Originally Posted by manbear
People can decide for themselves if a headphone with a 92.5 dB/ mw sensitivity rating and a constant, non-reactive impedance can ever take "different amounts of power to reach the same volume," in the real world, and that decision will indicate whether they understand what I'm saying or not. I've already written enough to explain my position, so it's beyond my control at this point. It seems like most people here don't really care though...
LOL @manbear, you only think that people are beating a dead horse disagreeing with you because you are misapplying a basic high school physics equation to a problem that has more variables than that. no offense intended, but you obviously do not have the background or expertise in this field to continue throwing out your opinions out as fact. people more knowledgeable about the subject than you have been trying to explain the concepts to you, but from reading the thread, you've just been either ignoring or misunderstanding their responses.
For example, the statement about "a constant non-reactive impedance" in your above post is incorrect:
Headphones impedance as specified by manufacturer is only *nominal* impedance, but actually, it varies with the frequency of the signal. Some headphones can have as much as double this value at certain frequencies. We call this value 'load impedance' , or 'Zl'
This concept was clearly articulated during that long-winded discussion earlier... In addition, other concepts such as the impact of the actual amplifier output impedance (Zs) on signal strength, primarily voltage-driven vs current-driven amps, etc were brought up and explained... your points were individually addressed and explained why the assumptions behind them were wrong...
I am certainly no expert in this field, but by simple reading this thread and a few other explanation threads, I can understand why claims you made in your discussion are simply incorrect. You are missing a lot of basic information, and you should really take the time to read the introductory post in this thread since you are so passionate about the topic: http://www.head-fi.org/t/607282/headphone-amp-impedance-questions-find-the-answers-here
Regarding your claim that output power the only measurement that you need: you can refer to this thread for further explanation: http://www.head-fi.org/t/552246/how-important-is-the-power-rating-with-headphone-amps
It is great to see that you are so interested and passionate about the subject, but please keep in mind, this is the HE400 discussion thread. Not the how do amps work thread. There are many knowledgeable people here who can further discuss that topic with you & clear up any remaining misunderstandings on one of those threads.
Edited by money4me247 - 12/31/13 at 12:55pm