[DJ The Rocket]

Regarding sound quality of aptx vs AAC, here's what Darko has to say:

"Bluetooth audio is still sent from iPhone 7 to Airpods, or any other Bluetooth headphone, using AAC – Apple’s ‘own’ lossy codec of choice. In theory and reality this diminishes the listening experience when directly compared to an aptX-piped Bluetooth pairing...For those toting a pair of Sennheiser Momentum Wireless headphones, an Astell&Kern XB10 Bluetooth amplifier or a Wyred 4 Sound bLINK, better sound quality will more-than-likely result from pairing with an aptX-equipped smartphone – i.e. not the iPhone 7."

And theheadphonelist:

"For those concerned with audio quality, at least for the time being, aptX seems to be the solution to beat."

That said, while i was researching this, i found out that some people actually store music in .AAC files. I did not know anybody did that. So presumably, **IF YOUR MUSIC IS ALREADY SAVED IN AAC FORMAT** (and it was encoded from a lossless file to begin with), in this scenario, AAC will most likely sound the best, for the same reason that using the inexplicably shunned mp3 codec would sound best, if you had compatible hardware [that doesn't actually exist]. In all other scenarios, aptx will sound the best

 

[The Walrus]

This is a strange comment. You don't actually have an XB10, do you?

You say "the purpose of this little device is convenience." That's pretty closed-minded, don't you think? Why is it impossible for its purpose be both quality AND convenience? And since when is lossless the standard for quality? I'm not convinced that anybody can consistently tell the difference between a 320kbps mp3 and a flac; indeed, 256kbps mp3s are transparent to the majority of listeners. Aptx HD claims to meet that standard, a claim i have no trouble believing, considering how close aptx already is. In fact, with the Audeze Sine (my portable headphone), the XB10s balanced signal already sounds better than a wired connection to the majority of smartphone headphone jacks.

Your attack on the iPhone 7 makes even less sense. You (along with me and nearly everyone with a head-fi account) aren't going to be happy with the standard headphone jack on almost any nonspecialist equipment, which means we're using an external DAC. What difference does it make if it gets the signal through a USB OTG cable or a lightning cable?

No, it's not close-minded at all. Of course you should go for SQ; that's what this whole forum is all about. But I think it is pointless to argue about the quality of Bluetooth protocols when there isn't really much difference to be honest. 
I completely agree about your comment on mp3. However, if XB10 sounds better than a wired connection, that means that your source's H/O is inferior; it doesn't mean that APT-X HD or any bluetooth protocol is better than a wired connection. 

My attack on iPhone 7 was half joke; but let me tell you this: I recently bought a Huawei Mate 9 (a 6" phablet) and the SQ is superb for a mobile device. It drives my DT 1350 efficiently and I'm quite happy with it. (Which was what Apple could have easily done, but they chose a different path.) 
BUT, I don't use my phone for serious listening. I have a dedicated AMP/DAC and my T1 for that. My point is: If your FIRST worry is SQ, then wired is the obvious way to go. That doesn't mean forget about SQ when it comes to wireless.
PS: mp3 is a well studied and documented lossy file format. With wireless, there is a on-the -go decoding going on which is a totally different thing. FLAC over bluetooth = 320kb/s mp3 is a claim that I cannot accept. 

 

[Fandesic]

Hi,
I have a question which needs your help : Why do you prefer the XB10 since you do write that the AT has a better wider soundstage ??? It is really not clear for me and I did read 2 times your review. Thank's in advance.

 

[The Walrus]

  Hi,
I have a question which needs your help : Why do you prefer the XB10 since you do write that the AT has a better wider soundstage ??? It is really not clear for me and I did read 2 times your review. Thank's in advance.

Soundstage? Neither DACs nor AMPs has any effect on soundstage. 

 

[Fandesic]

Here it goes.

Sources: LG G3, Samsung Galaxy S6 Edge + (both Apt-X capable) + Neutron Player, tracks: FLAC and MP3 320kbps, some 128kbps files and mkv movies in Archos.

Devices to compare:
AudioTechnica AT-PHA50BT, AudioQuest Dragonfly Red and Chord Mojo (last two just for fun).

Headphones: IE800.


Build quality vs AT
More or less the same, with slight edge for AudioTechnica - black and silver are looking more elegant. The clip on XB seems to be better but as I've found this morning its more or less as useless as one found in AT. Good clip should be working like the ones on Samsung devices (Link Level) or Soundblaster E3. Looks like I'll have to use some self adhesive velcro on the back of the XB10 same as I used on AudioTechnica. XB10 is a tad bit heavier - we'll see if that means better battery life.

Interface vs AT

As I've already found out the buttons placing is at least strange. IMHO the next/prev buttons should be placed on faceplate along with the volume controls. Placing them on the side and volumne on the front is not very handy. Also, volume control using buttons instead some rotary element is in my opinion not the best idea. In general, AT wins the interface part hands down, there is no way to press something by accident and if you intend to press something on purpose you can do this without looking at the device. I have big hands and I always have to look at the XB10 to see if I'm changing volume or pausing track. But if your fingers are smaller or I don't know, more "sensitive" - YMMV.

SQ
Bass: deep bass going strong and smooth to the sub level, really enyojable with IE800. No muddy midbass here, everything is audible and hummmms! (I'm a kind of basshead myself)
Mids: clear but a little distant, nothing good or bad to write here. Which should be taken as a kind of compliment really as there is nothing wrong with them.
Treble: clear, strong but without siblance - just the way I like them
Dynamics: good range, everything sounds engaging - no flat, dull tracks with this device.
Soundstage: OK. Not congested, not very wide. If I'd be forced to choose I'd say it is a little bit on the small side. Acceptable for my taste but I think that just barely. Definetely wider than the soundstage of Soundblaster E3 which was way to small for me to enjoy my music.
Others: No hiss whatsoever with 24ohms IE800 (them being very sensitive). Clear, black and empty background. Maximum volume levels with IE800 are ok, the max value is over my tolerance level but I was expecting it to be even higher. I will do some more testing here because I'm surprised that though they surpass my comfort zone I think that they still should be louder.


SQ vs AT
Bass: XB goes a tad bit lower than AT. Small difference but noticeable if your headphones are up to it.
Mids: AT mids, vocals especially, are closer and a bit more engaging.
Treble: more or less the same with slight edge to XB10
Dynamics: XB10 has more foot tapping effect, AT sometimes can get lost in congested parts of the track.
Soundstage: this one goes to the AT. This device has very, very wide soundstage, almost as wide as DACs like DragonFly or even Mojo. A winner here.
Others: AT hisses, just barely noticeable, on IE800. On IE8 hissing had to be supressed by 30ohm impedance adaptor. AT is also louder than XB10. Display - AT has a nice one, though I've never really used it. More like a eye catcher for strangers when commuting.




What I did not test:
balanced output, battery life (yet to be determined), BT range (as I wear the device on me when my phone is in my pocket), pairing with two devices (I dont expect any trouble here, as this is something that my 2009 mono HM1200 handles well)


Price:
AT-PHA50BT can be purchased on Amazon for ~100$ (new, unopened etc) while XB10 is available for 189$ (I will not comment on some amazon 240$ offers)
I think that if you already have AudioTechnica you may think twice about upgrading it as it has outstanding price to value ratio.
If you think about buying some portable headphone amp, consider Dragonfly Red - for almost the same price DragonFly's SQ is ubeatable, however, it is not wireless - but almost as portable as XB10.

But if you - like me - see that this kind of device is a must have, just try before you buy because like me you may end up with one in your pocket

I'm sure I forgot to write about a lot of things as this is my first try at a structured review - so feel free to ask me anything.

Hi, K4syx,
you say "Soundstage: this one goes to the AT. This device has very, very wide soundstage, almost as wide as DACs like DragonFly or even Mojo. A winner here." And after you say that you prefer the XB10. I Am lost! Can you explain why you prefer the XB10 over the AT please ?

 

[gr8soundz]

  Soundstage? Neither DACs nor AMPs has any effect on soundstage. 

 
Why would you say this?
 
Of course DACs and amps can affect soundstage. DACs maybe less so compared to amps but both certainly impact it.

 

[k4syx]

Hi,
I have a question which needs your help : Why do you prefer the XB10 since you do write that the AT has a better wider soundstage ??? It is really not clear for me and I did read 2 times your review. Thank's in advance.

Though AT IMHO had a better soundstage, every other aspect is better with XB10. Which still had soundstage good enough to my ears and that means that overall for me this is a better sounding device.

I hope this answers your question.

What I've learned since my original review is that XB10 is able to power nicely my modded AKG K7XX and stock Beoplay H6 Gen2. While the latter is to be expected as H6's are easily powered and good scaling headphones, AKG's require a lot of power from the source to make them shine.

And they do shine with XB10. This is a really good pairing IMHO.

 

[k4syx]

The purpose of this little device is convenience. If you are really interested in sound quality, you should know that you cannot achieve loseless streaming with bluetooth (At least not for now.) 

If your priority is sq, then plug your headphone directly to the source or buy a wired dac/amp.(Unless you have an iPhone 7. Then again, if you want to listen to music on your phone; why did you buy iPhone 7 in the first place?)

BTW since I am visiting the thread already

It's not only about convenience. Of course, wired connection will be better sounding (at least for now, though technology tends to get better over time), but only if the device that your wired connection is made to has a quality headphone amp section. And this means that though Apt-X is lossy, XB10 with this codec sounds way, way above any direct phone output that I've heard.
And I've heard all noteworthy of them (since that is one of my criteria when choosing a new mobile) since my trusty Nokia 5510.
That's kinda of topic but the best ones till now were LG G3 and HTC One S. I've yet have to hear new LG devices and S8 but that's a bit ahead of me with my S7E.

The point is that while wired, dedicated DAC/AMP stuff like Mojo or Dragonfly are of course superior, XB10 sounds better than direct wired connection to any mobile/notebook that I've heard while keeping the cost in line.

Well, another long one

 

[Fandesic]

Though AT IMHO had a better soundstage, every other aspect is better with XB10. Which still had soundstage good enough to my ears and that means that overall for me this is a better sounding device.

I hope this answers your question.

What I've learned since my original review is that XB10 is able to power nicely my modded AKG K7XX and stock Beoplay H6 Gen2. While the latter is to be expected as H6's are easily powered and good scaling headphones, AKG's require a lot of power from the source to make them shine.

And they do shine with XB10. This is a really good pairing IMHO.

Thanks, that does answer my question
Does any of you as compared the XB10 with the Arcam MiniBlink (as it can be used travelling with a usb battery attached!) ?

 

[The Walrus]

   
Why would you say this?
 
Of course DACs and amps can affect soundstage. DACs maybe less so compared to amps but both certainly impact it.

Not to open a can of worms here, but for an amp, you have your THD+N which should be as low as possible, your S/N ratio, the FR graph and the output power and impedance which should be well matched with your headphones. I'm guessing it's the non-linearity of FR in these little devices that audiophiles perceive as soundstage or whatever. Plug your headphones to any amp transparent enough to be called Hi-Fi and they all sound the same. The same goes for DACs. 
But, unfortunately 99% of the manufacturers will not disclose the accurate and complete specs of their products. Instead they rely on the subjective reviews in audiophile magazines, blogs, forums, etc. for marketing and advertising. This thing has deep bass that thing has wide soundstage mean nothing when you think about it. When you say deep bass, what frequency are you talking about and what dB? 

 

[gr8soundz]

  Plug your headphones to any amp transparent enough to be called Hi-Fi and they all sound the same. The same goes for DACs. 

 
Again, these types of incorrect statements make no sense?
 
More likely, some can't hear the slightest differences between DACs and amps but, rather than admit that, they incorrectly assume there are no differences and that no one else can hear the differences either.

 

[james444]

  Not to open a can of worms here, ...

  Again, these types of incorrect statements make no sense

 
Too late...

 

 

[The Walrus]

   
Again, these types of incorrect statements make no sense?
 
More likely, some can't hear the slightest differences between DACs and amps but, rather than admit that, they incorrectly assume there are no differences and that no one else can hear the differences either.

Did I understand you correctly? Are you saying that your ears can hear what the instruments we have in the year 2017 cannot measure? 

 

[gr8soundz]

This thread was supposed to be a discussion about the XB10 which can be described as a bluetooth dac/amp. If it's incapable of sounding any different from similar devices, why discuss it at all?
 
It's irresponsible to suggest that every manufacturer lists incorrect specs or that every manufacturer is lying about their dacs/amps not sounding exactly like everyone else's?
 
Shopping only by numbers and insisting that all audible differences must be measurable is ridiculous when each of us has different hearing (or are you saying that is wrong too?).

 

[The Walrus]

  This thread was supposed to be a discussion about the XB10 which can be described as a bluetooth dac/amp. If it's incapable of sounding any different from similar devices, why discuss it at all?
 
It's irresponsible to suggest that every manufacturer lists incorrect specs or that every manufacturer is lying about their dacs/amps not sounding exactly like everyone else's?
 
Shopping only by numbers and insisting that all audible differences must be measurable is ridiculous when each of us has different hearing (or are you saying that is wrong too?).

Look, I agree this thread is about XB10. But when I hear about soundstage associated with dac/amps over and over and over again, I go nuts! We know every parameter of electronics, we can measure them precisely. If you are plugging your headphone to two different devices that measure the same within 0.001% precision and you hear a difference, that is between your headphone and your ear, do not blame the electronic device or try to make up esoteric terms only discernible to audiophiles with  hyper-sensitive ears.
If you say the earth is flat because my hawk-eyes can say so, there's no point arguing.