First Impressions:
Buggering hell. Nobody left a note on the door for the postman. Looks like I probably won’t get my E11 until tomor- OH YES IT’S HERE. THANK YOU MISTER POSTMAN.
I think this is what we refer to in the the trade as 'double prizes'. My amp and battery come strapped together in the post.
Opening up the package, it’s small. Very small. I don’t have much experience with portable amps, but I’ve seen and heard a few in person (including the Headstage Arrow 4G) and this is still pretty tiny, at least in terms of footprint. The metal box is a very nice touch, showing off just the unit as you open in, iDevice-style. In fact, it’s taking a few cues from iDevices in terms of design, most notably taking cues from Apple’s iPhone 4. All the buttons seem to be clicking, all the accessories seem to be present – let’s juice it up and see if pretty sounds come out of it.
The E11's classy little metal box. I like the wireframes you get on FiiO packaging.
The knob takes some twisting to switch it on – hopefully this will become less stiff over time (though not too much so). The pot action itself is also little stiff, which is a problem when the unit is lying on an iPod, though not so much when you can get two fingers on it. If you have fingers of steel you’ll get that attractive blue LED and maybe some music.
Sound-wise, there’s quite a bit of bass, even without any EQ. I quite like bass, but listening to a number of bassier tracks with MS-1s it gets too much quite quickly on anything except EQ (bass boost) of 0. Treble is clear but perhaps a bit grainy; midrange is there but not prominent.
Ooh, shiny. Figuratively of course; the finish is matte.
Build/design:
The unit is small and light, the same footprint as a credit card and about 1.3cm thick. The main construction is of silver plastic, with the two panels made of fairly thin black anodised aluminium. The overall heft is a bit lacking, requiring perhaps just a bit more weight to have a truly solid feeling in the hand.
The whole thing looks very classy, the white on black printing contrasting with the silver of the main body. Even the blue power and red charging LEDs are the perfect intensity, such that they’re visible in direct sunlight but not blinding in the dark. If you’re one of those audiophiles who likes your rig to look good, the E11 certainly beats out a lot of the (much) higher-priced competition aesthetically.
A number of accessories come packed in: a short and flexible 3.5mm-3.5mm right angled cable, a short USB cable and a patented FiiO audio-class rubber band for keeping your rig together. All are pretty well made and have been useful – there are no useless frills in this package.
Here we have the solid silver IC, the rhodium-plated, deep-fried platinum USB cable and the supercolliding superband
One of the E11’s more individual features is its enclosed volume knob. One feature that’s always put me off some amps like Headstage’s Arrow is the use of a wheel as a volume control – though I understand that it’s a good way to have a very thin but tactile control, it reminds me of a cheap portable radio and is still somewhat prone to being caught on things. The E11 takes something of a halfway-house approach with its design, combining aspects of both a wheel and a proper knob.
In theory I love this idea, but in execution it does have some caveats; first being that the switched ALPS RK097 is very stiff to use and the small size of the knob means that there’s not a lot of leverage to help you here, even with the nicely machined knurled aluminium knob. It’s especially difficult with the built-in on/off switch, which needs a good bit of force but has a good ‘thunk’ to it. One upshot of this – the chance of accidentally changing the volume is almost zero. This is not nearly such a problem if you can have your E11 so that you can get your finger and thumb around the knob, though.
On a more positive note, a multimeter shows that the pot tracks very well, with no channel imbalance above 1/8 on the volume dial (you need to go past about 0.75/8 for the amp to switch on) and I have verified this with my ears. Note that if you’re using anything even vaguely sensitive with the E11, you will have to be very fine in your volume adjustments, as the gap between too quiet and uncomfortably loud is not great, even on low gain. In fact, the loudness on this unit has me thinking of a custom iPod LOD with input resistors to attenuate the signal a bit and give me more room to manoeuvre on the pot.
Switches are small, plastic and clicky. They don’t feel either particularly solid or cheap, but they do a good job. I do sometimes find it hard to select the middle bass boost setting one-handed, though.
Moi? Take a picture in bad light because I just want to post this damn review and be done? Never. The internals, btw.
The sockets grip a 3.5mm jack well, but lack the satisfying mechanical click you get with more expensive Neutrik connectors and the like. They’re fine for now, but I worry that they may become looser over time as jacks like this are prone to. They’re also perhaps a little close together, though I’ve had no problems so far. On a side note, pulling out the multimeter again showed that the DC offset of the amp was consistently <1mV, which is good news all round.
EDIT: It seems like the 3.5mm sockets have one extra bonus - if you own a HiFiMAN headphone with a TRRS balanced plug, they will give you proper stereo sound without the use of an adapter. So useful if you need it, no negative if you don't.
Another more original feature of the E11 is the ability to easily change the battery, accessed by the removal of the bottom panel of the amp. Removing the panel is a bit stiff the first few times you do it, but there is a knack to it. Once you have that down, changing the battery is a breeze and also gives you the opportunity to ogle the ‘power’ switch. The E11 utilises the AD8397 opamp which can be run at two different current levels that provide different balances between sound quality and battery life. Changing between the two modes is controlled by a small dip switch under the battery.
As expected of a mass-produced product at this price, there are a couple of minor imperfections and blemishes: moulding lines on the plastic frame are obvious, there are some small scuffs on the corners of the faceplates and the knob protector doesn’t quite sit flush with the frame. None of these really detract from the overall look or usability of the unit, though.
Battery Life:
In my tests the battery life easily exceeds the 10 hours marked out for the standard battery on high-current mode. However, much of my listening has been with a 1550mAh battery from fleaBay, which lasted at least 15 hours on the first charge and hasn’t managed to run out its second charge yet after over a week of intermittent use, mostly with Alessandro MS-1s (Edit: ran out whilst writing the ‘sound’ part of the review. Around 18-20 hours, I think.)
My third-party battery. Not really relevant, but it's a nice shot. I got this one because I liked the colour, I'll be honest.
The E11 charges from a normal mini USB input, which though possibly confusing to those who decide that it’s also a DAC (NB: it’s not) is a very good design choice from FiiO. Unlike wall plugs, USB is standard around the world – that means sockets, cables, voltages, everything. The E11 charges perfectly fine from both a computer USB port and an AC adapter like those that come with iPhones and Kindles, etc. Since we actually have two iPhones and two Kindles in our household (none of them mine) I’ve ‘borrowed’ one of these adapters on a semi-permanent basis for E11 duties. If any prospective or established portable amp designer should take any lesson away from FiiO’s latest, it should be this: MINI USB IS GOOD. WALLWARTS AND SPECIFICALLY-SIZED BARREL CONNECTORS SUCK.
Although the E11 does have a long battery life, it does have one problem in that you don’t know when it’s low on juice. The unit just dies, which can be quite disconcerting the first time it happens. A feature such as the power light changing colour when the battery falls below a certain voltage would be reasonably easy to implement and very useful. As it is, the best idea is probably just to keep the unit juiced up by charging whenever possible. Note that due to the three-channel design used in the amp circuit, the unit is switched off and cannot be used whilst charging (Virtual ground comes in to contact with actual ground, apocalypse ensues if current passes across them. Do not cross the streams!) This is a mild annoyance for me at best, as I have two batteries and since changing them on the fly is easy, I’m never without an amp for more than thirty seconds. A couple of quid/bucks/rupees spent on an extra battery is easily a good investment here.
Sound:
The unit was subjected to my usual burn-in regime of no burn-in at all, because it’s all a lie, caps form near instantly and any change is all in your head. What I did do is spend a lot of time acclimatising to the sound of the amp and letting my brain equalise to its tonality, which is far more important in this reviewer’s humble opinion. If my lack of burn-in offends you, be aware that at the time of impressions the amp has clocked at least 40 hours of play time.
I tried to vary the genres I listened to so as to get a good impression of how the amp handles them. Classic rock, techno, choral, world, classical modern rock, pop, various soundtracks and a good dollop of J-Pop went into the mix. Listening was done with my HD 595s, Alessandro MS-1s and HiFiMAN RE-ZERO on high-current mode.
The E11 connected to my iPod by the supercolliding superband. The LOD connectors are made of children's teeth and the wire of unicorn hair. My iPod's silicone case is lined with platinum foil to make it invisible to electromagnetic demons.
TREBLE – Present, not really forward or recessed in any way. Perhaps a little muffled at times, a bit congested. Even on the treble-happy RE-ZERO with a treble-heavy track the sound is a little too polite for my tastes. This rather boring treble presence has a habit of taking life out of guitar-heavy rock pieces and some classical tacks lose their airy feeling. In fact whichever word is the opposite of ‘airy’ is a good way to describe this. This is groundy treble indeed.
What you do get for this politeness, however, is a smooth and well-behaved sound. Sibilance is only there when it’s on the track or when the headphone demands it, and detail is as present and correct in these higher bands.
MIDS – Now this is where the action starts. Mids are breathy and sexy. Female vocalists like Lia are presented very well here. Again the sound is very well behaved for the most part, but less so than the treble. Sometimes the mids just kind of build up into a wall of sound when things get busy, yet with simpler vocals and instruments they come in just between lemons and grapefruit on the sub-lime scale. Mid-focused rock sounds nice, but again not as exciting as I’ve known it with my cans.
BASS – Straight off the bat I would describe this as a ‘dark’ sounding amp. The bass easily dominates the spectrum, fairly forward in its presentation and very much in your face. And there are two more levels of bass above this.
Lv0 – ‘The Derringer’. Fairly clean sound. It’s still more prominent than the mids and treble but goes very deep and mostly doesn’t leak into the mids at all. A little loose here and there but well rounded. It even adds a good bit of body to the RE-ZERO, though at the expense of some clarity. Even at this level I find that the bass presentation can get fatiguing after a while with any headphone.
Lv1 – ‘The .44 Magnum’. You thought Lv0 was deep? Well this is deeper. On the MS-1s it really feels like it’s reaching your bones. The thunder at the beginning of Dire Straits’ Brothers in Arms sounds like actual thunder. It’s stunningly visceral, if a little exhausting after more than a couple of minutes. Even still, it keeps well out of the mids and keeps relatively tight.
Lv2 – ‘The Manhattan Project’. You want MORE? This I would class as excessive bass, even on the RE-ZERO. It’s not really so much of a leap as from Lv0 to Lv1, but it is louder, though at the cost of coming into the midrange a bit and losing control somewhat. Again, it’s fun for about two minutes, but then you get a headache. And then your skull shatters.
Imaging – Imaging on the E11 seems a bit limited compared to my other amp. This could be because of the better stereo separation on the E11, but it gives the distinct impression of the sound coming from two places next to my ears rather than being a broad sweep of sound. It also seems a bit less open than my DIY monstrosity.
Do I like the sound, overall? I'm not sure. Certainly it beats no amp at all, but the presentation and forward nature of the sound seem to have me grating my teeth sometimes. I'll admit that it's probably not quite my preferred signature, but I can hear that it's doing what it does well. This shouldn't be discouraging anyone, since we all have different tastes.
Hiss – Yes, there is hiss. On low gain and no bass boost it’s barely perceptible, if at all. On high gain and/or with bass boost there is slight hiss with sensitive ‘phones. It’s not intrusive and doesn’t get in the way of music, but is a consideration if hiss really ruffles your feathers.
High gain/Low gain – I couldn’t tell any difference between high and low gain apart from hiss and loudness. Gain should be chosen depending on the cans used to get the maximum use from the volume control.
The size of a credit card. Also you can stalk/pretend to be me at the RYA or something, well done.
Q&A
Do you need it?
Now the price point and the aura that surrounds the FiiO name (not to mention hundreds of unfounded recommendations) will have many thinking of the E11 as their first amp. I’ll try and put this simply: if your headphones are all cheap, easy to drive IEMs and a pair of ATH-M50s, the E11 might improve your rig by letting you run from an iPod LOD (or you really, REALLY want that extra 6dB of bass), but improvements due to amping will probably be slim. I would recommend saving for a good source over the E11.
If you’ve just bought a pair of HD 650s or a Beyer 600Ω because someone told you they were the dog’s bollocks, the E11 might improve your headphones a bit but it won’t be driving them to their full potential. Save up and buy or build a good desktop amp.
If you own hard-to drive portables like the RE-262 or simply want something small to use for your Grados in the office, congratulations! This amp is probably for you.
Is this, like, the best amp in the world?
No. My DIY amp what I built for around £120 obliterates in every single respect. Then again, my DIY amp weighs 5kg, has to be plugged in to mains to work, and can’t really be strapped to my iPod in a useable scenario. Not bashing the E11 for its price and form factor, just reminding everyone that it’s not the second coming of Fritz Sennheiser.
On top of my AMB γ1. Note that my γ1 does not contain a γ1 yet, because I am lazy and poor and have exams and am writing reviews instead of revising. Nice one, Head-Fi.
Concluding thoughts:
The E11 is a pretty damn good amp. It’s got a killer price, a good build, sounds nice and looks good doing it. I don’t think the sound is quite as good as I had hyped it up in my mind to be over the six months in which I followed its development, nor is it going to revolutionise the bloated and overpriced portable amp market like I think some people hoped. However, even just its price means that it will probably cause a splash among newcomers, providing a way to experience fairly powerful amping without breaking the bank. For ~$60/£40/whatever they’re actually selling them at you can’t really go too far wrong.
There will always be those with unrealistic expectations even at this price tag, and as the old saying goes ‘Haters gonna hate’. Still, FiiO should be proud of the accomplishment the E11 represents and I hope to see more of their products in the future that reach this level of bang for buck.
tl;dr
Good build quality, nothing that will blow your mind. Bass boost will actually blow your mind, though. Good sound across the board, bit boring but with bass emphasis. Good battery life. Recommend it at the price if you need a portable.
Disclaimer: anything in this review could be a lie. I could be insane. I could be a paid FiiO employee. None of this is the absolute or final truth in any way, shape or form.
Also this was my first review on Head-Fi, so if something doesn't make sense or needs elaboration just tell me, 'kay?
Edited by JoetheArachnid - 6/15/11 at 11:25am



































). I will be buying this even though it is not the 2nd coming of Fritz Sennheiser. I'm cheap like that