currently own two headphones Oppo PM-3 & Sony WH1000XM3. I've realized, for the PM-3s, the bass and terble are recessed and that the mids are forward. The bass and treble are neutral. The mids are slightly warm. Since the bass is neutral it sounds a little recessed to me. Maybe it really isn't recessed. It's just the lack of warmth. I am noticing that the treble can be a little harsh and there's some sibilance. This especially happens if I use an amp, FIIO Q5 with AM3A or AM5. Straight out of my phone I can hardly hear any treble. That's with my s7 and note 9. The note 9 is better than the s7. In spite of the harshness I'm preferring the sound with the amp, since I can hear the treble, but it is fatiguing. For the Sony's, the bass and treble are forward and the mids are recessed. The bass is warm. The mids and treble are neutral. Having read the glossary for the forum, I might say the Sony's are fun. The noise cancellation is great, and they'll perform well when I'm working at client sites. I like the warmth of the bass on the Sony's and the warmth of the mids on the PM-3s. Instruments sound great on the Sony's. Not so much for the vocals. Vocals sound great on the PM-3s. Why did I buy the PM-3s? The glowing reviews. Don't get me wrong. They're great headphones. I've had many instances of, "I've never heard that before!?", but I've listened to the song a hundred times before. Now that I have the Sony's and the FIIO Q5, I'm noticing the differences, and starting think I want something different. If the treble were better on the PM-3s, less harsh, I probably wouldn't be looking for another headphone. My biggest concern is the detail. I don't just want the next headphones to sound a certain way. I want to also have all the details that I've been hearing my PM-3s.