Joel, Bart, the 300 ohms of the Senns is a tough load for the Dragonfly. While the Dragonfly can drive them, I also have one, it does not truly do them justice.

My favorite combo for the HD6xx is either Class A solid state pairing or tubes. Tube amps that can drive the HD6xx well are especially a synergistic combo. :yes:

Joel, looking forward to your impressions with the Meze 99! :music:

Good morning. I am also an owner and fan of the HD 650s. For those who are thinking “along the lines of” iPhone/iPad >>> Dragonfly >>> HD 650s, here is an alternative you may want to try (or something along these lines). In my bedroom I have Schitt Jotunheim DAC/Amp. Sounds great, more than decent power and for what you get, just cheap!. Lightning to USB from the i-devices do not provide enough power for the USB connection to the Jot. However, Apple now makes two different Lightning to USB camera adaptors. The original doesn’t work. But now, they also have one that is powered— the “Lightning to USB 3 Camera Adaptor. For, like $39. So you plug the lightning end of the adaptor into the iPhone or iPad. The other end of the adaptor has to openings- one for USB 3 which you connect to the Jot (with a USB cable) and the other is Lightning- and that you use a lightning to AC power adaptor. It works like a charm. It is a super cheap and easy way to listen to Qobuz on good ‘phones from a iPad or iPhone. Your choice of dac/amp may vary.

I received a new headphone tube amp, the Yamamoto HA-03, an absolute killer with the Sennheisers HD650 and HD800! More to follow :music:

http://cdn.shopify.com/s/files/1/061...g?v=1641576639

I wonder where my HD-660S's fall in the equation.

The mass drop 6xx cans for like $200 are ungodly good for the money. I like it better than my HD600s and the old HD650.