[Eisenhower]

Quote:

Wrong headphone, idiot. I was talking about my SE-700. Did you even READ my post?

 
 

The K240's specifications don't give any indications that they're even remotely hard to drive, but I've been constantly told that they still need an amp. They don't seem to get much better from my E7 as opposed to my iPhone or my laptop...

 
There, I quoted the entire post because you apparently don't remember what you wrote. That looks to me like you said the K240's don't improve with the E7 versus your iphone, which contradicts your later post saying (without reference to any specific headphone), that a headphone amp improves sound and called me stupid for not knowing that. Seems to me you are a very defensive loser.
 
 
The SE-700 uses piezoelectric film drivers, which is a completely novel and thus irrelevant design since it is not at all similar to dynamic headphones like the K240's. If they were near infinite impedance, I doubt an E7 would make them loud enough to even hear. 
 
I really don't see where you get off calling me an idiot.. I actually gave you the answer before anyone else, that the E9 has a higher output impedance and is thus a worse choice than the E7 you already have.
For some reason I highly doubt you even know what output impedance is, or even read any of my posts, or anything about how amplifiers work, and would rather call me stupid because you read some audiophile nonsense online. You are exactly the problem with "audiophiles".
 
 
But go ahead, buy an E9; the ultra-audiophile grade capacitors will make the bass energy much faster and dynamic, the extra power will increase the treble range (and also the energy and transients)  

 

[IzzyAxel]

Quote:

 
The impedance is a function of frequency, may be different at different frequencies, as you say.
 
But considerations of impedance with regards to frequency are already accounted for, if you're looking at the frequency response of the headphones.  Those plots are generated with some nominal voltage level, the same for all frequencies, hopefully using an amp with minimal output impedance so the voltage into the headphones is consistent across frequency.  Anyway, you don't end up with insufficient voltage at some frequencies but not at others.  That's not how it works.
 
 
Root mean square is a statistic of a signal, the square root of the mean of the squared values.  For an AC signal, the value over time changes; rms value may be of interest to describe the tendency or shape of the signal, or more practically, for energy or power calculations.  An impedance is not a signal.  To confuse this highly implies you've never done RMS calculations, had to use it for anything.  Now you know, hopefully.

No, sorry I haven't  lol, I thought a measurement which fluctuates over a duration of some measure could have an RMS.  The more you know, etc.
 
Well, the voltage thing, idk what truly causes it if the varying impedance doesn't, but I've experienced it moving from the iPhone to the E7 or the HT Omega Claro Halo, the DT1350s in particular gain extension both ways between the first and second 2.

 

[Eisenhower]

Quote:

No, sorry I haven't  lol, I thought a measurement which fluctuates over a duration of some measure could have an RMS.  The more you know, etc.

 
You can take the RMS (root mean square) any set of numbers... It is used for signals that fluctuate between positive and negative values (e.g. AC voltage).

 

[mikeaj]

Actually I take that back.  You can calculate RMS for any set of numbers or function, as mentioned above.  It's just by far most commonly done for functions of time (need not have negative numbers though, or even change at all), usually for periodic functions.  In this context, all the RMS values are over time. If you want to calculate the RMS impedance over the audio band frequencies, then be my guest.  It just doesn't really correspond to anything that useful.

 

[takato14]

Quote:

 
The SE-700 uses piezoelectric film drivers, which is a completely novel and thus irrelevant design since it is not at all similar to dynamic headphones like the K240's. If they were near infinite impedance, I doubt an E7 would make them loud enough to even hear. 
 
I really don't see where you get off calling me an idiot.. I actually gave you the answer before anyone else, that the E9 has a higher output impedance and is thus a worse choice than the E7 you already have.
For some reason I highly doubt you even know what output impedance is, or even read any of my posts, or anything about how amplifiers work, and would rather call me stupid because you read some audiophile nonsense online. You are exactly the problem with "audiophiles".
 
 
But go ahead, buy an E9; the ultra-audiophile grade capacitors will make the bass energy much faster and dynamic, the extra power will increase the treble range (and also the energy and transients)  

I do see how the SE-700 could be irrelevant, but my Reference One is dynamic as well (with 250 ohm voice coils and spec'd at ~90dB/mW SPL) which also sounds significantly better from the E7 than the iPhone. Maybe the extra detail I think I hear is psychoacoustics getting the best of me, but the midrange is definitely worse out of the iPhone and they don't feel as lively. The iPhone gets them louder than I need but still doesn't sound as good as the E7.
 
I called you an idiot because of the generally rude attitude you took at first and the one piece of information you said that was wrong. I blow things out of proportion when it ticks me off. Its a character flaw of mine that I'm trying to get rid of. My apologies. I don't specifically know what output impedance is but I do know that I should aim for as low as possible in almost all situations. 
 
And actually, I'm just skipping the E9 and going for a Lyr instead. The E9's high output impedance won't work well with anything but the SE-700s and since I'll be getting an HE-500 sometime in the future I will need the extra power. 
 
At this point, I'm just thinking I don't like the K240s. The highs are beautiful, the mids are smooth, and the bass is airy, but they're too dull, too sleep-inducing. I guess the features of it made me really, really want to love it but I just couldn't.
 
Again, my apologies. 

 

[IzzyAxel]

Quote:

I do see how the SE-700 could be irrelevant, but my Reference One is dynamic as well (with 250 ohm voice coils and spec'd at ~90dB/mW SPL) which also sounds significantly better from the E7 than the iPhone. Maybe the extra detail I think I hear is psychoacoustics getting the best of me, but the midrange is definitely worse out of the iPhone and they don't feel as lively. The iPhone gets them louder than I need but still doesn't sound as good as the E7.

 
Then again, that change could be from moving from a terribly designed amp section on a (probably) noisy PCB to a properly designed discrete amp circuit.  And that's probably what I'm hearing too.