Amazon.com: AKG K 701 Ultra Reference Class Stereo Headphone Level 1 : Electronics
AKG Q 701 vs Sennheiser HD 650: What is the difference?
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...]
Frequency response of the AKG K701 (blue) and the Sennheiser HD650 (red). Really interesting result according to http://ift.tt/XzBtEO But don't stare at the num…
Sennheiser HD 650 vs AKG Q701 Side-by-Side Headphones Comparison - RTINGS.com
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Sennheiser HD 650 vs AKG Q701 Side-by-Side Headphones Comparison - RTINGS.com
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Amazon.com: AKG K 701 Ultra Reference Class Stereo Headphone Level 1 : Electronics
AKG Q 701 vs Sennheiser HD 650: What is the difference?