I just added a AKG K7XX from massdrop to my stable as I am lacking a good open or semi open back pair of cans and this deal was too good to pass up. I chose the K7xx over the Senn HD6xx as I didn't like the Senn HD650's when I borrowed my room-mates pair, they seemed to my ears a bit veiled and not as detailed as I would have liked. Kind of wondering what everyone else has and which they enjoyed the most. In my stable I have: AKG K550 AKG K7XX AKG M220 Audio Technica ATH-A900x Ausdom Anc7 Corsair Void Grado SR80e Grado eGrado Klipsch R6 On Ear Monster DNA Philips Fidelio L2 Sennheiser HD201 Sennheiser HD558 Sennheiser HD598 Sennheiser HD6XX V-Moda Crossfade M-100 - Audioquest Nighthawk Selling Amp and Dacs: Monoprice Hybrid Tube Amp/dac Sound Blaster X-Fi USB 5.1 Sound Blaster Omni Sound Blaster X G5 iFi micro iDSD black label Amp/dac SOLD Xduoo X-05 dac/amp SOLD After the K7XX I might put some serious consideration into a set of Planars. Edit 8/10 Just picked up a set of AudioQuest Nighthawks, will update when I get them on what I think. Edit 8/14 Finally finished auditioning my Nighthawks. The reviews were not kidding, it really is a love or hate relationship with this set. It sounds like I'm listening to music through a 1980's buick car stereo speakers. The sound is totally liquid where everything sort of blends in together with massively dark veiled sound with recessed mids and lazy bass for the most part. I have to say that I am not in love with these but at the same time intrigued. I much prefer the sound of an AKG with it's pristine scalpel precise imaging and clear sound, nighthawks are going to go up for sale. $300. Edit 9/4 Turns out I've been really enjoying the nighthawks but connected to my Galaxy S8 which makes them sound like the greatest set of cans ever vs mediocre out of my Sound Blaster X G5 dac/amp. Edit 10/11 Have new pieces of equipment. Monoprice Hybrid Tube Amp/dac and an iFi iDSD micro Black Label dac/amp. Grados are on the way. Next on my radar will be a pair of Beyerdynamics DT880 Pro/Premiums or a HiFi Man 4xx from massdrop. Monoprice 1060m Gen 3 is also temping, whenever that comes out. My Xduoo X-05 amp/dac went up for sale. Whomever has a HyperX Cloud Alpha or Revolver should let me know what they think and compare them to something more higher end they might have.