I recently review the Oppo HA-2 Headphone AMP/DAC which simply outclassed many rivals whilst looking fabulous. So I decided to give the Oppo PM-2 Headphones a go. The PM-2’s are unique as they use Oppo’s Planar Magnetic Technology. I have never bought headphones using planar magnetic technology due to the power requirements. However, Oppo have you covered here as the PM-2’s have high sensitivity.
Many planar magnetic headphones have a sensitivity far below 100 dB and require very powerful amplifiers to drive. The OPPO PM-2 has a sensitivity of 102 dB, which allows it to pair well with both mobile devices and scale upwards when used with high end headphone amplifiers.
The OPPO PM-2 utilises a planar magnetic driver that sets it apart from the majority of headphones on the market. Sound is generated by a very thin and light diaphragm whose entire surface area is evenly driven. The diaphragm is driven in a symmetric pull-push manner, and the magnetic system and conductor patterns have been optimised for maximum sensitivity and consistency. This allows the diaphragm to generate very stable and linear piston-like vibrations, ensuring phase coherence and high resolution performance with minimal distortion.
When looking at phase coherence that is when sound enters our ear, the PM-2’s have a planar wave front with all spectrum components in phase. A typical dynamic headphone driver disrupts this coherence with its phase irregularity, resulting in less than perfect signal peak reconstructions. OPPO’s planar magnetic driver has much better phase coherency since all parts of the diaphragm are vibrating in concert without break up and delayed resonance.
In addition, OPPO’s planar magnetic driver has a flat conductor pattern that does not have any inductive components. This eliminates inductance related intermodulation distortion, which is especially common in dynamic drivers with high impedance and a high number of voice coil turns.
Another reason why I haven’t used planar magnetic headphones before is that they normally have large balance deviations between the left and right channels, and obviously accurate stereo reproduction is contingent on having a very close match between the left and right channels. During the OPPO PM-2’s manufacturing process, drivers are closely matched to ensure optimum stereo imaging and soundstage.
Also, OPPO’s planar magnetic driver diaphragm has 7 layers of thin materials that provide excellent performance, reliability, and longevity. The construction of the diaphragm ensures that it is very stable under thermal stress and vibration. The diaphragm utilises a spiralling pattern of flat aluminium conductors on either side of the driver. The double-sided design allows twice as many conductors to be placed within the magnetic field, which leads to higher sensitivity, better damping, and even drive force.
The full specifications are –
– Acoustic Principle – Open back Ear Coupling Circumaural
– Nominal Impedance 32 Ohm
– Sensitivity 102 dB in 1 mW
– Clamping Pressure 5 N
– Cables 3 m detachable OFC cable (6.35 mm) and 1 m detachable OFC cable (3.5 mm)
– Cable Connectors Output: 2.5 mm mono mini jacks
– Input: 6.35 mm stereo jack, 3.5 mm stereo jack
– Weight 385 g (without cable)
– Included Accessories Carrying Case and 6.35 mm and 3.5 mm cables, User Manual
– Driver Specifications Driver Type Planar Magnetic, Driver Size (Oval) 85 x 69 mm, Magnet System Symmetric push-pull neodymium
– Frequency Response In Free-Field 10 – 50,000 Hz
– Long-Term Max Input Power 500 mW according to IEC 60268-7
– Pulse Max Input Power 2 W
The first thing that strikes you in the packaging. The PM-2’s are beautifully packaged. You also get a protective carry case. 2 sets of cables are included one for home listening and the other for home audio equipment.
The PM-2’s are built solidly and the pads are extremely comfortable. I have found I can wear these for hours and hours and still have no discomfort.
Burning in period. I was advised that planar magnetic headphones need 200 plus hours of burning in. So the easiest way is just to leave this plugged in for 2 weeks playing music non stop. For the first time, I really witnessed a massive before and after in the sound quality. So after 250 hours this is my view of the listening experience with a range of music.
Genres used – Jazz, Blues, Pop, Rock, Female Vocal. FLAC recordings via Tidal and 320mp3 bitrate songs otherwise. Below are a selection of the songs I have listened to for this review. I auditioned the headphones using two methods. Firstly, using my Samsung Galaxy Note 4 as the source and its own headphone jack/amp with an app called Poweramp. The other method was using an app called USB Audio Player Pro, USB out into the Oppo HA-2 Headphone/DAC, the HA-2 being used for its DAC only and then line out into the Cayin C5 power amp to deliver as much oomph as possible for the PM-2’s. Naturally using a separate DAC/Headphone amp improves the audio performance, but the quality via the Samsung Note 4’s own headphone jack was rather impressive too.
Sally Barker – To Love Somebody/Dear Darlin – The PM-2 deliver the vocals, guitar and all the detail on the song with such exquisite precision. Sally Barker’s voice sounded so so emotional, no words can really describe the sensation.
Adele – Rumour Has It/ Lovesong – beautiful vocals, fast rhythmic drums, instruments and the a great beat – all so well captured and played. Lovesong has a guitar piece at the beginning of the song. The PM-2’s presentation is off the charts, I could just put this song on repeat and listening to it for hours. And then the bass track arrives, again reproduced perfectly by the PM-2’s
Paloma Faith – Can’t Rely on You – punchy, musical and a superb presentation. Paloma Faith’s voice stands out with her lovely vocal tones.
Yolanda B Cool & D Cup – We No Speak Americano – I choose this song for those that like a bit of dance music. The pace provided recreated by the PM-2’s is really toe tapping stuff, deep bass, and they pick up all the nuances within the track. I really enjoyed what the PM-2’s did with this song.
The Louis Lester Band – Downtown Uptempo/ Sweet Mary Jane – from Dancing on the Edge. My recommendation is listen to the whole album. Close your eyes and let the music melt away before you. All the instruments, vocals and just about everything on this is so impeccable and musical. Jazz/Blues genres explode to life on the PM-2’s. I don’t know if you have ever heard an artist perform, and the hairs lift on your arms. Well, this is exactly what the PM-2’s did with this album. So so good.
Queen – Bohemian Rhapsody – good separation, stunning vocals, and its Queen. So thumbs up again! What makes this track sound so special is the lifelike vocals by the PM-2’s.
Bastille – Weapon/ the Driver – the electronic sounds and fast beat really well delivered. Great vocals feeling life like vocals again. The timbre of the vocal tones is stunning. Also, the PM-2’s scale rapidly as the music explodes.
Nicola Benedetti – The Lark Ascending – natural lifelike sound again. The violin is so real in your ears. I didn’t want the song to end. Beautiful. It was as if Nicola Benedetti was playing next to me. The level of detail extracted was huge with the ability to hear all sorts of extra nuances.
So in summary the Oppo PM-2 Headphones are breathtaking. The musical experience is off the charts like nothing I have ever heard before. A HUGE recommendation from me!!
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