I purchased a set of these from Headroom about a week ago. They are truely wonderful phones, and I can't recommend them enough. More details in the near future.
Being a long time audio enthusiast and packrat, I have various integrated amps and power amps laying around to try with the K1000s. Lower power seems to be better. You need the voltage, but not the current. The adapter that comes with the phones is a 4 pin XLR to tinned lead cable that is intended to connect directly to the speaker terminals of an amplifier.
Driving the phones off the amplifier outputs, per AKGs recommendations I was astounded at the articulation and resolution! IMHO my HD-600s do not even come close. What I did not like was the relatively high level in the upper frequency range, and some bass rolloff. Tollerable, and expected since these phones are not equalized, but a bit tiring to me. I noticed that I was only using 100 mW or less for most listening (ratioed 8/120 times the 1W peaks on my power meters). Since the impedence is 120 ohms, I decided to try running them off a headphone output. I was using an old Yamaha integrated amp at the time. Wow! The tilt in the response curve almost went away. I soldered on a 1/4" phone plug and have been listening to them that way since. I am now looking for an amp designed for the high impedence that can output around 1W (the rated power handling). I also tried driving them with an Airhead amp. Fine at low levels, but it could not push quite hard enough.
The amount of umph that the K1000s need also depends on how you wear them. Swing them way out, and you will need more power. I like them in closer, and I don't listen at very high levels.
I spoke with Todd yesterday about the amp issue. Headroom is working on something, so stay tuned.
Right now I am considering the Grado amp. The X-can has the power that I need, but I don't like the idea of the bass rolling off. The K1000s already roll below 50 hz at around 12db/octave, based on the published response curve. That also seems to vary greatly with placement.
My advice: grab a set of these headspeakers and worry about the amp later. They are a pleasure to listen to.
btw, isn't K1000 redundant?
