Please be easy on me since this is my first post although I've been a lurker for years.
I had the good fortune (misfortune?) of sampling some audio gear over the recent months (JHA JH5, HiFiMAN HE-400, Fiio X3, and most recently JDS Labs Objective 2).
For all of us who have been craving a decent Amp/DAC/DAP under $200, the X3 was an incredible boon (anticipating the X5 coming up soon!). However, I was unsure if I was getting the most out of the orthodynamic HE-400 from the X3 so I was itching to upgrade the amp. I also wanted to make sure the amp would be suitable for IEM- yes, amping an IEM like JH5 is a worthwhile endeavor. I was considering the Magni for a really long time but ultimately ended up with the classic O2 after being inspired by this article in IEEE Spectrum about NwAvGuy's mysterious disappearance. Also, for what it's worth, I really appreciate the small time "Made in America" companies like, Jerry Harvey Audio, Schiit and JDS Labs. Also, a huge fan of HiFiMAN and Fiio for being innovative and affordable.
Anyways, here's the testing set up:
Spotify 320kbs (I know, it's not FLAC, but it's convenient and affordable- read: realistic for my everyday use) -->
Macbook Pro Retina -->
X3 via monoprice gold-plated ~24" USB and
O2 via ~3" Fiio 3.5mm cable
--> HE-400 and JH5
To build upon prior evaluations, I can save you some time and just address these two helpful comments:
1: Does X3 need amping?
ClieOS: "One last question to answer: Does X3 needs amping? To put it short and sweet, no…well, mostly. There is very little to gain (and even positively lose) in sound quality by amping the X3. Unless we are talking the top of the line (ToTL) portable amps here, say O2, JDS Labs C5, FiiO own E12, UHA-4, etc , otherwise the benefit of amping is simply not there. The internal amp of X3 can rival the SQ of just about any mid to upper-mid range portable amp. The basic design of X3’s DAC and amp section come from E17 Alpen. But FiiO pumps the voltage up a little more on the X3 so the overall SQ is actually better than E17, most noticeably in overall dynamic and cleanness of the sound, given that X3 doesn’t have to deal with any possibility of USB noise, jitters, or ground loop. But even with the ToTL portable amps, the increase of SQ just isn’t night and day. So whether it is worth carrying another piece of gear is really a question of whether you will find the improvement substantial enough in your own rig. In my own opinion, X3 is already an excellent all-in-one solution."
According to my listening notes, "The X3 + O2 sounds BOSS." They "complete" each other (more on this below). Separately they sound pretty similar and the individual sounds of the X3 or the O2 isn't improved enough with the combo for me to recommend anyone buying both devices for this purpose. As far as amps go, I've only personally listened to E17/X3/O2 so I can't give an opinion about another, in ClieOS's words, ToTL amp. For my amp/dac solution, I did not want to spend more than $200. So I would have to choose between X3 alone or O2 alone.
2: O2 vs. E17
Steve Guttenberg: "compared the 02 with my FiiO E17 headphone amp, and felt both amps are really good, but the 02 wins on clarity, dynamic punch, and bass precision. Voices also have more "body" and sound more natural over the 02. In that sense the 02 sounds almost like a vacuum tube amplifier, but without sacrificing bass articulation."
In my personal experience with E17 vs. X3. The X3 pretty much sounds like an E17 that can play music with a lower resolution screen and less control over bass, treble.
The X3 produces a clean beautiful sound that sounds a bit more "cool" and clear than the X3. Still very good. I was really impressed with the X3's very low noise floor (read: silent). It's also really appealing to not have to worry about any cables (read: $$$) if I used it purely as a DAP.
The O2 did not sound as clear as the X3 (could be due to the lack of another DAC in my setup) but it provided a lively, more full bodied sound with a wider sound stage and better instrument separation. I'm inclined not to worry about a DAC per Ken Rockwell's analysis.
As mentioned above, you can understand how these would complete each other and result in a sound that I could only describe as BOSS. The natural full bodied sound of the O2 melded well with the X3's clean sound. It wasn't excessively bassy or the treble wasn't too high. I found it pretty well balanced. But I can live without the balance to meet my price point.
FYI, here are some of the songs I used for sampling:
AC/DC - Back In Black
Katy Perry - Dark Horse
Macklemore - Thrift Shop
Daft Punk - Lose Yourself to Dance
Norah Jones - Don't Know Why
Coldplay - Magic
The O2 and X3 are like choosing between champions. The X3 is more compact (read: pocket size) and offers better features. The O2 produces a slightly more natural, full bodied sound that I prefer. The O2 is cheaper than the X3 and is much more likely to hold up its resale value in the near future (Fiio's X5, although not an exact replacement of the X3, is coming to the US soon). It's definitely a close match-up but I will probably keep the O2.
Thanks for reading :)