Pros: Very high impedance & high sensitivity, built to last, reasonable detail
Cons: Lots of midrange, no bass and only a bit of treble, pretty much like most 60s headphones, awful cable
I don't usually do hands-on reviews, but in this case I'm quite certain. I got my pair of HD414 for a bargain price, still in EX/VG condition, only a bit dirty on the inside.
What originally caught my attention was 2000 Ohm impedance. I was like...really?!? Apparently someone caught up to the idea of high voltage/low current, which was perfect for me. At 2kOhm and 102dB/mW this looks like the perfect set of cans to be driven from virtually anything, even line outs!
Unfortunately while this looks great on paper, the light-speed fast transients that could result from such high impedance are not there.
Sound is vastly oriented around mid range, with no bass and only bits of treble. Kinda reminds me of Koss Pro4AAT. Non existent soundstage and highly attenuated detail.
As for comfort, my experience could be a bit biased as the pads are quite worn off, but HD414 are by far the least comfortable cans I tried.
But there is still hope.
I'm quite certain this veiled, uninteresting, degraded sound signature is the symptom of that headphone cable. Honestly I didn't see anything that'd measure worse than this.
Almost 12Ohm resistance over 2.5m, 180pF capacitance between all three wires, straight (not twisted) pairs and no isolation. This has to be the worst cable I've ever seen and is bound to negatively impact sound.
Once new cable is built, I'll update the rating to reflect the change.
After applying 4mm of soft foam onto the worn off pads, the good sound finally started to shine through. Treble started to appear, and surprisingly (or not), very clean.