[WaiY]

Hi
 
I'm totally new to the hifi world so forgive me if I ask very basic questions and my ignorance.
 
I've looked up the definition of impedance within the context of earphones and headphones. Am I right in saying that, basically the lower the impedance the less output from, say, portable players like ipod, that is needed to produce a higher volume on e.g. an IEM? Conversely would it mean that IEMs with higher impedance will sound quieter due to a relative lack of power from the player?
 
If that's the case, does it mean I'd need to increase the volume setting on higher impedance IEMs (e.g. Shure 535, over 30ohms) to get the same volume as lower impedance IEMs (e.g. Sennheiser IE8 at 16ohms)?
 
I have a pair of Sennheiser IE8s but for me it's too bassy even at the lowest setting and I don't want unnatural sound by messing with the EQ setting on my ipod. I was thinking of getting the Shure 535s or Westone 3s both of which have higher impedance and have a flatter more neutral sound compared to the IE8s.
 
I've read reviews on both the 535s and W3s I think I really like the sound of them (no pun intended!). I got this idea that as with headphones (which have higher impedance than IEMs), the 535s and W3 should have a much bigger soundstage than the IE8s. Am I right? If so I'd definitely want a pair of either.
 
On another matter, can someone explain to me what specs indicate good quality IEMs, I've no idea when looking at Sensitivity (loudness?)and Frequency response (the bigger the range, the bigger the soundstage?) etc.
 
Also, if you compare only the following specs (subjectivity aside) of the W3s and the 535s  would it indicate that one or the has better sound, if not then what's your comments?
 
Westone 3                                                                    Shure 535
Sensitivity: 107 dB SPL/mW                                       119
Frequency response: 20 Hz -18 kHz                          18Hz-19kHz
Impedance: 30 ohms                                                    36
 
Please advise.
 
Thank you

 

[WaiY]

Another question...
 
Do Triple Drivers in W3s and 535s help an IEM to sound much better (however defined) than e.g. what the Sennheiser IE8s have?

 

[Iniamyen]

Impedance is an "AC-resistance" (audio is an AC signal.) In the most basic terms, if you have a voltage across a resistance, you get current flowing, and you dissipate power in the resistive load.
 
Headphone sensitivities are what count for "loudness," they tell you how loud a headphone will be for a certain power level. So a lower-impedance headphone won't necessarily be easier to drive to an equivalent level. You need both sensitivity and impedance to get a handle on that.
 
You can get an impression of how a headphone will sound from a frequency response graph but there are many other variables to take into account and it's probably a better idea to try it out yourself before making a decision based on a FR graph. If you are focused on bass response, looking for the headphones with reduced low frequency responses (relative to the higher frequencies) would be a good starting point.
 
Edit: The idea behind multiple drivers is that it's easier to get the overall FR that is desired by using more drivers. I think this is a valid theory (see speaker crossovers.) However, whether it results in a FR that is unattainable by less drivers could be debatable.

 

[brconner]

You actually want an increased low frequency response relative to higher frequencies for a increased bass response.
 
Also impedance and sensitivity will not tell you the sound quality of a headphone. More drivers doesn't mean better sound, its possible, but doesn't mean its better. More drivers means more crossovers which means its overall a lot more complicated to design.
 
Certain tonal qualities are actually pretty specific to certain frequency ranges. Check out this glossary of terms and you can get a better idea of how to interpret some things in a frequency response graph.
 
http://www.head-fi.org/forum/thread/220770/describing-sound-a-glossary
 
Here's another great site that shows how different frequencies affect sound.
 
http://www.independentrecording.net/irn/resources/freqchart/main_display.htm
 
 

 

[Iniamyen]

From what I read it sounds like he wants reduced bass.
 
Quote:

You actually want an increased low frequency response relative to higher frequencies for a increased bass response.
 
Also impedance and sensitivity will not tell you the sound quality of a headphone. More drivers doesn't mean better sound, its possible, but doesn't mean its better. More drivers means more crossovers which means its overall a lot more complicated to design.
 
Certain tonal qualities are actually pretty specific to certain frequency ranges. Check out this glossary of terms and you can get a better idea of how to interpret some things in a frequency response graph.
 
http://www.head-fi.org/forum/thread/220770/describing-sound-a-glossary
 
Here's another great site that shows how different frequencies affect sound.
 
http://www.independentrecording.net/irn/resources/freqchart/main_display.htm
 
 

 

[xnor]

Quote:

I've read reviews on both the 535s and W3s I think I really like the sound of them (no pun intended!). I got this idea that as with headphones (which have higher impedance than IEMs), the 535s and W3 should have a much bigger soundstage than the IE8s. Am I right? If so I'd definitely want a pair of either.
 
On another matter, can someone explain to me what specs indicate good quality IEMs, I've no idea when looking at Sensitivity (loudness?)and Frequency response (the bigger the range, the bigger the soundstage?) etc.

I think that the soundstage will get a lot wider with more neutral headphones/IEMs.
One possible explanation is that usually the lower frequencies in a recording are much less separated (L-R) than the rest of the spectrum. Because the IE8's definitely make the lower end 'stick out', soundstage and stereo imaging suffers.
 
edit: some 'graph' info (relative dB difference in the frequency response between 500 Hz and 100 Hz)
IE8: about +9 dB
SE535: about +3 dB .. so a lot less hyped bass