[DarginMahkum]

Let me add one more thing here. The IEM / headphone impedance is not constant and varies with the signal frequency. For example, average 9 ohm impedance of Andromeda looks like this:

I think the problem here is, as the impedance of the IEM is higher for high frequencies, and low for lower frequencies. With a high output impedance of the source, the amount of transferred signal for the lower frequencies will be lower than the higher frequency signals, which would make Andromeda sound brigher and the frequency balance to be incoherent. If the output impedance is very small (at least compared to the headphone), then nearly the complete signal will be transferred to the IEM / headphone and the difference of lost signal due to the output impedance of the amp will be negligably small, what you will experience will be directly the characteristics of the IEM, not have the amp affect your audio signal.

Again, I think, this is what the LID technology with 64 Audio is: Retain a constant impedance across whole frequency band and thus prevent any uneven transfered signal, making the IEM sound nearly the same for different output impedances - especially important for multi-driver IEMs.

 

[Tristy]

Let me add one more thing here. The IEM / headphone impedance is not constant and varies with the signal frequency. For example, average 9 ohm impedance of Andromeda looks like this:



I think the problem here is, as the impedance of the IEM is higher for high frequencies, and low for lower frequencies. With a high output impedance of the source, the amount of transferred signal for the lower frequencies will be lower than the higher frequency signals, which would make Andromeda sound brigher and the frequency balance to be incoherent. If the output impedance is very small (at least compared to the headphone), then nearly the complete signal will be transferred to the IEM / headphone and the difference of lost signal due to the output impedance of the amp will be negligably small.

Again, I think, this is what the LID technology with 64 Audio is: Retain a constant impedance across whole frequency band and thus prevent any uneven transfered signal, making the IEM sound nearly the same for different output impedances - especially important for multi-driver IEMs.

So the LID tech wouldn’t effect the technicalities such a detail retrieval, wider soundstage etc that a different DAP / DAC may bring it just makes the frequency response the same across all sources?

 

[DarginMahkum]

So the LID tech wouldn’t effect the technicalities such a detail retrieval, wider soundstage etc that a different DAP / DAC may bring it just makes the frequency response the same across all sources?

"LID is a proprietary circuit that corrects the non-linear impedances of the drivers, restoring proper interaction with the source and preserving the desired sound signature."

https://www.64audio.com/lid

It definitely will. But if you have a very high quality amp with very small output impedance, I would expect that the effects are negligibly small. Otherwise if you have a high output impedance player, without LID and very low IEM impedance, the electrical signals will not be uniformly transferred to your IEM accross the frequency band. Especially if you have a multi driver system with varying impedances, you will probably hear an uneven sound.

 

[Pictograms]

There is a good article about output impedance on innerfidelity and how it affects headphone https://www.innerfidelity.com/content/musings-headphone-amplifier-output-impedance

 

[DarginMahkum]

I just took this for the link I sent. For example, for this particular case the impedance for lower frequencies is higher than the higher frequencies so the resulting sound with exaggerated bass.

Then again, my explanation is most probably a very simplified look at the whole mechanics, and I might be well missing some important information. So, make a pinch of salt ready while reading it.

 

[DarginMahkum]

There is a good article about output impedance on innerfidelity and how it affects headphone https://www.innerfidelity.com/content/musings-headphone-amplifier-output-impedance

"Again, look at the impedance plot of the HD800. With a high output impedance amp, the headphones will get a little more gain as the impedance goes up. Therefore, you can think of the impedance curve as an EQ curve with high impedance amplifiers. The higher the amp output impedance, the more the headphones will be EQ'd toward the shape of the impedance curve. In the case of the HD800, the higher the output impedance of the amp, the more you'll get a mid-bass boost centered at 100Hz. "

Which is why by providing a near to flat impedance using LID we should be able to experience the real characteristics of the IEM.

 

[Julio C]

Shanling M6 Vs Fiio M15? I have an M9, planning to upgrade and get more juice to my FH7....thanks...

 

[DarginMahkum]

Just wanted to add (maybe you all already know). LID is not the only one out there to tackle (or rather make a workaround for) the problem:

"Flat Impedance Balanced Armature Earphone (FIBAE™) technology is world’s first, revolutionary, In-Ear Monitor design providing flat impedance and phase. By changing Balanced Armature driver character from inductive to resistive we solved one of the oldest problem in the industry – dependence on output impedance of sound source for correct earphone output. With FIBAE™ technology your earphones will always perform best from any DAP. Single and multi-driver configurations available."

https://thecustomart.com/fibae/

 

[Pictograms]

Shanling M6 Vs Fiio M15? I have an M9, planning to upgrade and get more juice to my FH7....thanks...

M11 is in the same price range as m6, maybe that would be a better comparison for you

 

[Nayparm]

Shanling M6 Vs Fiio M15? I have an M9, planning to upgrade and get more juice to my FH7....thanks...

Just got some in, not had chance to set one up and listen yet but ironically they share the exact same build, shape and dimensions.
The M11Pro Stainless Steel however feels a much more premium device. I won't get chance till tomorrow to take a listen.

 

[Julio C]

I will be staying with my next DAP for years I typically invest and gets off to enjoy music, considering upto 1500 USD, M6 is now at the top of my list, but now trying to understand what I get with the M15, in comparisson, SQ, battery, interface... etc... thanks...

 

[Julio C]

thanks for the physical comparisson... yes I anticipated these 2 would look very similar, gladly that fiio adopted a more smoth form. one thing I noticed from the pictures is that the M15 has the golden rings around the headphone ports, but apparently this is just marketing gimmick

Wainting to hear a comparisson in other attributes, thanks again....

 

[dsrk]

Just got some in, not had chance to set one up and listen yet but ironically they share the exact same build, shape and dimensions.
The M11Pro Stainless Steel however feels a much more premium device. I won't get chance till tomorrow to take a listen.

Will be waiting for your impressions.

 

[cr3ativ3]

Will be waiting for your impressions.

+2

 

[Nayparm]

thanks for the physical comparisson... yes I anticipated these 2 would look very similar, gladly that fiio adopted a more smoth form. one thing I noticed from the pictures is that the M15 has the golden rings around the headphone ports, but apparently this is just marketing gimmick

Wainting to hear a comparisson in other attributes, thanks again....

There will be a golden ring here too but it won't make it sound any better