DSP is inevitable, and I welcome its eventual arrival. Contrary to what the people blowing multiple thousands on each new flagship might say to justify their purchase, there are no massive gains to be had with passive drivers anymore. The same basic issues--spikes in the lower treble, lack of absolute bass extension in open dynamic designs, raggedness in treble response and a wide peak around 1 kHz in planar and electrostatic designs, the incorrect placement of the presence hump at ~2.5 kHz instead of 3.5 kHz in IEMs, the strong 5 kHz spike also in IEMs, and on and on--these same issues keep coming up over and over and over again in every new product. At this point, we have to accept that, without active correction, passive designs will always have at least some of these issues. Why spend exorbitant amounts of money and effort playing whack-a-mole trying to engineer a solution to one of these things, maybe not even completely alleviating the issue or else introducing another issue while solving the first, when you can take a driver with workable frequency response and good time domain characteristics (i.e. no ringing) and actively correct the FR. What's more, you can even measure the system (i.e. the headphone while it's on the individual listener's ear) and, in real time, generate precise corrections to hit any target curve. Want a different sound, or a closer approximation of neutral as further research refines the target curve? Just recalibrate for a different curve. The beauty of all this is that, since the mainstream industry is already moving toward wireless headphones, you're already building an amp and some IC into the cups, anyway, so how much extra effort would it be to fit in a DSP solution on the PCB and cobble together an app to program it? The effort, of course, would be in designing the calibration system, choosing a curve, etc. But my point is it would fit in the cups alongside the stuff you're already putting in them to power the headphone.