Archimago's Musings: MEASUREMENTS: Sennheiser HD650 (~2010-2012) and HD800 (~2010). A comparison of two "Reference Class" headphones, and a look/listen to the "Sennheiser veil / darkness". [Inexpensive 2TB SSD and inflation in consumer electronics...]
Sennheiser's HD650s: Classic headphones bundled with Groove DAC...why? - The Audiophile Man
🔶 Sennheiser HD650 - [Official] Open Back - HifiGuides Forums
Buy Sennheiser HD 650 from £229.00 (Today) – Best Deals on idealo.co.uk
The excellent Sennheiser HD650 are down to an equally good price from Scan Computers | Eurogamer.net