Oppo HA-2 review

The HA-2 is one of the most attractive and sophisticated-looking headphone amplifiers we’ve seen. The combination of black leather and aluminium and it feels lovely to touch, and small details like the volume adjustment knob and contrasting white stitching add to the appeal.

About the size of a 5in smartphone and twice as thick, the HA-2 includes two black elastic bands for attaching phone and amplifier together for easier transportation. However, the bands will obstruct most smartphone touchscreens.

It can drive headphones up to 300ohms, which isn’t quite as powerful as other headphone amplifiers we’ve tested, but should be sufficient for all but the most specialist headphones. There’s only a 3.5mm headphone jack available and no option for 6.3mm, which you might find on some of the more demanding headphones. A 6.3 to 3.5mm adaptor can be picked up cheaply, however.

The HA-2 acts a DAC as well as a headphone amplifier, with a full-size USB port for connecting to an iOS device and Micro USB for PCs or smartphones that support USB OTG. Using either will remove the digital-to-analogue conversion away from the connected device in favour of the HA-2’s built-in ESS Sabre ES9018-K2M DAC, which in most cases will be superior. Asynchronous USB means the HA-2 controls the flow and timing of the audio datastream by ‘pulling’ from the source device, rather than having it pushed. This can help cut down on audio jitter and other interference.

It supports high-resolution audio and PCM up to an impressive 384kHz at 32-bit. We connected the HA-2 to desktops, iPads and Android smartphones, as well as in ear monitors and full-size cans, and heard improvements across the board.

Trebles shone in particular, with a greater level of clarity in our high-resolution test tracks. Guitars being plucked sounded detailed and delicate and we could hear vocalists’ intakes of breath during live tracks we hadn’t noticed in the past. Bass was warm, but remained tight and controlled. Sound quality will be dependent on your audio source and choice of headphones, but with a good pair, the HA-2 will help bring out the best in them.

Bass+ mode also adds some extra warmth to the low-end. It’s a subtle change to the sound signature and you might find it helps with headphones that have poor bass presence. Turning it on thankfully didn’t muddy the sound.

The HA-2 lasts around 7 hours when devices are connected through USB, or 13 hours when using an analogue source through line in. It supports rapid charging too; you can charge to 70% capacity in about 30 minutes when using the supplied USB wall adaptor.

Usefully, the HA-2 also acts as a portable battery charger. Unfortunately this won’t work over the Micro USB port, so you can’t simultaneously charge and play music on an Android smartphone. A battery indicator button illuminates a bank of four small LEDs to show you the battery level.

The Oppo HA-2 is certainly not cheap, but its performance and great design go some way to justifying the price. Creative’s Sound Blaster E5 is cheaper, but is best used as a stationary DAC; if you have a quality pair of headphones and want to appreciate them on the move, the HA-2 is a fantastic choice.