[Mmet]

Tried amping with fiio before ... it kills my favorable sony sound ... yes it measures bad .. BTW i didn't see before a good measuring walkman dap 

 

 ... but i love how they sound ....
 
then amping with the Predator and that was a real bonus and real gain in sound .. but then i missed the openness of that walkman sound ( the predator is dark by nature ) .. and more importantly the portability factor .. i put it in my pocket ... then forget that i am even carrying it in my pocket  .. so i decided to use it as it is ... specially that i use it with a sensitive iem in range of vol. 12-15 ( its ideal sounding state ) 
 
to sum it up : it is a great device as it is ... use it as intended and it will not disappoint 

 

[nekromantik]

Just a heads up, im putting my A25 HK version on the for sale section this weekend.
No EU limit and very good condition.
Thinking about £100. Too high?

 

[zilch0md]

 

Spoiler: Warning: Spoiler!

I guess it is never too old to use the  'you probably don't know what you are doing' argument

. No offence taken, but let's look at some graphs.
 
 

First, let's look at what a typical 1kHz pure tone coming out of a decent DAP looks like. Here is FiiO X5II's headphone-out at volume 88, giving roughly the same voltage as A10's LO. Since it is a 1kHz pure tone, we shouldn't see any extra peaks beside the 1kHz (*and we didn't). Background noise is mostly under -120dBV, which is about -108dB from the 1kHz peak.
 
 

Here is A10 are volume 14/30. As I have commented before, this is where A10 behaves at its best. Pushing the volume up eventually will increase distortion.
 
 

This is how A10 LO looks like with all EQ and HSEE disable (same condition for all the following graphs) - notice there are a lot of unwanted small peaks after the 1kHz tone. We know these are harmonic distortion because they are mainly the multiplied frequencies (2kHz, 3kHz, 4kHz, etc) of our 1kHz fundamental frequency.
 
 

Here is what A10 looks like at 24/30 volume - notice the voltage output is almost the same as LO. Still have lots of harmonic distortion, but just a tiny bit cleaner than LO. Ironic actually.
 
 

This is how A10 looks like at 30/30 (maxed out) - rather horrible. You don't need to be an engineer to know why maxing out the volume is such a bad idea. Also take note that 30/30's voltage is in fact almost double that of LO.
 
 

Here is A10's LO feeding E12A (with a 47ohm load, set to roughly gain of 1 *no amplification*). E12A is doing such a great job and being so transparent that it reproduces the exact harmonic distortions from A10's LO, hence why this graph looks so alike to the LO graph above.
 
 

 
A10 at 24/30 feeding E12A, looking just like A10 at 24/30 without E12A. Again, E12A is doing its job as described.
 

A10 at 30/30 feeding E12A, same thing.
 
 

Just for good measure, this is A10's LO with HSEE enable, just to show you how much crap HSEE throws into the mix when you compared it to pure LO. Perhaps the only comforting news is that they are mainly even harmonic, which means they are not quite as offensive to the ear.

 

 
You've dropped a big sledge hammer on this topic. Thanks for all the effort!  I'm edified beyond answering the question at hand.

 

[zilch0md]

 
 I can use my A17 without an external amp and my B&W P5 S2 and get decent volume.  But adding the E12A gives me a fuller sound with more impact and a bigger sound stage.  Having that extra power in an external amp isn't just for added volume it can improve the listening experience as well.  I do find the A17 sound to be a little to cold and analytical and adding a warmer sounding amp can subdue those qualities and to me sounds better.  If find the A17 sound fatiguing  without using and external amp.

 
Well said.
 

  I had a chance to compare my A17 + E12A combo to a ZX100 (salesman sample) and I found the sound quality very close between the two.  Given that importing a ZX100 would cost me about $400.00 more than what I paid for my A17 + E12A combo I will take my combo and save the money every time.  To me the only advantage of the ZX100 is the extra 64 GB of storage which is not worth $400.00 and I get a lot more power with my E12A.  As I don't need the NC feature of the ZX100 since I don't use Sony headphones it is of no use to me. 

 
Were you using your (efficient) B&W P5 S2 when comparing the A17+E12A to the ZX100?  
 
A less efficient headphone would not have performed as well with the ZX100's 15mW into 16 Ohms vs. the E12A's 420mW into 16-Ohms.  

 

[castleofargh]

   

Spoiler: Warning: Spoiler!

 
 I have had my A17 doubled amped with a Fiio E12A and the A17 volume maxed out for months now and no distortion at all.  In fact I find I get the best sound with the A17 maxed vs a lower volume setting when double amping.  I believe Sony is using fixed volume output at max volume for use with an external amp as it does not have a true LO implementation.  Are you sure you are using your analyzer properly?  I think I will trust my ears thank you very much.

 
I guess it is never too old to use the  'you probably don't know what you are doing' argument

. No offence taken, but let's look at some graphs.
 
 

First, let's look at what a typical 1kHz pure tone coming out of a decent DAP looks like. Here is FiiO X5II's headphone-out at volume 88, giving roughly the same voltage as A10's LO. Since it is a 1kHz pure tone, we shouldn't see any extra peaks beside the 1kHz (*and we didn't). Background noise is mostly under -120dBV, which is about -108dB from the 1kHz peak.
 
 

Here is A10 are volume 14/30. As I have commented before, this is where A10 behaves at its best. Pushing the volume up eventually will increase distortion.
 
 

This is how A10 LO looks like with all EQ and HSEE disable (same condition for all the following graphs) - notice there are a lot of unwanted small peaks after the 1kHz tone. We know these are harmonic distortion because they are mainly the multiplied frequencies (2kHz, 3kHz, 4kHz, etc) of our 1kHz fundamental frequency.
 
 

Here is what A10 looks like at 24/30 volume - notice the voltage output is almost the same as LO. Still have lots of harmonic distortion, but just a tiny bit cleaner than LO. Ironic actually.
 
 

This is how A10 looks like at 30/30 (maxed out) - rather horrible. You don't need to be an engineer to know why maxing out the volume is such a bad idea. Also take note that 30/30's voltage is in fact almost double that of LO.
 
 

Here is A10's LO feeding E12A (with a 47ohm load, set to roughly gain of 1 *no amplification*). E12A is doing such a great job and being so transparent that it reproduces the exact harmonic distortions from A10's LO, hence why this graph looks so alike to the LO graph above.
 
 

 
A10 at 24/30 feeding E12A, looking just like A10 at 24/30 without E12A. Again, E12A is doing its job as described.
 

A10 at 30/30 feeding E12A, same thing.
 
 

Just for good measure, this is A10's LO with HSEE enable, just to show you how much crap HSEE throws into the mix when you compared it to pure LO. Perhaps the only comforting news is that they are mainly even harmonic, which means they are not quite as offensive to the ear.

 

14/30 volume is pretty nice indeed. kind of makes me want to stop saying how the sony can't output a clean signal.
and for most IEMs I end up around those values or lower, so I guess it works out well in practice.
now with an amp and a less sensitive headphone, that's really low output voltage. it's a lot of gain to add just to get around 1volt. do you use a 0db 1khz or a lower value signal that should be added to the voltage reading?
 
 
on topic of the sony maxed out, I would say it was kind of obvious that it wouldn't be ideal. else why would sony chose to go quieter on the LO? the output is weak and they decide to give up on some potential SNR db, only some other bigger problems could justify that kind of decision.
 
thanks a lot ClieOS, it takes time to do measurements and I appreciate you doing those for us.

 

[zilch0md]

Sadly, for those of us who want to use less efficient headphones, every Sony Walkman (including the NWZ-A17 and ZX100, and no doubt Sony's future offerings) provides us with an excellent UI, file format support, and card reading features, that are accompanied by their "just good enough," proprietary sigma-delta DAC, and a very weak Line Out and Headphone Out (suitable only for efficient IEMs and headphones).
 
- b e c a u s e - 
 
They design their products to satisfy Joe Consumer, not Joe Audiophile. They must do this to get the sales volume required to cover the cost of research, development, manufacturing, and perhaps the very best quality control of any line of DAPs currently made.  Joe Consumer wants small, easily carried, pocketable mobile devices that can be recharged via USB jacks, with batteries that last a long time between charges. Those requirements are in direct contention with the high power output needed by many of Joe Audiophile's favorite headphones.
 
That's why I'm so very content with using the Sony NWZ-A17 with the aftermarket USB emulation cable, bypassing the Walkman's DAC and amp, to drive the Oppo HA-2's excellent ESS9018K2M DAC.  And when the HA-2 doesn't provide enough power for a given headphone, I use its Line Out to drive the iBasso PB2.  
 
We just can't have it all in one tiny package - not until battery technology takes a giant leap forward. 

 

[Raketen]

Is ZX100 really that weak? I'd read somewhere it has similar specs to the ZX2 so I guess ZX2 isn't so great either.
Disappointing. I bought an AK Jr. for cheap recently, great sound but glitchy UI and limited functionality. Was hoping ZX100 might be the solution since I like the A10 already.
 

 
We just can't have it all in one tiny package - not until battery technology takes a giant leap forward. 

We're almost there- Imagine if sony made the PHA amps with the H x W dimensions of the A10 and a modular backplate or something. Or even just a less 90/l-shaped WmPort OTG cable (that aftermarket cable for the Oppo doesn't work with everything unfortunately).
 
I think it's more a question of manufacturer will than battery tech. They seem to have an annoying habit of avoiding somewhat basic functionality options with their lower budget-tier devices, like w/ my Jr. Or the new Cowon Plenue D that has 100 hrs batt life, better headphone output than the A10, but no line or digital out. Or if Shanling m2 or xDuoo x3 had Walkman UI.
 
Even something like the Fiio M3 if it just had line & digital out, would be insanely versatile- enough power on its own for a lot of stuff & a tiny transport for whatever dac/amp people wanted.
 

 

[cosie]

interesting to see a graph with Clear Audio enabled

 

[zilch0md]

  [snip]
 
We're almost there- Imagine if sony made the PHA amps with the H x W dimensions of the A10 and a modular backplate or something.
 
[snip]
 
I think it's more a question of manufacturer will than battery tech. 
 
[snip]
 

 
I'm afraid that's wishful thinking.  The manufacturers already have the will to make these products smaller, as evidenced by the A10 series Walkman, but battery tech is indeed the roadblock to offering higher current and/or voltage to the headphone out.  
 
Even the Sony portable amps are weak relative to other offerings, because they've made the (smart) choice to sell into the much larger (Joe Consumer) market that demands long play times between charges and also likes being able to charge their mobile devices from any 5V USB port (instead of hauling around a charger of some kind.)
 
Quoting a post I made to the PHA-2 thread: http://www.head-fi.org/t/680208/sonys-dsd-capable-pha-2-portable-headphone-amp-dac/240#post_9949418
 

The PHA-2 uses a chip, called the Texas Instruments TPA6120, that's capable of outputting 1500 mW into 32Ω when given a 12V supply voltage (with a larger battery) and a whopping 2000 mW into 32Ω, with a 15V supply voltage (with an even larger battery).  
 
See Figure 8, on page 8 of the TPA6120A2 data sheet: http://www.ti.com/lit/ds/symlink/tpa6120a2.pdf
 
Which begs the question:  What Vs (supply voltage) is Sony using with the TPA6120 in the PHA-2?  
 
Answer:  Per their specs page -   
 

1. Power Source : DC 3.7 V Built-in lithium-ion rechargeable battery    

That's why the PHA-2's TPA6120 isn't putting out 2000 mW into 32Ω. That chip needs 12V for 1500 mW, or 15V for 2000 mW (into 32Ω).  
 
The PHA-2 is using a small one-cell, 3.7V battery [to keep the weight and size down to what Joe Consumer expects.]

 
And thus, with Sony's choice to use a small, single-cell 3.7V Li-Ion battery, that can be charged from any 5V USB port, their PHA-2 specs show it can only put out 90 mW into 32Ω - all the while using a chip that's capable of 2000 mW into 32Ω, if you supply it with 15V, but that would require a much larger battery (not to mention heat sinks), especially if you wanted to maintain the same play time that can be had putting out only 90 mW. People have reported in the Sony PHA-2 thread that they can manage no more than 6.5 hours on a full charge, when using both the DAC and the amp sections.
 
As a point of reference, the Oppo HA-2 has a play time of 7 hours, when using both the DAC and amp, despite managing an output of 220 mW into 32Ω. I'll take the additional power that comes with a larger, heavier battery, any day.  7 hours does not inconvenience me and the Oppo HA-2's rapid charger can do wonders (about 50% of full charge) in just 30 minutes - because I'm willing to carry it and find an AC outlet when needed, which Sony seems to think Joe Consumer abhors.  
 
They may be right. And there's no way Sony can offer such great design and quality control without tailoring their products to the wants of the masses (small, lightweight devices with long play times) for a higher volume of sales, rather than catering to the needs of the much smaller "audiophile" market (putting performance ahead of convenience). I think Oppo's HA-2 has found a sweet spot that can satisfy both markets.

 

[ClieOS]

  interesting to see a graph with Clear Audio enabled

 
Here is what A10's LO with ClearAudio+ enable:
 

At fist look, and if you compare it to the original A10's LO graph below, you will notice we see less harmonic distortions and a higher voltage output - all seems to indicate that ClearAudio+ is actually making the audio clearer. So does ClearAudio+ really works? Well, not entirely. For the explanation, we need a third graph on how ClearAudio+ does to frequency response. please read down.
 
 

 
 

 
Here is the difference between the normal A10's LO vs. LO with ClearAudio+ enabled - First, you can see ClearAudio+ has boosted the 1kHz region slightly, thus explaining why an increase in output voltage in the first graph (*remember that graph is a 1kHz pure tone). Secondly, the decrease of harmonic distortion is not actually because ClearAudio+ has a better digital processing, but simply because it attenuated the 1.5kHz~9kHz region and therefore made the harmonic distortion 'disappear'. As the saying goes, there is no free lunch.

 

[gerelmx1986]

 

  interesting to see a graph with Clear Audio enabled

 
Here is what A10's LO with ClearAudio+ enable:
 

At fist look, and if you compare it to the original A10's LO graph below, you will notice we see less harmonic distortions and a higher voltage output - all seems to indicate that ClearAudio+ is actually making the audio clearer. So does ClearAudio+ really works? Well, not entirely. For the explanation, we need a third graph on how ClearAudio+ does to frequency response. please read down.
 
 

 
 

 
Here is the difference between the normal A10's LO vs. LO with ClearAudio+ enabled - First, you can see ClearAudio+ has boosted the 1kHz region slightly, thus explaining why an increase in output voltage in the first graph (*remember that graph is a 1kHz pure tone). Secondly, the decrease of harmonic distortion is not actually because ClearAudio+ has a better digital processing, but simply because it attenuated the 1.5kHz~9kHz region and therefore made the harmonic distortion 'disappear'. As the saying goes, there is no free lunch.

 
Non sense, numerican and visual NON SENSE, you cannot hear the graphs LOL, I bet clieOS doen't enjoy the music at all, he uses it for analysing his device   ​

 

[ClieOS]

   
Non sense, numerican and visual NON SENSE, you cannot hear the graphs LOL, I bet clieOS doen't enjoy the music at all, he uses it for analysing his device   ​

 
Denial is not exactly a way to progress.
 
Besides - I just enjoy it more when it is under 14/30 in volume with HSEE and EQ off, that's all (and in the regard, I still quite enjoy my A10 and use it the most out of all my DAP because of its convenient size and as a digital source). You can of course enjoy it whichever way you like. Don't let how I enjoy my music offends you

 

 

[gerelmx1986]

 
Denial is not exactly a way to progress.
 
Besides - I just enjoy it more when it is under 14/30 in volume with HSEE and EQ off, that's all (and in the regard, I still quite enjoy my A10 and use it the most out of all my DAP because of its convenient size and as a digital source). You can of course enjoy it whichever way you like. Don't let how I enjoy my music offends you

 

I also don't listen past 15 on the walkman volume... (too loud LOL), my average volumes are for
 
IEMs (XBA-A3) between 06 -07(rare) 08-10 (common), 11 or 12 (rare: depends on liudness of master)
Full-size cans (MDR-1R) (need to go to germany to my BF's house and get a listen to my ex-Ultrasones HFI-780): 08-12 (common) and 14 or 16 (rare, like IEMs, depends on loudness of master)
for Car AUX-IN i do drive up to 24 or MAX (30), anyways ina  car you can't really distinguish and i need these volumes to be able to feed the stereo to a listeaneable level (damn sony weak output)
 
auch so: (oops, german, LOL) Also: I don't turn any audio enhancers... I have all flat

 

[castleofargh]

if clear audio was boosting around 2.5 or 3khz instead of 1khz, I bet voices wouldn't sound so weird.
 
 
 
Quote:

  Non sense, numerican and visual NON SENSE, you cannot hear the graphs LOL, I bet clieOS doen't enjoy the music at all, he uses it for analysing his device   ​

do we lose our soul the day we learn that 2+2=4 or understand ohm's law? I thought only redheads had no soul from the scientific documentaries called "south park".

 

[cosie]

ClieOS thanks a lot for the measurements,
Please last question, very interesting for me question regarding EQ impact on the SQ.
Could you please make a LO and volume 24/30 graphs of the frequency response and harmonic distortions with flat EQ but just Clear BASS enabled, lets say +2 points?