Philips Fidelio S2 review

The Fidelio sub-brand carries a lot of weight for Philips, so much so that the company insists its engineers undergo a training course designed to test their hearing abilities before they’re allowed to work on any Fidelio product. This commitment has paid off in the past, resulting in some fantastic products such as the Fidelio M1 Bluetooth over-ear headphones, but now the company has turned its attention to in-ears.

The Fidelio S2 reviewed here is a higher-end version of the Fidelio S1, but the differences are mainly cosmetic. The S2 is made entirely from copper alloy rather than a combination of metal and plastic. Both have 13.5mm neodymium drivers.

The earphones are fairly large, containing the driver in the outer ear and a smaller tip that slots into the ear canal. A vented back and three small holes drilled into the outer ear create a semi-closed back design for improved bass response. We were worried this would result in sound leaking out and annoying our coworkers or fellow commuters, but this proved not to be the case.

A tough carry case and seven sets of ear tips are included in the box, including two sets of Comply foam tips which create a fantastic seal in your ears to keep external noise out. Even the silicone tips create a firm seal, meaning the earphones never fell out when we were moving. At 14g the headphones don't weigh very much at all.

The flattened rubber cable does a great job of keeping cable noise to a minimum, even when jogging or at the gym. There’s an inline remote control with a single button that lets you control your music, as well as a microphone for making calls when connected to a smartphone.

As soon as we started listening to the S2s, it became clear that they’re incredibly well balanced for a pair of dynamic driver in-ears. The low end has real presence in rock and electronic music, but the crossover point ensures it doesn't intrude into the mid-range or overpower more delicate tracks. Getting a good seal is crucial, as without one the bass and treble performance drops off significantly. Thankfully there are so many pairs of tips included in the box that this shouldn't be an issue.

The mid-range and treble have a tendency to sound warm, most notably in the crash of cymbals or vocals. It never sounded harsh or sharp, though, even when playing some of our more technical acoustic tracks.

You also don't need to increase volume to maximum in order to hear the detail in a track, although the Fidelio S2 does admittedly need driving further than other in-ears we've tried.

The Fidelio S2 produces superb audio as long as you get a tight seal. Bass and treble performance are impressive for dynamic driver in-ears. However, you can buy the Fidelio S1s for much less, and they differ in construction and build quality rather than sound, and appear better value overall.