You are misreading my post. I wasn't saying they scale well BECAUSE they are efficient.
My point was that they need less scaling because of their efficiency. ...and I did say they scale well.
The need for a powerful headphone amp is only necessary for squeezing the last few percentage points of high quality sound out of them.
You're welcome to disagree, just my opinion.
Got it, I think.
But do you also infer that the PM-1 will scale at proportionately smaller increments than a less efficient set of headphones along a gradient of rising amp power/quality? It sounds like you are saying that there is less room for improvement with the PM-1 versus a less efficient planar.
Yes, I kind of am saying that, based only on my personal experience, which is limited since I have only heard the PM-1 with a couple of amps.
Perhaps they scale even better with an uber high end amp that I have not had the opportunity to use, but at the same time I can't imagine it would be worth the price
to spend a couple thousand dollars more over top of something like an Oppo HA-1 to squeeze out 1% more SQ.
For some people, they will spend any amount for any improvement, but I try to be more practical with my money.
Keep in mind I am not saying that they scale less as a negative, but as a positive.
In other words, they sound so good to begin with, that there's not much room for improvement.