The tremendous growth of the portable audio industry has brought us tons of new amplifiers, each with their own claim of a superior sonic quality. It gets up to the point where we become wary of manufacturers claims, as power ratings and “special” technologies implemented in the design of the amplifier are rarely a guarantee of good sound. Among this sea of products, I have to sort of do a curator’s job, selecting which products actually have the sonic quality to be presented to the readers.
When I first came across this generic looking portable amp from the manufacturer by the name of Soundmagic, honestly I didn’t think much of it. “Just another plastic portable amplifier in the sea of chinese made amplifiers flooding the market”, I thought. We’re all guilty of that sort of pre-judgment once in a while, but what matters is to be willing to admit our mistake and confess objectively if a product has truly delivered the goods.
If you’re used to the build quality of Ray Samuels Amps, then you’ll probably look down at the build quality of the Soundmagic A-10. Fully enclosed in a molded plastic rubber housing, the overall housing quality feels sub par to the Fiio E11 or the E7. And yet, the A-10 actually earns a serious enough sound quality mark that it may earn a permanent place in my portable amplifier recommendation list. So, this thing actually sounds good, and enough to give me some highly musical moments, even with the highly scrutinizing Sennheiser HD800 headphone.
The overall sound signature is warm, dark, with full mids and lows. In a way that sounds like a description of RSA portable amps, only the A-10 tend to be slightly looser in the bass and mids. The slightly loose bass, however, doesn’t take away from the fact that the A-10 is highly musical, and even more musical than some of the RSA amps I’ve reviewed in the Usual Suspects review (please don’t ask me which specific model though). And again, though the bass is looser than say the Fiio E11 (and likewise the maximum power output is much lower than the E11), the overall musicality of the A-10 is higher than the E11 and matches the smooth sounding JDSLabs Cmoy, which has been my #1 favorite sub $100 amp for a while now. The E11 on the other hand sounds dryer especially on the mids and bass, where the A-10 can be so liquid it sorts of reminds me of a hybrid tube amp design like the Hifiman EF-5 amplifier.
Compared to the JDSLabs Cmoy, the A-10 is slighly less refined and is less smooth. But tonally, I prefer the A-10’s balance as you get more body in the lows, compared to the more mid centric JDSLabs. And what an amazing discover it was when I found out that despite having a slightly narrower soundstage than the JDSLabs, the A-10 has a far deeper soundstage than not only the JDSLabs, but also the amplifier section of $799 Fostex HP-P1! The Fostex is an excellent portable DAC/Amp box, so this is not a bash to the Fostex, but rather a testimony of how well the A-10 scores. With that deep soundstage, combined with the Fostex HP-P1’s D/A conversion, playing some live piano recital by Horowitz out to the Senn HD800 gave me some of the most musical moments I’ve ever heard from a portable set up. The A-10 may not look like much, but the sound is among the musical I’ve heard in portable amps.
The A-10, however, is not without flaws. While I enjoy the sound of the A-10 very much with the JH16Pro, the level of channel imbalance in low volume levels is so bad that I am stuck to a single spot in the volume level where I can get a clean left/right channel tracking. The A-10 definitely wins the award for the worst volume pot I’ve ever encountered in a portable amp, and in that sense I wouldn’t be recommending this amp to IEM users. The level of volume gain is also a bit limited, quite a bit higher than the standard Ipod headphone out, but still lesser than many other portable amps, and definitely out of league when compared to the Fiio E11’s maximum power output (which drives the Hifiman HE-500 so successfully over and over again). So in this sense the A-10 should be limited to fairly easy to drive portable headphones, like the Sennheiser HD25-1, Audio Technica M-50, Fostex TH-7B and T50RP, and other similar headphones in that range. The USB recharging feature is very welcome, but not so welcome is the design of the volume control where the knob never stays still when you put the amp in your jeans pocket.
When I switch gear to a more aggressive music like Muse and out to the Sennheiser HD25-1, the additional bass I get from the Soundmagic A-10 is so much, I actually think it’s a little excessive. The bass section is not as articulate as some of the more expensive amps, and as I’ve mentioned, the bass section on the A-10 is a bit loose. But when I say excessive with the HD25-1 and Muse combination, it’s actually not the boomy kind of excessive bass. Rather, it’s a bit excessive on the punch area, which is the kind of excessive bass I like. Surprisingly the additional bass comes already with the bass boost switch off. Turning on the bass boost gives me a very slight boost on the lower bass, but really not that significant depending on the recording, unlike the Fiio’s or the JDSLabs’ bass boost. Not a big deal, in my opinion, as the A-10 already comes with its own “bass boost” even without the boost switched on.
The volume control flaws and the limited amount of voltage swing will definitely get in the way for the A-10 to earn a serious recommendation from me. Although I think that it would be fairly easy for Soundmagic to release an updated A-10 with an improved voltage swing level for higher level of loudness, as well as replacing the volume control design with something better. At the moment though, ignoring those shortcomings in the design, I’m really in love with the A-10’s sound quality. If you evaluate it on a score basis, it’s probably going to get beaten on every category by some of the $300+ portable amps. But when you forget about the scores and simply listen to some good music to it, the A-10 suddenly becomes a very solid performing amp. The JDSLabs was a very strong favorite sub $100 amp for me, but this time I think the A-10 is giving it a real competition in terms of overall musicality. Oh, and last, I think I need to mention the cool fact that the A-10 turns itself on only when you have a headphone plugged in to its output, something that I would definitely love to see on higher end amps.
Gears used for review:
Headphones: Sennheiser HD800, HD25-1, Audio Technica M-50, Fostex T50RP, JH16Pro
Amplifiers: Soundmagic A-10, Fostex HP-P1, JDSLabs Cmoy, Fiio E11.
Source: Ipod Classic, Fostex HP-P1