I would like to preface this review by saying that as an IEM user, portable amps have never really won me over to the same extent as many other members of the community. While they certainly have their uses, I’ve never felt the compulsion to single out my amp for an upgrade in order to take my listening experience to the next level. There certainly are earphones that benefit from amplification and some that downright require it, but they are few and far between. Whether I like it or not, however, portable amps are an inseparable part of the Head-Fi scene. My personal collection of portable amps is rather small – a trusty DIY mini3, an iBasso D10, and a T4 microamp. I’ve owned about a half-dozen other portable amps, some low-end, some not so much, but I’m far from being an amp guru. That said, this is my take on the new Music Valley Rocoon RC-1.
As with all reviews, this is my subjective opinion and should be taken as such, perhaps even more so than usual since an evaluation of an amp depends on so many other factors. For reference the amp was used with my Sandisk Sansa Fuze using a vampire wire LOD as well as with the line out of my iBasso D10.
Music Valley is a Chinese company known in limited circles for their SP1 (Silver Prologue 1) in-ear earphones. I liked the sound of the SP1 but they never really caught on the way some of the other Chinese earphones have. The Rocoon line of portable headphone amplifiers is Music Valley’s latest hi-fi venture. Though details are hard to come by for a non-Chinese speaker, the range seems to consist of two amps at the moment – the pricier RC-1 and the cheaper RC-2.
I got the amp about a month and a half ago as a gift from a friend in China. At the time I could find no trace of it anywhere online. In recent weeks, however, I’ve started seeing both the RC-1 and RC-2 popping up on Taobao. From what I can see, the RC-1 retails for about 920 Yuan, or close to $135, which is on the lower end of mid-range portable amps. I thought that since I already had it in my possession, the RC-1 deserved a closer look on the chance that it will make its way to eBay and become available worldwide in due time.
Packaging & Accessories
The RC-1 comes in a fairly plain thick cardboard box with the Rocoon logo. The only hint of affiliation with Music Valley is a hologram sticker on the side of the box. The box contains the amp, four thumbscrews for the rear panel (two of which come installed), a soft gray carrying pouch, and an instruction manual (in Chinese).
Design & Build Quality
Like so many mid-range amps, the RC-1 is contained in a rectangular enclosure with a black gloss finish. In terms of size, the amp is just a bit smaller than the mini3 in width and length, stacking perfectly with the Sansa Fuze whereas the mini sticks out slightly. Compared to the all-aluminum Hammond enclosure on my mini3, the RC-1 box feels noticeably less solid. The metal panels are much thinner than the extruded aluminum of the Hammond box. This is mirrored by the weight, which comes in at just over 100 grams with two AAA batteries in place. My mini3, on the other hand, despite being very similar in size, clocks in at 160 grams with battery. For comparison purposes, my iBasso T4 weighs a mere 29 grams and the Sansa Fuze – twice that.
Size comparison (Bottom->Top): iBasso D10, mini3, Rocoon RC-1, iBasso T4
The front of the amp holds a smooth volume knob, input and output jacks, and a dedicated power switch. The 3.5mm jacks are just far enough apart to accommodate two Neutrik plugs side by side. The gold lettering on the bezels offsets the piano-black paintjob and an embossed Rocoon logo can be seen on the rear panel of the amp. Assembly quality is good and two rear thumbscrews, placed diagonally, are sufficient to hold the amp together. I wouldn’t call it rock solid but I definitely don’t expect anything to go wrong with it. A pair of 1.5V or 1.2V AAA batteries is required to power the amp, with 200 hours of battery life specified. My none-too-fresh rechargeable AAAs easily managed well over 100 hours, so 200 hours for a fresh set of batteries is not at all otherworldly.
The RC-1 is a very simple amp to operate. There’s no charging circuitry, no bass boost, and no gain adjustment. Flicking on the power switch with batteries installed turns on an orange LED on the front panel to indicate that the amp is operational. There is no audible click when powering on the amp and the noise floor is extremely low. The volume control is the only means of interaction with the amp. Care should be taken to make sure that the volume is at a minimum on first start, which was not the case with my unit and resulted in an unexpected taste of the amp’s power.
The most striking thing about the RC-1 is the sheer amount of power that the amp puts out. I usually do my listening at rather low volumes and even at minimum volume most of my IEMs are far too loud to be usable with the RC-1. The fact that a small amount of channel imbalance, a common issue with budget amps, is present at the lowest volume levels doesn’t help either. I don’t have any issues with the volume of my 5x gain mini3, which should say something about the power of the Rocoon. The only IEMs that I managed to use comfortably with the RC-1 were the 150 Ώ Yuin OK1s. Of course adding an impedance adapter can make any other earphone usable but in the interest of reproducibility, most of my listening was done with a pair of Sennheiser portables – the HD25-1 and HD238. Despite the familial ties, these two headphones couldn’t be more different in sound signature. The only unifying factor is that both of the headphones scale well with amplification.
My general impressions of the amp are that it is off-neutral compared to my iBasso D10 and mini3, leaning slightly towards warmth and greater bass impact. As a result, it has a tendency to even out treble-happy headphones and earphones, making it a very good match for the HD25-1 and a poor match for the HD238, which is severely veiled at the top to begin with. Power is plentiful – with the HD25-1 my absolute maximum tolerable volume is 15-20% of max with the RC-1. To test the power overhead, I tried the RC-1 with a Beyerdynamic DT770/250 as well as the AKG K601. Scaling is not the issue with either of these – they simply need an amp. With the DT770/250, the RC-1 fared surprisingly well, toning down the treble and giving the sound ample muscle and a broad dynamic range. It had a greater volume reserve than either my mini3 or iBasso D10 and only gave up a small amount of resolution and transparency to the D10. I was surprised to find the DT770/250 more enjoyable with the RC-1 than my Heed CanAmp and Tianyun Zero desktop amps.
With the K601 results were expectedly less impressive. To my ears the K601 lacks sparkle to begin with and by its nature the RC-1 does not pair well with headphones that are laid back at the top. And of course the K601 easily took all of the power that the little Rocoon amp had to give and asked for more. The authority and control that the K601 show when paired with my Heed CanAmp just wasn’t there, as anyone who’s ever owned them may expect.
Overall, I am conflicted about the RC-1. Having a portable amp with such driving capacity and well over 100 hours of battery life from a pair of AAA rechargeables is certainly very appealing. However, buying such an amp for all but the hardest-to-drive IEMs doesn’t make much sense.
The Rocoon RC-1 is by far the most loud-mouthed sub-$200 amp I’ve heard. It is off-neutral and not as transparent as a few of the others. On the upside, it is lighter, slightly smaller, and has vastly superior battery life in comparison to my mini3. If I absolutely had to use a portable amp with something like the DT770/250, the RC-1 would be my first choice. For IEM users who prefer reasonable listening volumes, the RC-1 is overkill. This seems to be the story with the RC-1 – it’s designed for low-efficiency, power-hungry phones and performs accordingly. With certain headphones it outperforms the mini3. With others it does not. Whereas the mini3 is what I would consider a ‘safe choice’, the RC-1 tends to be finicky. Depending on the headphones used, the RC-1 can either alleviate their weaknesses or exacerbate them. With a 2-year warranty on the Chinese market and excellent all-around usability, I would say the RC-1 is worth it for those able to put the power to good use portably. If you’re still using Sennheiser CX300s, best to give this amp a pass.
Edited by ljokerl - 9/14/10 at 9:48pm