Low vs. High impedence?

[Warhawk]

Ok, from what I can tell, most headphones are around 16 ohms.
Then you get the big cans that are like 600+.

What I'm mainly focusing on are IEMs or normal buds.
Like my sony ones are 16 ohms, while triple.fi are 32.
Someone on another forum said higher ohms = louder volumes but decreases batter life, is that true?

Also, I'm going to get the marshmallows with a gift card and noticed they only had 14 ohms, is that better or worse than 16 ohms?

 

[kevg73]

ohms just rates the electrical impedence. impedence has basically no impact on sound quality. it just means that something with higher impedence needs a stronger signal to sound good. so like headphones with like 300 ohms need an amp to sound good but a pair with low impedence (like 50 or less) sounds fine without an amp. generally higher ohms means it will be quieter at the same input level.

 

[mthrsuperior]

A not entirely accurate, but close enough, analogy is this:
Imagine electricity as a liquid in a pipe.
The higher the impedence the thicker the liquid and more energy it takes to move it.
It's more about compatibility with your source rather than sound quality.

Y'all get to slap me just once if that analogy was too silly.
:alltheeth:

 

[paulb09]

You will generally have to use a higher volume for headphones with a higher ohm rating, and a higher volume on an MP3 player should run the battery down quicker. It won't be as completely simple as that, but you will probably use up the battery a bit quicker on the 32 ohm headphones than the 16 ohm headphones.

 

[ericj]

Quote:

Originally Posted by kevg73 /img/forum/go_quote.gif ohms just rates the electrical impedence. impedence has basically no impact on sound quality. it just means that something with higher impedence needs a stronger signal to sound good. so like headphones with like 300 ohms need an amp to sound good but a pair with low impedence (like 50 or less) sounds fine without an amp. generally higher ohms means it will be quieter at the same input level.

In moving coil drivers, which is what most headphones are, a lower impedance headphone often has the coil wound with thicker wire, where the higher impedance coil is wound from a relatively long length of thinner wire.

The weight and shape of the coil probably does have some very small impact.

Take for example how premium beyers are available through the manufactur program are available with 32-ohm and 250-ohm versions of the driver -- chances are the only difference is the coil, and yet people say they sound different.

If the amp or source has a capacitor-coupled output, the impedance of the headphone interacts directly with the capacitance on the output to form a high-pass filter.

A Sennheiser DSP Pro (aka Lucas) for example comes from the factory with 100uf output capacitors. A 16-ohm headphone is rolled off 3db at 100hz and it only gets worse as the frequency gets lower - all of the audible bass is severely attenuated.

By comparison a 60-ohm headphone like any of the PortaPro-derived Kosses plugged into the same 100uf is down 3db at about 30hz - so you get all of the midbass and almost all of the audible bass.

And finally, you cannot ignore the sensitivity of the headphone, generally expressed in db/mw or db/v. A very sensitive 300-ohm headphone is actually far, far easier to drive than a 32-ohm headphone of average sensitivity.

 

[kugino]

Quote:

Originally Posted by kevg73 /img/forum/go_quote.gif ohms just rates the electrical impedence. impedence has basically no impact on sound quality. it just means that something with higher impedence needs a stronger signal to sound good. so like headphones with like 300 ohms need an amp to sound good but a pair with low impedence (like 50 or less) sounds fine without an amp. generally higher ohms means it will be quieter at the same input level.

all headphones need to be amped...headphone outputs on any device provide some amplification. it's a question of how good the amp is.