[carb0n67]

Can someone briefly explain to me the difference in ohmic values and how they affect headphones? Thinking about buying some dt 770's, and trying to understand the difference between the 80 ohm vs 250 ohms. 

 

[KG Jag]

Very simply--Ohms = resistance.  The higher the number, the harder they are to drive.
 
If you’re looking for headphones to use with a portable player or laptop, stick to the range of 16 – 32 Ohms with a sensitivity (efficiency) rating of at least 100 dB/mW. There are some higher impedance headphones, up to 80 Ohms or so, that are efficient enough to work well with at least some portable gear—especially if you don’t like it very loud. But, in general, the lower the impedance the better the match with battery powered devices.

 

[carb0n67]

Thanks for the reply. Have you any experience with headphones with 80 ohm resistors? As I said I'm looking into the 770's and the most common ones I see are the 80 ohms, and am wondering if they'll be loud enough without an amp to drown out say background noise in a cafe. 

 

[KG Jag]

  Thanks for the reply. Have you any experience with headphones with 80 ohm resistors? As I said I'm looking into the 770's and the most common ones I see are the 80 ohms, and am wondering if they'll be loud enough without an amp to drown out say background noise in a cafe. 

 
There's no way to know unless you specify what will be driving these cans.
 
Be aware that the audio quality of the Beyer DT 770/880/990 cans below 250 Ohms is inferior to those rated 250 Ohms and up.

 

[carb0n67]

Mainly my iPhone 5s and laptop. Yeah I've read a lot of people say that the 770s without an amp don't do it justice. Are there small/portable amps meant for small devices like an iPhone that are fairly cheap? If so I wouldn't mind purchasing a 250 ohm version of the 770 and purchasing an amp.

 

[KG Jag]

You can look to offering from Fiio and others.  Apple products and others (e.g. PC laptops) sometimes interface differently with some of these products.

 

[superjawes]

Very simply--Ohms = resistance.  The higher the number, the harder they are to drive.

This bit isn't entirely true. Really, what headphone impedance is telling you is what kind of power the drivers need to produce the best sound. Lower impedance means more current, higher means more voltage. In this respect, yes, some amps (or integrated amps on your sources) will have trouble driving high impedance headphones, but that difficulty comes from not having high enough voltage on the output to drive your cans, which is not the same "hard to drive" generalization that people tend to make about low efficiency headphones.

When picking an amp, you need to check both of these. Ideally, the amp you choose will also give you an idea of how much power it can deliver across a wide range of impedances so you can get an idea of how versatile it is. The maximum value will typically be given at a lower impedance, and power will fall from there. Amps will better voltage performance will stay closer to the max value than others (compare Schiit's Asgard, Lyr, and Valhalla).

And again, headphones with high impedance will usually be harder to drive. I just wanted to paint a broader picture.

 

[AnttiVahtera]

For the amp, if you decide to go with one, check out FiiO E6. As it has no phone controls or anything of that sort, it doesn't matter what you use it with, iPhone, Android, laptop, makes no difference. It's dirt cheap (under 30€ online), very, very portable (tiny and doesn't weight much anything). And according to reviews, not bad sound quality either. I love mine

 

[carb0n67]

hmm ok thanks for the suggestion! If I have to settle for a 250 ohm 770, i'll look into that amp.

 

[AnttiVahtera]

hmm ok thanks for the suggestion! If I have to settle for a 250 ohm 770, i'll look into that amp.

You may want to look at another AMP also, since the E6 is really not that powerful. I don't know how sensitive the 770s are, but unless they are very, the E6 might not have the output power needed. In that case you might want to ask around for another brand product, or see if the FiiO E11k would be sufficient.

 

[carb0n67]

Hmmm. Okay. Guess I'm going to have to research a bit more about amps.