[Dobrescu George]

  And you really need to make sure that whatever you are listening to is in exactly the same position.  If it's IEMs, don't move them.  Headphones, don't move them.  Speakers are a real challenge because moving your head an inch can evoke big changes due to room acoustics.  These are often overlooked.
 
Have you ever wondered why the same set-up from same tune on the same signal source to earphones can sound different one day to the next?  One reason is that you never get whatever is making the sound inexactly the same place. 
 
Another is that your response varies with mood and weather...there are days when tracks I love just sound awful.

Interesting take on this. 
 
I always thought that people ignored their moods, when trying new equipment or testing their own.
 
If you take into account this thing, it might be that even with volume matched it is hard to be entirely objective when ab-ing. 

 

[Brooko]

  Interesting take on this. 
 
I always thought that people ignored their moods, when trying new equipment or testing their own.
 
If you take into account this thing, it might be that even with volume matched it is hard to be entirely objective when ab-ing. 

 
Given that for an individual short test, your frame of mood is unlikely to alter during the test, blind, volume matched ab testing (abx if possible), its still very reliable.
 
Audio Bear's comments would be valid (on mood) if your test was spanning hours/days

 

[AudioBear]

Yes, I meant the comment as "one day to the next"
 
There is a good chance that if we are wearing cans or IEMs and do our comparison testing on exactly the same rig at balanced volume with a silent invisible switch thrown by some else that we can tell one piece of gear in the chain from another.  That's still not an ABX test but people who read these forums are pretty good listeners and can probably detect audible differences.  Where it gets tough when you have a device like the FiiOX5 is versus the "latest greatest DAP (maybe the X5-II) is telling where the difference comes from.  That has to be dissected module by module--if you even care.  LO does sound better to me...
 
But will it sound better the next day?  Maybe not.  How many times have you cued up a favorite track and then just skipped it?  Why?  Mood!  Or physical and psychological state.  Or whatever.

 

[PinkyPowers]

It's impossible to be entirely objective. Organic bags of meat don't interpret stimuli in hard numerical values. Still, we do the best we can.

 

[x RELIC x]

Who you callin' an organic bag of meat?! Oh, right. :tongue_smile:

 

[Dobrescu George]

  It's impossible to be entirely objective. Organic bags of meat don't interpret stimuli in hard numerical values. Still, we do the best we can.

Actually,
 
Interesting reads:
 
https://en.wikipedia.org/wiki/Ion_channel
 
https://en.wikipedia.org/wiki/Voltage-gated_ion_channel
 
https://en.wikipedia.org/wiki/All-or-none_law
 
By studying these things, I am trying to isolate what makes up the data the brain can process. In particular I want to understand how fine can the data be before there are no differences perceived by human ear/brain in an ideal working condition body. All or none law works mostly for heart, from my understanding, but in this aspect, it is a zero or one response, so not all data in the human body is processed subjectively. In that particular instance, there is only a zero or one condition, like digital data. 
 
I stumbled upon the all or none law while studying ion channels, and how they work, and I think that it is an most intriguing read.

 

[x RELIC x]

Off Topic:

Spoiler: Audible time domain jitter issues:

George, I don't know if you've seen this but it's very interesting and I thought you would enjoy it. Others may find it interesting as well so I'll post it here.


[VIDEO]https://m.youtube.com/watch?v=JYjHKv2_OqQ[/VIDEO]

 

[Mr.Tom]

Something I meant to bring up a while back(when I still had my first X5). I did a bit of A/B testing. And the one thing I found was if you work the op-amps hard, they got cold sounding very fast.
 
When I ran the x5 loud thru my HD650's, I needed to raise the volume past 85, and I found this was the point where the op-amps fell apart. If I ran the x5 with low impedance cans, the sound remained smooth as silk. 
 
I belive this is the reason that some reviewer have claimed the X5 can get shouty, or have steely highs. On portable type headphones the X5 SQ is Stellar!(imo). This is why I bought a second unit.

 

[danmlr]

To volume match you want to use a calibrated single tone (usually 1 kHz as it's the frequency we are most sensitive to). That way you can get the two devices you are testing to pretty much the exact volume. Then after they are matched, make sure you use the same music files on the devices you are testing. Finally, if you can get someone to help you, get them to do any switching so you don't know which one you are listening to.

What is it you want to compare?

Ah, perfect. 
 
This is a great reference post for anyone who wants to do a/b testing to write a review. 
 
I'm comparing the X3II and X5 now. As I have said before, I am a bit disappointed with the X3II sound quality--perhaps I am not volume matching properly? I use exactly the same setup otherwise: same headphones, same amp, same files. I am actually using the same sd card as well (not that that would make a difference). 
 
The HO on the X3II has soft treble: reminiscent of the sansa clip, although not quite that "bad."
 
Some are suggesting I'm not volume matching, so perhaps that is a factor. I read a review on headfonia or headfonics which made this same point, however. 
 
I am either selling or returning the X3II. Very nice design, great portability, but it is a noticeable dropoff from the X5 where it matters most: SQ.

 

[Brooko]

And that is where ultimately you must make the decision
 
If you've removed as many outside influences as you can (when you compare), and then come to a conclusion, then you know that for your hearing, and your preferences, you've made the correct decision.  The trick is not to make a blanket assumption thinking everyone will hear the same.
 
The X5 is a fine choice, as is the X3ii.  I'm just lucky enough that I don't have to make a decision between the two of them.

 

[bretemm]

Will the Fiio X5 gen2 ever be avalible at bestbuy? I don't really like ordering off line,
I'm looking at eather getting Fiio or astell and kern, ak100ii vs Fiio x5 g2, which is better?

 

[PinkyPowers]

Will the Fiio X5 gen2 ever be avalible at bestbuy? I don't really like ordering off line,
I'm looking at eather getting Fiio or astell and kern, ak100ii vs Fiio x5 g2, which is better?

 
You mean "on-line". You made that mistake the first time you asked, also. And I completely understand. If the major portion of my income was criminal, I wouldn't like on-line shopping either. You must find yourself a good money-launderer; someone who doesn't take more than 15%.

 

[bretemm]

Huh? Yea I like to just save up and just go get whatever it is, I trust bestbuys site, Im just not familiar with the fiio provider sites that are listen for the usa, as well as astell&kern

You mean "on-line". And I completely understand. If the major portion of my income was criminal, I wouldn't like on-line shopping either. You must find yourself a good money-launderer; someone who doesn't take more than 15%.

 

[Mr.Tom]

B&H photo is one of the best internet sites for Camera and audio gear.
 
And I'll clean your money for 25%.

 

[bretemm]

B&H photo is one of the best internet sites for Camera and audio gear.

And I'll clean your money for 25%.

Haha thanks! So between the x5 gen2 and the ak100ii, which is better?