I have been thinking again to this fact also because of the conversation in my thread, where I have just named you.
So, to understand all well, I take the example of the K553.
I read the have:
Sensitivity: 114 dB SPL/V
Max. Input Power: 200 mW
Rated Impedance: 32 Ohms
So, how do we read these values? And what should we read on the specs of a BT receiver in order to chose the right one?
I am re-reading your answers, but you use terms I do not know.
Like when you say "they are 38 Ohms and their sensitivity 89 dbSPL at 1 mW which reaches 119 dbSPL at 1W RMS, which is good headroom" which is like hyerogliphics to me.
I have tried to document myself with http://en.wikipedia.org/wiki/Root_mean_square and with http://blog.prosig.com/2008/04/14/what-is-db-noise-floor-dynamic-range/ but they have the tendency to explain things like for who already knows them. So that, who does not know them, will never understand them.
Specially wiki, 2km of bla bla and they never explained what this rms really is, practically, in the daily life, for example, in your sentence above.
I have understood that "headroom" is the space between the max which the headphone can take without clipping and the max it can take without being damaged, or something like that.
But I am not sure of how I should use this in the practical way.
I understand that 1 mW is one micro Watt, and 1W is one Watt, but, what is 1 W RMS???
Now, Sensitivity, ok, 114 decibel sound pressur level. this /v means? On the second link I read "dBV Voltage measurement relative to 1V – regardless of impedance."
Cool. I have no idea of what that should mean.
Max imput power. What do they mean with max? That a higher one would kill the headphone? Or that it is just useless? Anyway, 200mW, so, we need a 100mW channel amp, right?
Impedence 32 Ohms. Ok, normal. Besides, if the Impedence is not important because the only important thing is the power of the amp, why do they even bother writing about the impedence.
What is the difference between two headphones, both with max imput power 200mW, but one 32 and one 600ohm?
Or should BoTh values be matched?
I mean, should we choose an amp which says 100mW channel und 16ohm channel?
Some of your answers confused me because you said the impedence is not important of whatever.