By DarkVoice, are you referring to the 336 SE? If so, they pair well with the high impedance Sennheisers; the 6XX in particular makes a great pairing (it scales way better than the 58X Jubliee). You can also consider some Beyerdynamic cans; I personally liked the DT 1990 the most (but granted, I only tried the DT 880, DT 1990, and T1. All of them were fine-sounding, if a bit v-shaped in frequency response).
However, the DarkVoice is going to be a really poor pairing with the 4XX and K7XX; keep in mind that OTL tube amps have high output impedance and tend to lose power as impedance goes down, two things that make them not suitable for the headphones you currently own (the 4XX is going to turn into an underdriven mess and the K7XX is going to sound distorted due to its low impedance). So unless you're planning on using the 4XX and K7XX on another rig and have the vinyl rig have its own headphones I wouldn't recommend the DarkVoice.