Welcome to my review of the Oppo HA-1. The Oppo HA-1 is terrific headphone amplifier, with its own DAC. It can also be used as a pre-amplifier. For the purpose of this review, I used my Oppo PM-2 Planar Magnetic headphones, the special Oppo balanced headphone cable along with the HA-1. The Oppo HA-1 retails for £1,199, the PM-2 headphones £699 and the Oppo Balanced Cable £149.

From the moment you lift the Oppo HA-1 out of its box, you begin to appreciate the quality workmanship of this piece of hardware. Below is a photo of the internal construction. What is striking is just how neat and precise everything is assembled. The front of the HA-1 has connectors for a standard 6.3mm headphone socket, XLR balanced connector, the infra red receiver, power, source and volume controls. It also has a USB input for iOS devices. The HA-1 is approved by Apple in the MFI program. This means that via the lightning cable, it can extract the digital data from your iPhone or iPad and use the Oppo DAC instead.

The rear panel has you covered for many different types of connections.

Internal Layout

Oppo have designed the HA-1 so that the analog audio section is a fully balanced design with a focus on keeping the audio signal in the analog domain once it leaves the DAC. The HA-1 uses a huge toroidal power transformer, linear power regulators, filters with custom made capacitors that ensure that the headphone amplifier has a clean power source with plenty of reserve energy. The fully balanced Class A power amplification section has hand-picked and paired discrete components to ensure symmetry, with a motor-driven precision volume control knob that allows for both manual and remote control volume adjustment while keeping the audio in a pure analog audio path.

Official Specifications

The specifications are lengthy, so I have extracted these direct from the manual –

  
  

Design and Engineering

The HA-1 uses an analog potentiometer (volume knob) to control the volume. This avoids re-digitising the audio signal for volume adjustment. In turn this allows for a clean signal path for the audio. At the same time, Oppo have built this for the 21st Century. A remote-controlled motor turns the volume knob and a 10-bit analog-to-digital converter samples the signal to display a numeric dB level.

The HA-1 passes Apple’s “MFi” certification and is compatibile with the latest iPod, iPhone and iPad to be used as the digital audio output accessory of these devices. By tapping directly into the digital audio signal of these devices and converting the audio to analog using the high performance SABRE32 Reference DAC, the music sounds spell binding. So so good.

The HA-1 supports Bluetooth Advanced Audio Distribution Profile (A2DP) with both the standard and aptX® high quality codec. I paired my phone with the HA-1 and listened wirelessly. Again incredible sound quality.

The Oppo HA-1 can bypass the low fidelity, poor quality DACs of your computer sound card. The HA-1 turns any computer into a high performance multi-media source by converting digital audio to analog through the ESS Sabre32 Reference DAC. The asynchronous transfer mode uses the high precision clock inside the HA-1 to drive the audio signal, not relying on the clock quality of the computer. HA-1’s USB DAC input supports PCM up to 384 kHz 24-bit and DSD up to 12 MHz (DSD256).

The headphone power amplifier has an adjustable gain setting. For optimal sound quality and to best match your headphones’ sensitivity, you can choose between Normal and High for the Headphone Gain setting.

The HA-1 is housed in a brushed aluminum chassis. The Class A amplifier is designed with ample ventilation and built with the finest components to ensure long term stability and performance. The photo of the internal components highlights this point.

The HA-1 doubles as a high fidelity stereo pre-amplifier with both RCA and XLR output ports. A special “Home Theater Bypass” mode can be assigned to any input source, making it very easy to integrate the HA-1 as a stereo pre-amplifier into a home theater sound system.

The HA-1 features 12V trigger input and output. When used as a stereo pre-amplifier, the trigger output can turn on your power amplifiers automatically when the HA-1 is turned on. You can also turn on the HA-1 automatically by connecting its trigger input to the trigger output of a source device or a surround sound processor.

The HA-1 comes with a remote control that provides volume control, direct source selection and even playback control for digital audio sources. A remote control app is available for both Apple’s iPhone and Android-based smartphones. The app works over Bluetooth and offers the same functionality as the physical remote control. The supplied remote control is made of aluminium too.

The Important Part – Sound Quality and Experience

Wow. Simply stunning. Phenomenal.

I hope you get the message by now. In my entire audio experience, I have never heard such an amazing setup. The Oppo HA-1 performs “magic with music.” It oozes musicality, separation, impact, slam, control, finesse and more. You feel the music. I tried as many different genres as possible and nothing phased it. The Oppo PM-2 headphones with the balanced cable are a real gem and work incredible well in partnership.

In previous audio setups, the compromise with high end audio equipment can be the lack of options. This is not the case with the HA-1. The HA-1 has many different connection options. It can be used as a pre-amplifier, connected to via Bluetooth and even comes with a remote control. Or you can use its android or iOS app.

I connected my iPad, my wife’s iPhone 5S and my android phone (LG G4) via USB and bluetooth. In all cases, the mind blowing sound and theatrical music performance was off the charts “brilliant”.

The HA-1 will extract information from tracks that you never knew existed. I also discovered a whole new level of performance from my Oppo PM-2 headphones.

Final Words

This is a phenomenal piece of kit from Oppo and priced extremely competitively too. Highly recommended.

More info and deals on the Oppo HA-1 Headphone DAC Amplifier at Amazon UK