The JDSLabs Cmoy is one of the strongest entry in the sub $100 amps range, and one of the main reason that motivates me to start up this comparison. The Cmoy name is perhaps the most popular name in the portable amp world (anything else comes close?). The design of the Cmoy is also the simplest design I’ve encountered in the portable amp world (again nothing else comes close). What I’ve witnessed across different portable, desktop, and speaker amp designs is that simpler designs would normally excel in musicality, midrange quality, and coherence while complex design would excel in technicalities and top and bottom extension. This seems to be the same case with the JDSLabs Cmoy. Most striking is how musical and smooth the overall sound signature is from the JDSLabs. I actually used the Sennheiser HD800 a few times during the JDSLabs Cmoy and found the sound to be totally smooth from top to bottom (any distortions and artifacts in the sound would’ve been very noticeable through the HD800). A very surprising performance from a $60 amp, seeing that many more expensive amps sometimes exhibit artifacts in the sound.
The frequency balance is mildly mid-centric, and the midrange is also wonderfully smooth and sweet. The JDSLabs is definitely ranked #1 for midrange quality among all the amps in this shootout. Though being mid-centric, you don’t get a constricted sound that you often hear on other midrange centric sound. The sound is still very open and spacious – actually the most spacious in this shootout along with the AMB Mini3. The soundstage not only have a good width, but also good depth. This is perhaps the second best aspect of the JDSLabs, and you should not underestimate the soundstage of this $60 amplifier.
The overall presentation is mildly laid back and warm. It’s a nice midway between bright and dark sounding, with a fairly good PRaT factor. The bass plays at the mid bass and it delivers a fairly punchy and smooth midbass, though turning on the bass boost brings the bass section up considerably, also helping to add some more body on the low bass. The bass boost does reduce the naturalness and does sound like an intentional EQ-ing on the sound, and so most of the time I’m content to live with the JDSLabs’ non-boosted bass.
Other nice features is semi automatic on/off on the amp. The volume pot includes a built in power toggle switch, but even when the volume is on, the amp will remain to be off if there is no headphone plugged in. Hence the amplifer will automatically turns itself off when you unplug the headphone. The op-amp is socketed and so you can experiment with op-amp rolling, though I’ve found the stock OPA2227 to be best in my opinion, better than even the OPA627. There is also a socket for DC power, and with a simple 12V DC power you can use this amp as a simple desktop set up with no fear of battery life (stock battery life is very good though–I didn’t count but it just went on and on for days). Driving the JDSLabs Cmoy from a 12V DC laptop power supply also improved the dynamic range of the amplifier — an option that I wholly recommend.
I realize some people may not be too happy with the Altoids case, and I do question its durability over long periods of use. I myself has been babying my JDSLabs Cmoy so I can’t tell you how durable the Altoids tin case is. Other than that, the build quality is very good. John uses high quality 3.5mm connectors, as well as volume pot and knob. Worth mentioning is also the ability to customize each build. You can tell John what IEM/headphones you’ll be using with the Cmoy and he can lower/raise the gain accordingly. The stock gain of 8 is quite good for everything except the most demanding full size or the super sensitive IEMs. Lastly, though my amp doesn’t come with a recharging circuit, you can also ask John to build your amp with a recharging circuit. That should improve day to day usability a great deal.
FIIO E11 (and E7 briefly)
The Fiio E11 is the newest addition to the Fiio line up. Designed around a three channel, active ground design and powered by a user-replaceable cellphone battery, the E11 along with the Soundmagic A-10 are the two smallest amps in this shootout. Between the E11 and the Soundmagic A-10, the E11’s build quality is definitely better, though I must confess that I find the Soundmagic’s sound signature being smoother and more pleasing overall. Over the course of this review, however, I’ve grown to like the E11 more and more. The A-10, on the other hand, was not that pleasing for day to day use (more on that later).
More than anything else, the thing that impresses me the most about the E11 is its ability to drive the Hifiman HE-500 without sounding anything like a small portable amp, let alone being powered by a measly 3.7V cellphone battery. Other than that, when paired with more revealing dynamics, the E11’s dark sound signature lacks the smoothness and refinement that I’m getting from the other amplifiers in this shootout. This is what I wrote on the Fiio E11 article:
I also compared the E11 to the JDSLabs Cmoy (stock configuration) and found the JDSLabs to sound significantly bigger and grander, both in the soundstage and the overall sound presentation. The JDSLabs also had a smoother sound throughout the frequency range and is clearly my favorite of the bunch, except when I need to drive the monstrous HE-500 headphone, in which the E11 is the only one that can do the job. Many amp builders swear by the quality of through the hole parts when compared to SMD ones, and in this case I think it’s what’s contributing to the overall bigger and smoother sound of the JDSLabs, despite being based on a much simpler design when compared to the E11′s three-channel design. I was quite unenthusiastic about the E11 when I begin this shootout. During the course of this review, however, I started to realize that my perception has changed a little. In the beginning, the JDSLabs carried a lot of weight as I find it (and still is) to have a very pleasing and musical sound signature. On the other hand, the Fiio E11 was the least smooth sounding of the bunch, and was my least favorite amplifier of the bunch. However, as I used the amplifiers day to day, I begin to realize that when the set up is not as picky and the music is not as demanding, the Fiio E11 would easily come on top of the Soundmagic amp as the A-10 was really difficult to live simply due to the volume control that keeps on getting moved accidentally. It doesn’t change the fact that I feel the E11 to have the least smooth mids of the bunch and the least refined of the bunch. But overlooking the slightly dry midrange, the sound signature is quite fun with a good punching bass and so I didn’t have problems enjoying the sound of the Fiio with less demanding music (i.e pop or alternative rock recordings that don’t have a good recording to begin with). And while the JDSLabs clearly have the more refined sound, I know that in portable situations many would put a greater weight on the Fiio’s more compact dimension.
By default, the E11’s bass is quite punchy, though turning on the bass boost adds even more bass into the mix. This amp is definitely good if you’re a basshead, and the best at that among the other amplifiers. The E11 is not about refinement, midrange, or technicalities, but is rather focused on bass. If you ignore the lack of refinement a little, the sound is actually a lot of fun. The treble is just enough, the mid body quite good, and the bass is punchy and fun. On less demanding recordings (say pop, rap, alternative rock), I think the E11 is a very fun sounding amp, with the best packaging and features among the other amps in this comparison.
On the E11 article, I made a comparison between the E11 to the E7. I said that the E7 and the E11’s amplifier are mostly similar in technicalities other than a difference in sound signature — the E7 having more treble and is livelier and more open sounding. However, after spending more time with them, the E11 does come out as the more musical amp of the two, albeit by a small margin. The E7’s power swing is also quite limited compared to the E11’s. So if you’re only looking for an amp, definitely go with the E11.
Continue to the next page…