[aman Stark]

hello, 
 
this is my first post and i have read a lot here before and now i am thinking about purchasing the e11, i live in hong kong so it's quite hard to find other amps here. until now i have only find fiio's at this price.
i would be very thankful if someone can tell me how well the UE TF10 does with e11, i only need the amp for my iphone 4s and only wants to boost a little bass and should i also purchase the LOD . 

 

[imackler]

Definitely purchase a LOD. I think since the E11 has the bass boost you can't go wrong with the E11! Such a good amp for so little money!
 
Quote:

hello, 
 
this is my first post and i have read a lot here before and now i am thinking about purchasing the e11, i live in hong kong so it's quite hard to find other amps here. until now i have only find fiio's at this price.
i would be very thankful if someone can tell me how well the UE TF10 does with e11, i only need the amp for my iphone 4s and only wants to boost a little bass and should i also purchase the LOD . 

 

 

[aman Stark]

Thanks imackler, which LOD do you think is good? how bout Fiio L9?.
Quote:

Definitely purchase a LOD. I think since the E11 has the bass boost you can't go wrong with the E11! Such a good amp for so little money!
 


 

 

 

[imackler]

That's what I'm using. I think it works great!
 
Quote:

Thanks imackler, which LOD do you think is good? how bout Fiio L9?.


 

 

 

[Bill-P]

 
Quote:

There is no such thing as max impedance for most modern solid state amp. The question is whether it will be enough gain (volume). E11 should be able to drive 300ohm headphone that has high enough sensitivity, but to be on the safe side, I'll say 250ohm and below.

 
I just got an Objective 2 amp in from JDS Labs, and I can pretty much say that with the O2 in the picture, I could definitely hear the limitations of the E11 in terms of power. My DT990 Pro 250Ohm seemed to hit the roof with the E11 very often, especially with heavy bass passages. Distortion was inevitable. With the O2, there was no distortion even at volumes that I can't listen to.
 
So I would say that the E11 is better suited for lower impedance cans. Around 250 Ohm is seriously pushing it.
 
But as a side note, the O2 didn't have any bass boost option, so I thought about chaining source -> E11 -> O2, and the result was like an E11 with a lot more power and authority. It was very satisfying, and Bass Boost level 2 on E11 didn't really sound as bloated. That's simply amazing.

 

[aman Stark]

thanks for the help, i guess i will be getting the E11 and L9 then. 

 cheers
Quote:

That's what I'm using. I think it works great!
 


 

 

 

[ClieOS]

I just got an Objective 2 amp in from JDS Labs, and I can pretty much say that with the O2 in the picture, I could definitely hear the limitations of the E11 in terms of power. My DT990 Pro 250Ohm seemed to hit the roof with the E11 very often, especially with heavy bass passages. Distortion was inevitable. With the O2, there was no distortion even at volumes that I can't listen to.
...

As I have mentioned before, the key is having 'high enough sensitivity'. E11 can still fail to drive a pair of 32 ohm headphone well if it has with very low sensitivity, while it can still drive a pair of 250 ohm headphone well enough if sensitivity is high enough. How well an amp driver a headphone is more than just impedance. It also involve sensitivity and on a less important, power requirement. Might also worth noting that impedance rating is generally done on 1kHz, and it is usually not the same across the whole frequency range - that also affect how well a particular amp will drive the headphone and how the headphone will react.

Of course, there is also no denying that O2 is one of the best portable amp around, capable of competing with amp the cost double or triple its price. E11 is good, just not that good. Though personally, I see very little point on double amping with E11 + O2.

 

[Bill-P]

Quote:

As I have mentioned before, the key is having 'high enough sensitivity'. E11 can still fail to drive a pair of 32 ohm headphone well if it has with very low sensitivity, while it can still drive a pair of 250 ohm headphone well enough if sensitivity is high enough. How well an amp driver a headphone is more than just impedance. It also involve sensitivity and on a less important, power requirement. Might also worth noting that impedance rating is generally done on 1kHz, and it is usually not the same across the whole frequency range - that also affect how well a particular amp will drive the headphone and how the headphone will react.
Of course, there is also no denying that O2 is one of the best portable amp around, capable of competing with amp the cost double or triple its price. E11 is good, just not that good. Though personally, I see very little point on double amping with E11 + O2.

 
I am not saying that the E11 is bad, though. Just that I could hear distortion at the same level (in terms of volume) compared to the O2. My understanding is that it has more to do with how much the amp can push out rather than how loud it can make the music go. This is also about the same with E11 vs CmoyBB where I can obviously hear distortion with CmoyBB at much lower volume than I thought possible with the DT990 Pro (no hope at all with DT880). If it's just to make things loud, I think the E11 does a very adequate job with my DT990 Pro (obviously not with the DT880 600Ohm). It's just the occasional distortion that bothered me. The O2 completely eliminated any sort of distortion.

The way I understand it, the O2 is only supposed to add more power and volume to the original source without coloring. In which case, by double amping E11 + O2, it'll just be like I am adding more power to the E11.
 
I sincerely like the sound signature of the E11, and I think that if a higher-power version of it (as a desktop amp) were to exist in an enclosure like the O2, I would buy it in a heartbeat.
 
Edit: and I think I didn't answer the question completely. The reason why I'm double amping is more because the O2, by itself, really does seem to not add anything to the source, which makes it very flat to my taste. I tend to like a bit more bass emphasis to my music, so the E11 is there in the chain specifically for that task since I can't quite recreate what the E11 does to the sound signature with EQ. Also a nice benefit is that the E11 also cleans up high frequencies a bit, too, which makes it more transparent compared to the source to my ears. Well, it's just my personal preference in any case.

 

[ClieOS]

I am not saying that the E11 is bad, though. Just that I could hear distortion at the same level (in terms of volume) compared to the O2. My understanding is that it has more to do with how much the amp can push out rather than how loud it can make the music go. This is also about the same with E11 vs CmoyBB where I can obviously hear distortion with CmoyBB at much lower volume than I thought possible with the DT990 Pro (no hope at all with DT880). If it's just to make things loud, I think the E11 does a very adequate job with my DT990 Pro (obviously not with the DT880 600Ohm). It's just the occasional distortion that bothered me. The O2 completely eliminated any sort of distortion.


The way I understand it, the O2 is only supposed to add more power and volume to the original source without coloring. In which case, by double amping E11 + O2, it'll just be like I am adding more power to the E11.

I sincerely like the sound signature of the E11, and I think that if a higher-power version of it (as a desktop amp) were to exist in an enclosure like the O2, I would buy it in a heartbeat.

Edit: and I think I didn't answer the question completely. The reason why I'm double amping is more because the O2, by itself, really does seem to not add anything to the source, which makes it very flat to my taste. I tend to like a bit more bass emphasis to my music, so the E11 is there in the chain specifically for that task since I can't quite recreate what the E11 does to the sound signature with EQ. Also a nice benefit is that the E11 also cleans up high frequencies a bit, too, which makes it more transparent compared to the source to my ears. Well, it's just my personal preference in any case.

Just an advice - when it comes to amp, you need to volume match all the amps in comparison to (at least) within a 1dB. You might be surprise of how just a few dB of volume can totally change your opinion when A/B'ing.

O2 is designed to be as transparent as possible so you are free of any coloration while having the best possible performance, at least that's the designer's intent. Putting an E11 before it is really just adding unnecessary adding coloration as well as worsening the SNR. Not to say you can't do it or the result isn't enjoyable, just that it seems to contradict what O2 is supposed to do. But at the end, I guess it is the user who should decide what sounds best for his/her ears.

 

[Bill-P]

Well, I did try to volume match the amps, but without proper measuring tools, the best I can do is with my ears, and I suspect it's off by more than 1dB in most cases.
 
But the problem is still that past level 6 on Fiio E11, the DT990 Pro would start distorting, whereas with O2, it would go much louder without distortion, though without the same bass power.
 
You are right in that the O2 is very transparent, though, and I do use it standalone with just the Fiio D3 DAC directly when I'm using the DT880. It's with the DT990 that I chain the E11 in to boost bass, because the E11 does a very good job of keeping the bass under control to me. The DT990 is already inaccurate to begin with, so I don't really worry that much about adding coloration to it. Just that the E11 alone doesn't have enough power to push bass without distortion.

 

[kenman345]

The ZO2 is still $100 on Amazon, even from digiZoid when purchased through Amazon, thus it should still qualify

 

[Mirrood]

I don't know why because I'm an audio newbie but FiiO L9 makes this amp sound much cleaner and better. It went from a little improvement to a lot of improvement after I used the L9.

 

[ClieOS]

Well, I did try to volume match the amps, but without proper measuring tools, the best I can do is with my ears, and I suspect it's off by more than 1dB in most cases.

But the problem is still that past level 6 on Fiio E11, the DT990 Pro would start distorting, whereas with O2, it would go much louder without distortion, though without the same bass power.

You are right in that the O2 is very transparent, though, and I do use it standalone with just the Fiio D3 DAC directly when I'm using the DT880. It's with the DT990 that I chain the E11 in to boost bass, because the E11 does a very good job of keeping the bass under control to me. The DT990 is already inaccurate to begin with, so I don't really worry that much about adding coloration to it. Just that the E11 alone doesn't have enough power to push bass without distortion.

I suspect it is a current limiting issue. Perhaps DT990 is just asking too much current that it is beyond E11 capability. Don't forget O2 uses 2 opamp parallel in each channel to get more current output than most portable amps. Dual 9V supply also plays a big factor too.

The ZO2 is still $100 on Amazon, even from digiZoid when purchased through Amazon, thus it should still qualify

Well, Amazon is limited to North America only. So that's pretty much a 'local' price.

I don't know why because I'm an audio newbie but FiiO L9 makes this amp sound much cleaner and better. It went from a little improvement to a lot of improvement after I used the L9.

Which amp are you using?

 

[Totally Dubbed]

I still don't understand how the E11 nor E6/5 has less hissing than the ZO2.
Same goes for EMI on the A10 vs ZO2...

 

[ClieOS]

I still don't understand how the E11 nor E6/5 has less hissing than the ZO2.
Same goes for EMI on the A10 vs ZO2...

Unfortunately there is no one near me who owns a ZO2 that I can borrow, or else it would be relatively easy to determine if it is my ZO2's issues or it is indeed every ZO2's issue. For now, I can only follow the result of the test.