I have a 15 inch Macbook pro 2018 with i7 8850H + Radeon 560x Pro, and I can't believe how great it sounds with my HD650. I used to have a Schiit Stack (magni2 + modi2), and I never liked the sound of HD650 from this setup. The schiit seems to boost the punches of bass a bit too hard for my taste, which sort of destroyed the smoothness of HD650 and coherence. Have that being said, however, the Schiit Stack does give my Q701 enough power to shine its treble and sub-bass. I also have made some eq files for my HD700 to make it sound more like HD650/600, and HD700 also definitely benefit from the schiit stack as well. The Macbook pro keeps the source coherent and transparent, and paring it with HD650 just makes the musics beautiful and elegant. In such setup, the HD650 has a transparent and balanced frequency response that doesn't sound dark like what people used to associate HD650 with. Actually I was going to sell my HD650 for something like HD600 as I really don't like the extra upper bass bump that blends into the mids which makes the over all sound signature more dark and muffled, despite I don't think the treble on my later version of HD650 is lacking much. After paring it with MBP, I think the treble is actually airy and melodic without fatigues found on AKGs, and the sub-bass is now better controlled as well. I don't know if it is the sound the Sennheiser engineers intended to make on HD650 originally, but I think it definitely lives to "Reference Headphone" title on the HD650 packaging box. The sound is clean as well, which I guess Apple probably did some good job at shielding the motherboard.