Oppo HA-1 Headphone Amp and PM-2 Planar Magnetic Headphone Review


Headphone TypePlanar Magnetic
Sensitivity102 dB @ 1mW
Nominal Impedance32 Ohm
Review DateDecember 1, 2014
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When Oppo is mentioned, most Hi-Fi aficionados think of reference quality Blu-ray players. Now they can add headphones and headphone amps to that list. Oppo is taking a serious interest in the lucrative headphone market, and I don’t mean a run-of-the-mill Beats clone. Oppo has high-end personal audio in mind with the new HA-1 Headphone Amp + DAC and the PM-2 Planar Magnetic Headphone. The HA-1 has been available for several months, but the PM-2 is a new release. The PM-2 is a more affordable version of the earlier released Oppo PM-1.

They share the same internals that produce the sound and only vary in material finish and included accessories. At $699, The PM-2 is not a low end headphone, but is a low priced planar magnetic headphone. Oppo has the planar magnetic $995 Audeze LCD-2 and $900 HIFIMan HE-560 beat in price with only the $500 HIFIMan HE-400i costing less than the PM-2. The Oppo HA-1 is a hefty amp, capable of powering any of the popular power hungry planar magnetic designs including the $1,300 HIFIMan HE-6. This headphone amp and its ESS ES9018 DAC will happily sit in a reference personal audio system as the anchor.

Quality Fit and Finish – Inside and Out

Headphone Type:Planar Magnetic
Sensitivity:102 dB @ 1mW
Nominal Impedance:32 Ohm
Review Date:December 1, 2014
Price:Check on Amazon
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At 10.0″ x 3.1″ x 13.1″, the Oppo HA-1 is not the smallest headphone amp on the market but it is extremely well built. Constructed with brushed aluminum and weighing 13 lbs, the build quality of the Oppo HA-1 is off the charts. The body is available in either a silver or black finish. The top plate of the HA-1 has a vent for the heat generated from its Class-A amplifier design. The reason for all that heat? The ability to drive all the popular power hungry headphone designs like the HIFIMan HE-6 and Audeze LCD-3. With a 600 Ohm load, the HA-1 can push out 2400 mW via the XLR balanced output and 3000 mW into 32 Ohm. The Oppo HA-1 is a fully balanced design, from DAC to output, and even single ended input is converted to balanced at the input buffer. The balanced headphone output provides twice the voltage and four times the power of the single-ended output. This means using a balanced cable with the Oppo PM-2 provides more headroom and better dynamics. I found the balanced output to offer the best performance for the Audeze LCD-3 and HIFIMan HE-6.

HA-1 Inputs and Outputs

HA-1 Inputs and Outputs

The Oppo HA-1 uses an analog potentiometer for volume control and a motor provides remote control of the volume setting. This volume control design is expensive and harder to manufacturer, but is the most audibly transparent volume control method available. To best match the range of headphone sensitivities, the Oppo HA-1 includes a gain setting of Normal and High. Supplying clean and robust power is a toroidal linear power supply.

The heart of the Oppo HA-1 DAC is an ESS Sabre32 Reference ES9018, currently the best consumer digital to analog converter. With an astounding dynamic range up to 135dB and a THD+N of -120dB, you really can’t ask for anything better than that. Asynchronous USB utilizes the XMOS USB chip for processing PCM up to 384 kHz 24-bit and DSD up to 12 MHz (DSD256). The Oppo HA-1 even has Apple MFi certification to allow it to read digital audio directly from iProducts. Also included is an external Bluetooth antenna for audio streaming utilizing the higher quality, but still compressed, aptX codec.

The Oppo HA-1 has a home theater bypass mode allowing it to function as a two channel stereo pre-amplifier in a home theater setup. To further its ability as a pre-amplifier, Oppo has 12V triggers for input and output. These triggers allow the Oppo to turn on power amplifiers or be turned on by another device like a surround processor.

Control of the Oppo HA-1 is accomplished either by the front panel knobs, included remote control, or an iPhone or Android phone via Bluetooth. The front panel uses a 4.3” color display that shows input source options, audio spectrum, voltage meter, and current level when adjusting volume.

The Oppo PM-2 Planar Magnetic headphones are a new, more affordable version of the company’s first planar magnetic design, the PM-1. The two versions share a lot in common, including the same driver, made from a 7-layer diaphragm, double-sided spiraling coils, and an FEM-optimized magnet system. If you check out the product comparison page, it becomes apparent that the real differences between the PM-1 and PM-2 are purely cosmetic.

Carrying Case

Carrying Case

The Oppo PM-2 comes with a sturdy, compact case with nice fit and finish. The design of the PM-2 is modern, sleek, and refined. Mostly black with silver accent rings around the ear pieces, these won’t draw too much attention. They are quite a bit smaller than the Audeze headphones and slightly smaller than the latest models from HIFIMan. In regards to the weight, at 385 grams the PM-2 is just a tad heavier than the 377 gram HIFIMan HE-560. That light weight along with ample padding both on the ear cups and the headband make the PM-2 a very comfortable headphone. I have no issues listening to them for extended periods of time and rank them second behind the HE-560’s for overall comfort in the over-the-ear headphone category.

The planar magnetic drivers inside the PM-2 make use of a very thin diaphragm with an embedded conductor pattern that is then driven in a push-pull motion by magnets. In the PM-2, the diaphragm is double-sided which allows for twice as many conductors and greater efficiency. That increased efficiency translates to a less demanding load and the ability of the PM-2 to be driven by portable devices.

Listening to the Oppo PM-2 on both an iPad and iPhone proves to be more satisfying than I expect. Listening to a live recording on YouTube of Sara Bareilles performing Sia’s “Chandelier” sounds full, energetic, and provide ample depth to the soundstage. Volume levels are excellent, especially for a planar magnetic design. If you are wondering if you can start with the Oppo PM-2 and later add a dedicated headphone amp, the answer is yes.

PM-2 Headphone

PM-2 Headphone

The Oppo HA-1 and PM-2 make an undeniably great pair. To truly appreciate that pairing, the optional balanced cable for the PM-2 is required. Not only does this take advantage of the balanced circuit for lower noise, there is also four times the power over the single-ended ¼” output. The gritty tone of Ray Lamontagne’s voice is captured beautifully by the Oppo PM-2 headphones. On “Lesson Learned” the acoustic guitar is in a three dimensional space while Ray’s voice takes up a large presence in the center soundstage. The bells on Bjork’s “Frosti” are intoxicating and take you away into another world. The Oppo HA-1 is about as versatile a headphone amp you will find on the market and hooked up to a computer over USB allows it to shine with high resolution music files.

On the 24/96 recording of Buena Vista Social Club, guitars strum from far stage left and congo’s pop in the background yielding a fully realized atmospheric soundstage. The open-back nature of the Oppo PM-2’s design allows for this wide, expansive soundstage. Further showcasing the depth capabilities of this setup, Sara K.’s Chesky recording of “If I Could Sing Your Blues”, casts the muted trumpet deep stage left and the effect is stunning. Sara’s voice is beautifully recreated via the Oppo gear with zero sibilance and chestiness, only natural tone and body.

To further evaluate the Oppo PM-2’s on their own, I also hooked them up via balanced cable to our current reference headphone amplifier, the AURALiC Taurus MKII. The HA-1 is a fabulous headphone amp, but the Taurus is able to open up the PM-2’s even more. I find the tone to be even more lush and rich. Listening to the 24/192 version of the classic John William’s score for Jurassic Park, I can’t help but turn the volume up. The dynamic peaks when the trumpet line crescendos on “Journey to the Island” sound life-like and exactly what I look for in a high performance setup. If you are looking for energetic punch and rich distortion, the PM-2’s deliverer plenty of that on The Black Keys‘ “Little Submarines.” The Oppo PM-2’s are an extremely capable headphone and their price is not be a sign of lesser quality. These bad boys can hang with headphones in the $1,000-$2,000 price range. Their transparent nature allows the sound quality of DAC’s and amps to come through, which only means more fun experimentation.



The Oppo HA-1 on its own is a solid, versatile unit. I tested it with several models from HIFIMan and Audeze and it has zero issues handling them all. With HIFIMan’s new HE-560 and HE-6, I do find the single-ended output to not generate quite enough juice, but the balanced out handles them well. The circuitry is dead quiet and able to handle the higher dynamic range of 24-bit audio. At the price point of $1,199, the combination of ESS ES9018 DAC, USB input, and high power amp is hard to beat. In fact, as of late 2014, it has very little competition with the same specs.

Oppo a Legitimate Player in the High Performance Headphone Market

I can say nothing but great things about Oppo’s decision to enter the high-end personal audio space. Their debut with the HA-1 and PM-2 is simply marvelous. For $699 the Oppo PM-2 is one of the best buys in the high-end headphone market. There are areas where other headphones perform better, like the low end of the Audeze, or the transparency of HIFIMan, but all-around the Oppo PM-2’s perform beautifully. Their ability to play well via portable devices allows you to start with the PM-2’s and later add the HA-1 to really hear how well these headphones perform. The Oppo HA-1 does it all with style and class. It has plenty of connectivity, loads of power, a reference quality DAC and neat, sugar-on-top features like home theater bypass. Sit down, relax, and enjoy reference quality playback with the Oppo HA-1 Headphone Amplifier and PM-2 Planar Magnetic Headphones. Yet again, a job well done by the folks at Oppo.

Review Summary
Product:Oppo HA-1 Headphone Amplifier and DAC
Reviewer:Stephen Hornbrook
Pros:Versatile unit, Reference ESS ES9018 DAC, USB asynchronous input for high resolution files, Loads of power for even the HIFIMan HE-6, Stylish and well built
Cons:Takes up a bit of space for a desktop setup
Summary:The Oppo HA-1 is a fantastic unit that may seem spendy at $1199, but it offers a ton of functionality and performance at that price. Able to handle just about any of today’s high performance headphones, the Oppo HA-1 would make a terrific centerpiece to a reference quality personal audio setup.


Review Summary
Product:Oppo PM-2 Planar Magnetic Headphone
Reviewer:Stephen Hornbrook
Pros:Same great technology as more expensive PM-1, Lush midrange, Ample low end for most
Cons:Balanced Cable costs extra
Summary:An extremely capable headphone, the PM-2 offers excellent performance in a stylish and comfortable package. Neutral tone with a lean to the warmer side of things, good quality low end performance, and deep three dimensional soundstage make this a top performer.



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Review Summary

ProductOppo PM-2 Planar Magnetic Headphone
ReviewerStephen Hornbrook
ProsSame great technology as more expensive PM-1, Lush midrange, Ample low end for most
ConsBalanced Cable costs extra
SummaryAn extremely capable headphone, the PM-2 offers excellent performance in a stylish and comfortable package. Neutral tone with a lean to the warmer side of things, good quality low end performance, and deep three dimensional soundstage make this a top performer.
Value5 / 5
Performance4 / 5
Overall4.5 / 5

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