OPPO's equipment is very interesting although the brand has a relatively brief history. The company hasn't started neither from headphones nor from audio devices. Instead it's an example of a modern company with a purely technological profile, focused on consumer electronics. Its headquarters is located in Mountain View, California, so practically in the heart of Silicon Valley. This is shown not only by its products, but also by the entire background, organized in a flawless manner, typical for really large, wealthy corporations. If you take a moment to look through the company's website, its Facebook page or Instagram profile, you will immediately understand that this is definitely not another garage manufacture, which was more successful than anyone could have imagined. Here, it seems that everything has been well planned and calculated.
OPPO's Blu-ray players as the first products that gained publicity on the audio-video market - according to many specialists, they offer a much better quality than even twice more expensive, high-end sources. A lot of people believe that it doesn't make sense to buy more expensive players, even if someone had funds and - let's call it - caprice. After such an entrance to the video market, it was time to conquer the audio segment. The company hasn't launched high-end amplifiers and speakers, but chose more specific and quite difficult environment - headphones and mobile equipment. This market has recently become very trendy and dynamic, but also tough because of the huge competition. For several years headphones are experiencing a renaissance, first due to the growing popularity of smartphones, and now thanks to demand for domestic headphone systems. Will this mission be as successful as conquering the video market?
Design and functionality
PM-3 is the cheapest model of headphones in the current company's offer, and the only one with closed-back construction. From the outside, the headphones look almost identical to higher PM-2 and PM-1 models, so very elegant. They have only undergone a small weight loss program. The ear pads are a little smaller, and plastic was used in less sensitive areas instead of metal. Key structural elements such as forks holding the ear pads or their covers are still made of metal, which can be felt while holding the headphones in our hands. PM-3 had to lose weight because the designers wanted them to be the first OPPO's mobile headphones suitable for home use as well as outside. In my opinion, they are still more similar to PM-2, than typical mobile headsets, like B&W P5 or Sennheiser Urbanite, but they have been slimmed enough to take them on a trip or even a walk round the city. In relation to the PM-2, which weigh exactly 385 g without cable, here the weight is 320 g. These are not featherweight headphones, but nor a helmet, which no reasonable person put on the head leaving home. The build quality is - without question - very, very high.
A few equipment elements invite to use the headphones outdoors. The first and probably the coolest one is a hard, denim case, in which we can store folded headphones- their ear pads rotate at 180 degrees, allowing the headset to be flat. We also find the soft bag with cable for home use. The standard cable length is 3 meters. One side of the cable is ended with 3.5-mm jack (to be plugged to the left ear pad), and on the other side we find similar jack with the option to use 6.3-mm adapter. But that's not all. Three smaller boxes, containing the 'mobile' cables in three versions, with a length of 1.2 meters, were included to the package which arrived to our office. The first one is for Apple devices, the second one - for Android and Windows Phone devices, and the third - universal, without any remote control. Interestingly, the cable for Apple devices gives us the ability to control virtually all of the necessary functions, from answering calls or changing songs to adjusting the volume and scrolling through tracks, while the remote control for other platforms has only four functions - to answer and end calls, play and pause music. Naturally the owners of iPhones and iPads will be most satisfied with this.
Regarding functionality, PM-3 has only one flaw - their weight is instantly felt on the head and I needed a few minutes to get used to it. But on the other hand these headphones do everything in their power so their presence isn't annoying in any other way. The pads covered my ears entirely, ear cushions were very sensuous, and the overall comfort of listening was raised by the isolation from external sounds, reminiscent of pro closed-back headphones. I haven't noticed any major disadvantages. PM-3 have such a refined design that I began to wonder how a debuting company was able to design and make something like this. I don't know, but the effect is enviable.
Among all OPPO headphones, the PM-3 interested me most and for one reason - these are one of the few headphones using planar magnetic drivers which you can really use outside. Nearly all headsets made by STAX, Audeze or HiFiMAN are enormous helmets compared with these. Nobody would go for a walk in them, not to mention taking them to the bus or for a bike ride. Theoretically these are normal headphones, but they have so much in common with mobile equipment as shopping trolley with a car. The open-back construction makes them suitable for home listening, preferably with a powerful headphone amplifier. PM-3's are one of the few planar headphones that don't cause such trouble. They can be used at home as well as on a walk. So we have probably one of the first headsets of this type that can be used in all conditions. How will this affect the sound performance?
Before the listening session I was expecting something that will draw my attention - sound which will be light, fast, maybe in some ways unique. The exceptional technology usually brings exceptional effects - coaxial drivers, tube amplifiers, electrostatic panels, horns and others always distinguish themselves by something special, which some people love and others hate. While I was putting PM-3 on my head, I was expected something like this - the 'love it or leave it' sound. And? I got extremely mature, balanced, and one hundred percent neutral sound, which I would rather call 'something for everyone'. The smallest OPPO headphones were tuned to be capable of playing every kind of music. There is no element in this sound you could criticize. It's simply not possible because everything is perfectly fine. Frequency response is flat as a frozen lake, sound temperature is transparent like water from a mountain stream, all parameters are set for a perfect neutrality. For some it means boredom, for others - perfection.
Even if we begin to look into the performance, considering soundstage, bass and clarity, sooner or later we discover that OPPO engineers managed to find the best possible compromise. PM-3's sound is neither too aggressive nor woolly or slow. Low frequencies don't mutter on each occasion, nor are artificially compressed or boxy. Treble is perhaps the most characteristic element, if I may say so, because it's also aimed at high fidelity and neutrality. Soundstage? it's nor particularly extended to the sides, or squeezed inside the skull. Really, if someone started asking me about further aspects of the sound, for every question I would have to answer that it is just fine, correct and really audiophile.
Such situation has its pros and cons, and the superiority of one over another doesn't depend on the headphones, but rather on our attitude to them and the way of our understanding of good sound. If you think that good equipment is one that's able to catch something interesting for each recording and surprise the listener, or just has something special and plays like nothing else in the world - you definitely shouldn't walk this way. PM-3's are the type of headphones which by definition don't do such things. It's rather something for people who don't want to be surprised, and prefer to be sure that headphones will always play at the high level, in a manner consistent with the intent of the musicians. They gain trust of the listener in the first few minutes, and apparently they care about not losing it. Their sound is one hundred percent compatible with the idea of high fidelity, and in this concept, there is little room for craziness. I used PM-3 for a few days and during this time my attitude hasn't changed. It's just very good, versatile equipment for any music and every occasion.
At the end I tested the PM-3's capabilities in combination with the iPhone 5S. I expected that the sound would 'fall apart', but I was wrong. iPhone with Spotify app played almost as good as a desktop system, which proves that the PM-3 actually are portable headphones. What's more - I'm sure that none of the headphones I reviewed sounded so good with a smartphone. Usually I either got some headsets designed for the portable equipment, usually priced at €200-300, so it was hard to expect amazing performance. On the other hand, large, high-end audiophile headphones usually react allergic to any smartphone or tablet. PM-3 is a combination of two worlds. They play just as well as hi-end headphones designed for home use, and at the same time they are able to cooperate with smartphones and tablets. If I was waiting for some small surprise during the review, the configuration with the iPhone was a huge and very pleasant one.
Build quality and technical parameters
PM-3 is currently the cheapest handset in OPPO's catalogue using planar transducers which are very similar to those used in the flagship PM-1 model. Each driver takes form of a round, flat membrane with a diameter of 55 mm, made of seven thin layers for maximum durability while maintaining low weight. The structure of the membrane is designed to provide excellent stability, even at high thermal loads. The membrane has built-in flat, spiral conductors on both sides and the double-sided structure leads to even higher efficiency. PM-3 use drivers based on very powerful neodymium magnets optimized with FEM method. Thanks to these technical solutions, headphones have a sensitivity of 102 dB, which is a very good result and translates into easy power handling, even with mobile devices. The manufacturer even claims that no other planar headset comes even close to such a result, although the situation is changing rapidly - just to mention Audeze EL-8 with identical efficiency. Combine this with impedance measured at 26 ohms and you get a pretty user-friendly product. As for the other parameters worth mentioning, we can certainly pay some attention to the clamping pressure of 5 N. Seems like a lot, but it's justified by the closed headphone design - if you want to isolate yourself from the environment, earmuffs can't be loose on the ears, but adhere well to our head.
Asus Zenbook UX31A, OPPO HA-2, T+A E-Serie Power Plant Balanced, iPhone 5S, iPad Air 2.
PM-3 is a decent piece of hardware. I still can't understand how the company managed to design such headphones without thirty years of experience on the market. OPPO offers unique drivers in a truly luxurious package, tuned with great understanding of music and all this has been achieved without being a nightmare for the amplifier. PM-3's are easy to drive, and their natural sound is very likeable, easy to get used to. Although I haven't tested the more expensive PM-1's or even PM-2's, it seems to me that the PM-3 may be the best bargain of all current OPPO headphones.
Acoustic design: planar, closed-back
Frequency response: 10 Hz - 50 kHz
Sensitivity: 102 dB
Impedance: 26 ohms
Driver: 50 x 50 mm
Cable length: 3 m
Optional cables: 1,2 m