"Joseph Oberlander" asked
For what exact purpose? I mean if you're trying to build a little
headphone amplifier yourself it's a bit different than, say, buying
an A/V receiver.

Generally, though, the sad fact remains that our ears are pathetic
compared to most of the rest of the mammals out there and technology
has had no problem with exceeding its limitations in the last
20+ years.

Ok, point well taken. I want to decide wheteher my stereo system components
are up to the "competent design" standard, whatever that is. I assume there
is such a standard because it is regularly referred to on RAHE. I would
call my sysytem entry level high end, and wonder whether I should spend more
and where to spend it. I buy electronics, and either buy or bulid speakers.
Components in question? CD player, amp, preamp, interconnects, speaker
wire, and speakers. Of course I don't expect criteria for speakers.

If 20 year old components exceed my hearing then I could use the criteria
to select vintage gear, which might be a nice saving. Or I could buy an AV
receiver to use for stereo to get in lower cost bi amping. Who knows?

Wylie Williams