The Unique Melody Mage pack in no less than four balanced armature drivers, with two to drive the low end and two for the mid-range and upper frequencies. In contrast, the ACS T2 use two drivers while the Unique Melody Aero and past favourites the Shure SE535 use three.
Despite this mass of drivers the Mage are incredibly sensitive and easy to drive. We regularly found a single press of the volume button (from mute) on an iPhone resulted in too loud a signal for prolonged listening. Instead we'd have to use the volume slider to pick out a point half way between. Indeed, using some headphone amps that introduce some hiss, we had to employ a noise attenuator (inline volume control) so we could crank the volume and drown out the hiss. We do have particularly sensitive ears, though. If you do like to drive your ears to destruction the Mage will happily oblige without distortion, even when amped and cranked, but generally you can get away without extra amplification.
That said, adding a headphone amp into the mix does bring out the Mage's full potential. The bottom end tightens up sounding more precise and punchy while overall articulation is improved. This adds yet more detail and a wider sound stage to what is already an incredibly accurate sounding set of 'phones.
Looking at that sound in a bit more detail, this set is primarily sold as a one to appeal to lovers of detailed high-end, rather than booming bass. High frequencies simply sparkle bringing a huge amount of life to recordings of all types, all without sounding sibilant. Combined with the vast overall frequency range this particularly helps to spread the sound stage far and wide, making these one of the most expansive sets or IEMs we've ever used. Instrument separation is also stunning. From picking out the multi-tracking used to add beef to Dimebag Darrell's heavy metal guitar riffing to being able to almost count the number of 1st violins used in the intro to the "Nimrod" movement of Elgar's Enigma variations, no other IEM we've heard can match these.
Mid-range is also exceptional with guitars, piano, vocals and the like all coming through with real vigour and realism. This is somewhat similar to the ever popular Shure range but the Mage add handfuls of brightness as well, thanks to that sparkling top-end.
What you don't get with this set, though, is a huge thumping bass sound. Despite having the low end bumped up on our review set, these are still a fairly delicate set of IEMs. That's not to say bass isn't there. The range is vast with the lowest rumblings faithfully recreated, but it just doesn't hit you in the face. It sounds pretty close to perfect to our ears, providing bombast when called upon but not colouring the sound when daintiness is what's required. What's more it has an incredibly quick bass response, thanks in part to low-end responsibilities being shared between two drivers, meaning that while the hit from fast trance or heavy metal music isn't quite as hard as some alternatives the accuracy is all there.
The only complaint we have is that the boost that Unique Melody has applied doesn't appear to be entirely smooth, with it sounding just a little forced sometimes – like when a sub is set at too high a volume and suddenly kicks in when a note within its frequency range pipes up. It's a subtle thing and it certainly wouldn't put us off but it does make us doubly intrigued to hear the Unique Melody Merlin that use four balanced armature drivers and a dynamic driver to naturally provide a more bass-heavy sound.
It's also worth reiterating that we're judging these phones having asked for a bit of a bass bump, so if you want to match this performance you'll have to ask for similar. From our time with the default sound signature – bearing in mind the fit wasn't perfect – we'd suggest they are a little too lacking in bass for heavy metal fans in particular but also anyone that likes a thumping bass line. For classical, jazz and acoustic fans, though, they're excellent.
The Unique Melody Mage are quite simply the most sparklingly detailed set of In-Ear Monitors (IEMs) we've ever tested. Certainly for acoustic and classical music we've heard none better. In there natural state bass response is a bit light but, being a custom set, you can ask for this to be boosted and the result is a great all round sound. Indeed sonically these are among our favourite IEMs. Where they wobble a bit is with their construction. They're beautifully crafted and the choice of finished is astounding but the hard plastic shell, as used by most other custom IEMs, just can't match the comfort of the soft silicon used on the ACS range. For general listening this isn't an issue but if you'd like for your headphones to go with you everywhere, including for jogs round the park and when slumbering, then the ACS T2s may still be your best bet, though sonically they are a step down. We also wish a few more accessories were included in the box.
As to whether to go for custom or regular IEMs, if you get the fit right then nothing compares to the comfort, noise isolation and sound stage of a custom but when you can get the quad driver Westone 4, for instance, for around £300, the £555 required for the Mage is a bit eye watering. Nonetheless these remain one of the most competitively priced custom IEMs on the market in the UK and sonically they totally live up to their billing.