[hifi nub]

I should have looked at the specs of the E11K. I could have sworn that it was capable of 300ohms. But is capable of 150 ohms.
 
My E11K barely pushes these 250 ohm headphones.
 
I can still travel with these with the portable headphone amp and have decent audio, but while I am at the desktop, I have been sinking my eyes into the Magni 2.
 
I have an asus xonar D1 soundcard with a built in DAC.
 
Is it ok to pair the two up before I go spending money again? Asus xonar D1 & Magni 2? I don't see why there would be any problems. Then even down the road, I can pick up a very nice DAC and stack it with the Magni 2. But for now, the question remains for me.

 

[Me x3]

Hello,
 
E11K should drive your DT770 with no problems at all. Loud enough at 60% with the vast majority of recordings.
 
Some possibilities that come to mind:
 
1- Defective E11K
2- Your input signal to the E11K is extremely low
3- You are listening to music at extreme volume. If this is the case, I must warn you, you might end up with permanent hearing troubles soon, be careful.
 
Best Luck!

 

[billybob_jcv]

Do you have your Windows volume control set to max?

 

[hifi nub]

  Hello,
 
E11K should drive your DT770 with no problems at all. Loud enough at 60% with the vast majority of recordings.
 
Some possibilities that come to mind:
 
1- Defective E11K
2- Your input signal to the E11K is extremely low
3- You are listening to music at extreme volume. If this is the case, I must warn you, you might end up with permanent hearing troubles soon, be careful.
 
Best Luck!

Thanks for the warning! I listen to music at a clear level without ringing which I have done before but don't now. What happens is distortion happens anything over 5-7 on the dial. In which when I hooked up my jvc rx900's, it doesn't happen. I am guessing this is the impedance of the ohms on the beyer's. Harder to drive? The E11K is rated for Drive ability: 16-150 Ohms(recommend). It still drives them but I truly believe these 770's aren't shining as they should be.
 

Do you have your Windows volume control set to max?

Yup, I do so. which my asus software controls vice versa. Since you mentioned this should I dumb the win7 vol control down and up the amp vol and see?

 

[marcswede]

The E11 (the non K predecessor) has two gain switches. One on the side of the housing and one behind the battery. Does the E11K have the same?

 

[hifi nub]

The E11 (the non K predecessor) has two gain switches. One on the side of the housing and one behind the battery. Does the E11K have the same?

The E11K has one gain and one bass. Gain is Low or High. The bass is On or off. There isn't a third switch.
 

 

[marcswede]

The E11K has one gain and one bass. Gain is Low or High. The bass is On or off. There isn't a third switch.

Aha, I see.

It's still weird that you don't get enough power to drive the Beyers without distortion. Spontaneously I would think you either have a defective item or that there's a problem with a weak signal.

Do you feed the Asus via Windows built-in sound driver or digital output (wasapi, Kernel Streaming, ASIO etc.)?

 

[billybob_jcv]

I'll give the opposite view and say that this doesn't really surprise me all that much. As the OP pointed out, the specs of the E11K only rate the amp for headphones up to 150 Ohms. If you look at the power output, the E11K has 450 mW @ 16 ohms and 230 mW @ 32 ohms. By comparison, the Schiit Magni has 1200 mW @ 32 ohms and 260 mW @ 300 ohms. Also, don't forget that the 250 ohm rating of the DT770 is just the nominal impedance, it actually goes over 300 ohms at some parts of the frequency curve.

 

[Me x3]

Higher impedance = easier to drive = less power needed.
The impedance goes over 300 Ohm around the resonance frequency where the driver is much more efficient.
 
I'm not sure why Fiio rate the amp for headphones up to 150 Ohm, I think in the past years they said up to 300 Ohm, not sure.
Some kind of marketing technique in favour of the bigger models probably (E12, E09K)
 
The rating doesn't make much sense anyway because sensitivity is more relevant than impedance.
 
Schiit Magni has a LOT of power, not needed definitely. Still a lot of power for really hungry headphones like K702 or even HE-500.
 
Here the problem could be:
 
-Defective DT770s
-Defective E11K
-Unhealthy listening levels.
 
No way E11K can't drive DT770s really loud without distortion.
 
1) Have you tried your DT770s plugged directly into your laptop to see if they present distortion in a similar way?
 
2) Have you tried your JVC with the E11K's potentiometer up there where DT770s distort and the JVC didn't distort?
 
3) What music are you listening to?

 

[billybob_jcv]

Wait, what? Higher impedance does NOT mean "easier to drive" - impedance is the AC equivalent of resistance - it represents the load placed on the amplifier. The power output of an amp decreases with the load placed on it. The higher the impedance, the less power the amp can supply. A 32 Ohm DT770 will be louder than a 250 Ohm DT770 at the same volume level of the same amp.

 

[Me x3]

Wait, what? Higher impedance does NOT mean "easier to drive" - impedance is the AC equivalent of resistance - it represents the load placed on the amplifier. The power output of an amp decreases with the load placed on it. The higher the impedance, the less power the amp can supply. A 32 Ohm DT770 will be louder than a 250 Ohm DT770 at the same volume level of the same amp.

 
Quite off topic, but hopefully helpful.
 
It's common knowledge in the speaker's world that 8 Ohm speakers are easier to drive than 4 Ohm speakers. That fact discourage many people from buying Dynaudios every year.
 
For a given voltage, a load with low impedance will drain a lot of current, and a lot of current means  (a lot)^2 of Power.
 
If we consider 2 headphones:
 
Headphone A:
30 Ohm
90db/V
 
Headphone B:
300 Ohm
90db/V
 
Headphone A will need much more power than headphone B to sound the same, and thus a much stronger Amp.
 
That's why you can hook 4 high impedance headphones and easily drive them with a single amp.
Doing the same with 20 Ohm headphones you could end up with a broken amp.
 
That said, amps like Fiio E10/E11/E07K/E17 are almost perfect voltage sources for every load between 50 Ohm and 600 Ohm. This means they are capable of provide almost the same clean voltage (Around 2,5 Vrms) no matter the load.
 
2,5 Vrms into 50 Ohm load will push the amp to its limits, where distortion increases: a lot of current = (a lot)^2 of Power
2,5Vrms into 300 Ohm drains very little current, so the amp is far from its limits, so far that you can hook another 300 Ohm load in parallel and the amp is still relaxed and very clean (undistorted)
 
So, as far as you don't need more than 2,5Vrms, higher impedance means easier to drive. (Also easier because of better damping factor)
 
For DT770 250 Ohm version, 2,5Vrms mean something around 110dB SPL, and that's LOUD and also unhealthy for listening sessions over 2 minutes.

 

[PBmaster14]

That's strange you can't play the 770's 250 ohm of your Fiio. I can play them just fine from my laptop.

 

[hifi nub]

Aha, I see.

It's still weird that you don't get enough power to drive the Beyers without distortion. Spontaneously I would think you either have a defective item or that there's a problem with a weak signal.

Do you feed the Asus via Windows built-in sound driver or digital output (wasapi, Kernel Streaming, ASIO etc.)?

@Feeding the asus, I have no idea. Could you explain the two differences and how I may set up the digital output "wasapi"? I keep running into threads talking about wasapi but have no clue what it is, be awesome if you may fill me in. Imho, wasapi sounds like a better output.
 

  Higher impedance = easier to drive = less power needed.
The impedance goes over 300 Ohm around the resonance frequency where the driver is much more efficient.
 
I'm not sure why Fiio rate the amp for headphones up to 150 Ohm, I think in the past years they said up to 300 Ohm, not sure.
Some kind of marketing technique in favour of the bigger models probably (E12, E09K)
 
The rating doesn't make much sense anyway because sensitivity is more relevant than impedance.
 
Schiit Magni has a LOT of power, not needed definitely. Still a lot of power for really hungry headphones like K702 or even HE-500.
 
Here the problem could be:
 
-Defective DT770s
-Defective E11K
-Unhealthy listening levels.
 
No way E11K can't drive DT770s really loud without distortion.
 
1) Have you tried your DT770s plugged directly into your laptop to see if they present distortion in a similar way?
 
2) Have you tried your JVC with the E11K's potentiometer up there where DT770s distort and the JVC didn't distort?
 
3) What music are you listening to?

Yup, that's the same thing I heard ppl talking about is that the e11k upto 300 ohms and is why I bought these headphones. So in the words of sensitivity, these headphones and portable amp should be flawless? I wish I knew of an audiophile that take a listen to these and say hey this is what your problem is etc. The E11K & 770's sound crisp clean and clear but if I up it distortion happens so odd, like an example, the JVC's with bass rattles the upper and bottom teeth if they are a hair width away from each other but the 770's go into distortion. That's the best way I may explain the problem.
1) Wow, ok, I hooked my 770's upto the asus soundcard/DAC they sound GOOD. Hook up to the amp, they sound good but at lvl 5+ they get distorted and it ain't even loud odd. It's not right.
2) This is correct.
3)Trance, techno,dance,rock and rap.
 
This the route of running the sounds. Asus xonar D1>FiiO E11K>DT770's.
 
Edit:
Testing Windows7>FiiO X3 DAC>E11K>770's.
 
Edit:
FiiO X3 DAC>E11K>770's sounds the same way.

 

[billybob_jcv]

Quite off topic, but hopefully helpful.

It's common knowledge in the speaker's world that 8 Ohm speakers are easier to drive than 4 Ohm speakers. That fact discourage many people from buying Dynaudios every year.

For a given voltage, a load with low impedance will drain a lot of current, and a lot of current means  (a lot)^2 of Power.

If we consider 2 headphones:

Headphone A:

30 Ohm

90db/V

Headphone B:

300 Ohm

90db/V

Headphone A will need much more power than headphone B to sound the same, and thus a much stronger Amp.

That's why you can hook 4 high impedance headphones and easily drive them with a single amp.

Doing the same with 20 Ohm headphones you could end up with a broken amp.

That said, amps like Fiio E10/E11/E07K/E17 are almost perfect voltage sources for every load between 50 Ohm and 600 Ohm. This means they are capable of provide almost the same clean voltage (Around 2,5 Vrms) no matter the load.

2,5 Vrms into 50 Ohm load will push the amp to its limits, where distortion increases: a lot of current = (a lot)^2 of Power
2,5Vrms into 300 Ohm drains very little current, so the amp is far from its limits, so far that you can hook another 300 Ohm load in parallel and the amp is still relaxed and very clean (undistorted)

So, as far as you don't need more than 2,5Vrms, higher impedance means easier to drive. (Also easier because of better damping factor)

For DT770 250 Ohm version, 2,5Vrms mean something around 110dB SPL, and that's LOUD and also unhealthy for listening sessions over 2 minutes.

I suspect you are applying the knowledge of speakers and power amps to headphones, and it's really not quite the same thing. In speaker power amps, what you say is absolutely correct. The low impedance of the load and the relatively high voltages cause the amp to be current limited. If the power supply is not beefy enough to supply the required current as the impedance drops, the speaker demands will not be met.

However, most headphones are not high current devices, and most headphone amps are not current limited. Most headphones have significantly more impedance than speakers. It is true that some very low impedance IEMs may require low gain and higher current amps, but that's not the norm for full-size headphones.

http://tinyurl.com/Headphone-Impedance
http://tinyurl.com/Headphone-Power

 

[Me x3]

I suspect you are applying the knowledge of speakers and power amps to headphones, and it's really not quite the same thing. In speaker power amps, what you say is absolutely correct. The low impedance of the load and the relatively high voltages cause the amp to be current limited. If the power supply is not beefy enough to supply the required current as the impedance drops, the speaker demands will not be met.
 

As far as we are talking about dynamic headphones, speakers and headphones are the same thing, so same physics apply.

However, most headphones are not high current devices (neither high voltage devices), and most headphone amps are not current limited. Most headphones have significantly more impedance than speakers.

Is true that many headphone amps are not current limited, at least for loads over 60 Ohm, but this doesn`t change the fact that 2.5Vrms into 60 Ohm means much more power than 2.5V into 300 Ohm (the easy load).

 
In other words, what you are saying is that high impedance headphones are harder to drive because you can run out of voltage. You can run out of voltage but it's not the case here, since 2.5Vrms into DT770 250 Ohm = 110dB (approx). So you have enough voltage for borderline unhealthy levels.
 
Plugging DT880 600 Ohm version directly into an ipod shuffle you won't be able to make them loud, but it's still an easy load that doesn't put the amp to their limits, you can hook 4 DT880 600 Ohm and get the same (shy but clean) performance.
 
I think both of us understand the topic, just that you use 'hard to drive' as a synonym of 'hard to make loud' which of course also depends on sensitivity.
 
At normal listening levels, (lets say) 1.3Vrms for DT770s. At the resonance frequency, the impedance is higher, so it will be easier for the amp to provide 1,3Vrms.