Originally Posted by ozkan
Yes, an amp at $200-300 price range will change the SQ of M10 dramatically. Believe me because the dac itself is so good and clear sounding. Even a C&C BH2 is way better than M10's built in amp. If you can pair it with O2 or Headstage 4G, you can be shocked at how it sounds.
I vigorously agree!
The headphone amp of the PCM-M10, in my opinion, rates no better than a 3 on the 10 scale of what is possible with headphone amps, but the PCM-M10's proprietary 96/24-capable sigma-delta DAC rates at least 9 on the 10 scale of portable DACs. The PCM-M10's Line Out is the best kept secret in all of Head-Fi. You can tell people about it until you are blue in the face, but they figure any device that can be purchased for $200 can't possibly compete with an $800 HiFiMan HM-801 Line Out, for example, with its legendary cult-worshipped, dual mono PCM1704U-K DACs. Assumptions are made based soley on price differences. They need to listen to the PCM-M10 Line Out.
Of course, the more efficient the IEM or headphone used, the less noticeable will be the benefits of a more powerful headphone amplifier, but even with moderately efficient headphones like the Sennheiser Amperior, there's a big difference in dynamics, bass control and extension to be had with an amp like the Meier Corda Stepdance, 2Stepdance, Quickstep.
Your earlier post, above, regarding the use of an external battery for the PCM-M10, makes sense to me, even though I've never tried it. If the voltage is even a little bit higher (be careful), the headphone amp will have greater swing, and even if the voltage is identical to that of internal AA batteries, the ability of various Lithium chemistries to deliver higher levels of current when demanded could explain the improvements you hear with the PCM-M10's headphone amp. But, as you say, the improvements had with this can only be subtle.
I've spent a lot of time in the past week A/B testing the PCM-M10 Line Out vs. the HiFiMan HM-801 Line Out, into various amps (Meier Stepdance, iBasso PB2, DACmini CX, TBI Millenia MG3, and Emotiva Mini-X a-100). All into my favorite headphone - Audeze LCD-2.
Using a FiiO HS2 switchbox that allows me to just turn a knob to go back and forth between the PCM-M10 and HM-801 Line Outs, while both sources are playing the same track, started simultaneously to get them synchronized, I've concluded that, in terms of sound quality alone, the HM-801 is offering me only two subtle advantages and only two subtle disadvantages vs. the PCM-M10 sound quality: The HM-801 Line Out offers just a little bit more detail and separation, most noticeable in congested tracks where a lot is happening that has to be sorted out by the DAC, and not noticeable at all in simpler tracks, such as acoustic guitar solos. On the down side, the HM-801 Line Out is less neutral and less balanced in frequency response than the PCM-M10. When I told a friend of mine about this lack of smoothness in the HM-801's frequency response, he pointed me to a review by Mike at Headfonia, where he had observed the same thing.
Quoting Headfonia comparison of HM-602 and HM-801:
As a result of the treble extension, there is more sibilance on the HM-801 than on the HM-602. I also find vocals to have better presence on the 602 than on the 801. Moreover, while the additional bass weight and low bass is welcome, the transition from midrange to bass is actually smoother and more linear on the 602. I think overall the 602 has a more likeable sound signature, while the technicalities are still a little short from the bigger brother.
It's subtle, not really a problem, but not as nice as the more more neutral and flat frequency response of the PCM-M10 Line Out, for sure.
These pros and cons are hair-splitting. They are both 9 out of 10 for portable DAC quality, in my opinion (leaving 10 for some portable DAC I've not yet heard). I'm really left with no reason to keep the HM-801. I'll be returning it under their 30-day return policy. I can make that decision on sound quality alone, ignoring the huge price difference AND the outrageous differences in build quality, ergonomics, cosmetic appeal, user interface, firmware quality, and battery life - for which the PCM-M10 completely blows the HM-801 out of the water on all counts. And all for 1/4th the price. The HM-801 only comes close to competing with the PCM-M10 in sound quality.
At everything else, it's a big FAIL, in my opinion - especially with its deplorable firmware. I intentionally waited until the HM-801 was replaced (with the HM-901) before buying it, just so that I could get the last firmware revision - to avoid all the bugs that early adopters have had to suffer. Well, even with the v.0.23 firmware, using the HM-801 is like learning the path through a minefield - avoid this and it will work - avoid that and it will work. In contrast, the bug-free PCM-M10 is a complete pleasure to use. Yes, it has none of the typical features of most DAPs (had with even a Sanza Clip+), as it was designed to be a recorder, not a DAP, but in the end, its interface is much friendlier than that of the HM-801. And if you're using it as a Line Out to an external amp, the 30 hours of play on a pair of AA's beats six hours of play from the HM-801 by a factor of five! And while I'm beating up on the HM-801, let me add that its rechargeable LiPo battery costs $80.00 to replace, but it's bound to go out of production eventually, just as the HM-801 itself has. And let's not forget the size and weight differences - especially when you consider carrying four extra batteries for the HM-801, at an additional cost of $320, to achieve 30 hours of portable play.
The portable card reader to Line Out winner is: The Sony PCM-M10!
Edited by zilch0md - 9/14/13 at 7:29pm