If you love classical music and opera, go with AKG's flagship K812. HD800 may have more bass but cannot hold a wick to K812's lifelike details and clarity. K812 gives you front row seats in a concert (great for chamber music!), while HD800 puts you in Row P-W. I personally prefer the closer soundstage, and have owned AKG's for 30+ years of happy classical music listening. The K812 just puts a smile on my face every time. I plan to audition the Sony Z1R soon and will post my impressions. I need a closed-back can for the bedroom.