OK, to compare square waves, we first need to normalize them. From experience, small differences in volume make no difference in impulse response or square waves. (The only times where I've seen differences in square waves and impulse response decay was with high Zout devices on lowish Zin headphones. An example would be the Meridian Exploder USB DAC gizmo into the HE-500.) So I will take the liberty of normalizing the graphs. The HD700 graph needed to be expanded by 15% on the vertical axis to be comparable to the HD650. Looking at purely graphs, it's I don't think one can say that one headphone's square waves is much better to the other. This is what we can discern: The HD650 has marginally more overshoot. If we try to guesstimate the HD650 cycles (looks like about seven per half wave), then we can probably expect some ringing in the upper mids / lower treble. The HD650 ringing is about half the duration of the HD700s ringing. In fact, the HD700 ringing doesn't really stop. It sort of goes on and on. The HD700 has less overshoot; but guesstimmating the cycles, it looks like there is ringing in the lower / mid treble region. Continued ringing is very horrible. If I'd have to pick an audio transformer (it's typical to measure 10kHz square waves on transformers), the one on the right goes into the garbage immediately. Since nothing is perfect, there can always been overshoot or undershoot. For headphones and transducers, subjectively, I prefer an overshoot instead of undershoot; but continued ringing under all circumstances is bad. The only things we can say here is that the energy dissipation with the HD650 is lower in frequency than the HD700, with more initial overshoots, but less duration. In the end, the better visualizations to look at are the CSDs and frequency response. Anything else subjective people are deriving from the square waves is coincidental. Unfortunately, I do not have CSDs for the HD700 on my most current V2 measurement rig. In terms of clarity, I strongly suspect the HD700 has much better distortion figures than the HD650, especially in the bass. I don't have distortion numbers for the HD700, nor do I care. If one can pay $600 for an HD700, much better to stretch that to $1000 and buy a grey market or used HD800. There is a reason why the HD700 started at $1000, went down to $700, are are now at $528 clearance special on Amazon.