[actorlife]

  Just sat down and listened to my AD8620 mod'ed X3, Nano 7G and DX50, volume matched to within 0.5dB of each other (it is impossible to match any closer since all three has digital volume control). Here are some quick impression:
 
Soundstage (wide -> close): DX50 > X3 > Nano 7G
Texture (thick -> thin): X3 > Nano 7G > DX50
Control / tightness: X3 > DX50 > Nano 7G
 
One thing that struck me early on is that DX50 sounds more gainy and bright than most DAP I have. The three way comparison really explains why - it is because DX50 is really thin on the mid and upper bass, which in effect emphasizes more on the treble in the overall presentation and makes it more edgy than it should. On the other hand, the slight hollowness also gives DX50 an excellent soundstage. IIRC, these are kind of opposite to what I have heard on the stock X3. I think I still prefer my mod'ed X3 the most. Though it is easy to tell that Nano 7G isn't quite as good as DX50, I think it actually has better balance as well. If only DX50 has a thicker mid, it would have been really great. Just wonder what opamp DX50 has on the headphone-out and maybe they are worth modding as well.

Hi ClieOS! Is there a thread on your mod for the X3? Edit found it. Thanks!

 

[ClieOS]

   
Is it possible that the DX50 doesn't use +/-4.5 though? I read somewhere that it uses a single ended 9v supply (which I guess implies use of voltage doubling circuit) , which is also why they used a high capacitance. If it does actually use a single 9v supply, does that change the 8620 and 797 being bad ideas, or is it still not good?

 
There is a few ways to tell. The first thing is of course DX50 uses a single nominal 3.7V smartphone battery that max out around 4.2V in full charge and drop to around 3.2V when it will cut itself off. This range of voltage means you will need a voltage pump / regulator circuit so it will constantly pump out a fix voltage you can use and no need to worry about instability. Then comes the problem that most opamp requires +/- voltage rail to work (some do take single rail, but they are less common in comparison). The way I see thins, either iBasso pump the voltage up to 9V then splits it to +/-4.5V, or they pump it to 4.5V first, then create a negative rail out of it. Neither are difficult to implement and using a single 9V will just be asking for trouble, so they is no reason why they didn't do it. The better thing will be to pump it up to 9V, then makes a negative rail of it, which gives you a combined 18V swing. However, pumping up voltage too much has its own problem so it is really not suitable for a compact DAP like DX50 with such a small battery to begin with. Remember music is in AC, so voltage needs to swing from positive to negative rail and back. Those opamp that accepts single rail usually has a built-in charge pump to pump their own negative rail, so in a sense it is still +/- voltage on the inside.
 
Like goodvibes said, those caps are for DC blocking and not related to power. But if the power section is done right, then you won't need big output caps since there won't be any DC offset. Using output caps is usually considered a compromise for not having a decent power section, which make sense on a DIY amp like cMoy but not on a DAP of size and price tag like DX50, unless it is done purposely to have the 'flavour'.
 
Anyway, a single 9V rail still won't work with AD8620 or AD797. Both require +/-5V minimum.

 

[goodvibes]

I thought from his comment that it had a 9v battery split to 4.5v rails. Sounds like the bump it up first and then split it as you described.

 

[ClieOS]

I would take a guess that he might have read it up from a certain Japanese blog about the 9V thingy. I saw it as well but they are referring to the +/-4.5V being similar to a 9V split in half, like a cmoy.

 

[GiantTree]

Hi, ClieOS,
AD8620 is much better OPAMP for my X3.Thank you for your suggestion.
The X3 is no longer muddy sounding after this mod.
Do you have other suggestion?

 

[ClieOS]

Do you have other suggestion?

 
On opamp? There are quite a few alternative mentioned in the X3 mod thread in the DIY sub-forum, check it out. Some has better current output than AD8620 so they are probably technically 'more correct' as a replacement. But if you are happy about the sound of AD8620 in X3 and didn't run into any trouble on output power, I don't think you will find a better sounding combination.

 

[GiantTree]

With the AD8620, the X3 sounds clean. With the original AD8397, it is too muddy. Some people said it is warm sounding, but I don't think so.
However, the AD8620 mod has a very flat soundstage, and lack of power.

I am going to check the mod thread. Thanks.

 

[kernel8888]

Any opinions or experience with either of these paired with a jh16? Like to power of the x3 but wonder if it would be too bassy for the jh16, and if thedx50 might be a better match for sq? Just want to retain as much clarity as I can in the jh16.

 

[howdy]

Any opinions or experience with either of these paired with a jh16? Like to power of the x3 but wonder if it would be too bassy for the jh16, and if thedx50 might be a better match for sq? Just want to retain as much clarity as I can in the jh16.

I'm not sure how the jh16s sound but if clarity and less bass is what you are looking for than I would get the DX50. Be prepared though as the DX50 still has some UI issues but they are getting better as updates still keep coming.

 

[t1m0k]

I used to have an iPod nano that I'd connect to my Grados through a FiiO E1 portable headphone amp, but I lost the amp and the iPod a few days ago. I loved the sound the FiiO gave me! Now I'm doubting between getting the iBasso or the FiiO. If anyone feels like giving me some advice that's relevant to my personal situation it'd be greatly appreciated! My knowledge on audio quality is limited and I usually base my decisions on what the majority of people on here suggest.

 

[davidsh]

Depends on your use and what you want. I like that the x3 can be used as a DAC/amp with my computer

 

[teaough]

Good luck if your DX50 arrives broken like mine did. $25 & two weeks to send the RMA back (usps intl.) to Hong Hong then waiting for the next batch from iBasso. Amazon & Parts Express for the X3 are WAY more convenient. The X3 is $50 less expensive. They have stock ready to ship, ship fast & free, and returns are WAY easier/cheaper.

My DX50 arrived broken. Getting permission for the RMA took 4 days of back/forth to China web-based problem ticket typing, it'll cost me more $80 more than the X3 after reshipping, 2 hours at the Post Office waiting in line, 3 weeks waiting for another unit (which may not work either), and the software will still be buggy.

I think I made the wrong decision.

 

[goodvibes]

I very much like that FiiO uses local distributors. When I tried a couple of their products in the past I ordered from the US where I reside. 

 

[t1m0k]

Being able to use the X3 as a DAC is pretty sweet but I don't really need that functionality. The fact that FiiO has US distributors has no added value to me as I'm not from there, I bought my previous FiiO when I was visiting...
 
I consider my Grados to sound a bit cold and liked the warmth the FiiO amplifier gave me. How does the iBasso perform in this aspect? I like the design and UI of the iBasso better, but if the sound doesn't match with my headphones I should probably go for the X3.

 

[DrGonzo]

How does battery life compare between the DX50 and X3?