While listening to music on the go through a smartphone or MP3 player is convenient, the audio quality can be lacking at times, as such devices lack the power to drive music to the fullest.

That's where the Oppo HA-2SE portable headphone amplifier comes in. It sits between the music player and headphones, and boosts the digital-to-analog output of music files so that they sound better.

The HA-2SE is the successor to 2015's HA-2, with updated circuitry to a top-of-the-line digital-to-analog convertor chip.

It's fuss-free to set up and is very cleanly designed. A knob on the top controls the volume, while a gain button on the right lets you drive power and volume even further. Next to it is a bass toggle for adding more body to the low-end.

Listening to music with and without the amplifier showed a telling difference. The amplifier kicks up the audio experience a notch, giving the songs in smartphones more power, body and clarity.

Songs may not necessarily be louder, but they are clearer and smoother, with more details coming through.

I found the performance improvement most noticeable on headphones rather than earphones, as the latter tend to be designed with low impedance in mind.

The svelte, slim profile of the HA-2SE, which comes with a handsome leather lining, makes it easy to carry around.

The HA-2SE comes with a lightning cable to connect to Apple devices, and a micro-USB for others.

It doesn't, however, come with USB-C support, and USB-C cables I've tested don't work. So users with USB-C phones are stuck with using the analog 3.5mm cable to boost their songs, which isn't as powerful as a USB cable.

The HA-2SE also works as a portable battery charger. Its 3000mAh battery gives about 7hr of continuous use, and can be used to charge your phone in a pinch as well.

It charges in 1½hr, with a quick- charge feature that gives it 75 per cent of juice in 30 minutes.

But the HA-2SE might be a tough pill for most consumers to swallow. At $479, it is the price of a good pair of headphones.

Paying almost $500 for better sound quality is not something I see most consumers doing.

Only diehard audiophiles who already have equally pricey music players and headphones may want to spring the cash to enhance their audio experience on the go.

• Verdict: The HA-2SE makes music on-the-go just a more expansive and better experience. It is, however, too expensive for mass appeal. The lack of USB-C support also reduces its usefulness among new smartphones.