The first time I heard the FD1, I knew it wasn’t just another cheap IEM designed to please the masses with a fun-tuned, bass-centric signature that dovetails with most modern music genres. Instead what I was hearing was decidedly unimpressive (and that’s a good thing, as I’ll shortly explain).
The FD1 is easy enough to drive from most devices, with an impedance of 32 ohms and an SPL rating of 109dB @ 1mW. The higher impedance means you’re unlikely to encounter any hiss from more powerful sources, and in my experience the background is indeed nice and dark with whatever I plugged them into.
That said, a well-implemented dynamic driver with a strong magnetic coil does benefit from extra juice, and I found performance (and sound quality) improved with more powerful sources. Also, while I’m not entirely convinced that miniature drivers benefit from mechanical ‘burn-in’, I did leave the FD1 connected to my music player for 24 hours to allow the driver to settle, and I encourage you to do the same in case there’s some residual ‘looseness’ in the sound at first listen.
The most interesting thing about the FD1’s sound signature is that no single frequency jumps out at you immediately. Unlike some IEMs that have big personalities off the bat – be they big and bloomy, bright and airy, or a mix of both – the FD1 comes across as even-toned, nicely balanced, with a sound that doesn’t try impose itself on the song. I daresay it’s an ‘audiophile’ tuning that lets each frequency stand on its own, without overlaying or interfering with other frequencies.
I wouldn’t call the FD1 completely ‘neutral’, because it does have a hint of warmth in the low-end and midrange that makes the sound a touch more accessible, and treble is by no means elevated or extended, though at this level that’s a good thing. I’ve heard too many cheap IEMs that try compensate for average technicalities by boosting treble to create pseudo-detail that’s just not there, and end up sounding harsh, sibilant and tinny instead. Thankfully, none of those terms can be used to describe the sound of the FD1.
The FD1’s bass response, or rather, it’s polite bass signature, is the first departure from many IEMs in this price class. While not the biggest dynamic driver in FiiOs line-up (the FiiO FH7 sports a 13.6mm beryllium-diaphragm driver), I was still expecting some hefty bass from the 10mm equivalent in the FD1. To be fair, the bass quantity is there, when called for, but bass is never imposed on a track if it’s not in the recording.
A good example is the kick drums in the intro to Brandi Carlile’s ‘The Story’. The drums give this track the feel of a live performance, and can be pretty potent with some IEMs and headphones, but while they’re present and accounted for with the FD1, they’re not quite as visceral as I’ve heard them. This could be because of the faster attack and decay of the driver membrane, or simply because FiiO decided to tune the bass with a deft touch. I suspect the latter, because the FD1’s bass reminds me very much of its big brother, the FH7.
What the bass lacks in sheer weight it more than makes up for in quality, speed and texture. I often return to ‘Trotto’ by Angels of Venice to get a ‘feel’ for the quality of the bass, most evident in the big drum hits on the track. The FD1 renders the drums with a great sense of texture and somewhat surprising speed. This is quality bass, make no mistake. It’s not overly loose, bloated or flabby, but it does bloom ever so slightly.
Daft Punk is another regular go-to for testing bass, and both ‘Contact’ and ‘Giorgio by Moroder’ are my go-to tracks from the band’s brilliant Random Access Memories album. Contact reveals the FD1’s sub bass chops with some nice rumble in the intro, though it’s not the most resolving or physical sub bass I’ve heard in an IEM ($60 reminder inserted here for good measure).
Mid bass is slightly more elevated than sub bass in Giorgio by Moroder, so the bass response isn’t completely linear, but that’s more a factor of tuning than it is the actual capabilities of the driver.
If you’re looking for an IEM to knock your teeth out with EDM and other bass-driven genres, the FD1 is probably not the one for you. It simply won’t satisfy your inner basshead, and frankly I don’t think it’s meant to. I felt the same way about the FH7’s bass response, and FiiO seem to have stuck to their guns in that regard. This is good, wholesome dynamic driver bass done right, and at a higher level than I’d expect from a $60 IEM. In fact, this is better bass than I heard in FiiO’s all-BA FA7, an IEM that costs $400 more.
Overall, the FD1 has a thoroughly satisfying bass response. I can trust it to deliver just the right amount of quality bass where the track calls for it, and it always maintains a sense of control, if not top-shelf resolution or tightness.
The presence region of the FD1 is clear and natural, without any obvious deficiencies. It’s not the most resolving midrange I’ve heard, but it’s not smoothing over obvious details in vocals and instruments either.
Both male and female vocals are well presented here. Neither are as full and natural as I’ve heard on other (far more expensive) IEMs, but also better than I’ve heard on many IEMs that cost significantly more than the FD1.
Heidi Talbot’s sultry vocals on ‘If You Stay’ and ‘Cathedrals’ (In Love and Light) are smooth, quite full, and not at all sibilant. There’s a touch of upper midrange elevation that can sometimes make higher-pitched female vocals sound shouty, but the FD1 just about manages to avoid that pitfall.
Ian Anderson’s vocals on Jethro Tull’s ‘The Waking Edge’ are balanced, with ample weight, though perhaps missing a touch of character and emotion. The same goes for the vocal chorus in Def Leppard’s ‘Love Bites’, even though I’d classify them closer to the female vocal range. While free of sibilance (a common issue with this track on brighter IEMs), the vocals aren’t particularly full either.
Guitars and pianos have excellent timbre throughout, and are also fairly lifelike. Nils Lofgren’s strumming in his live rendition of ‘Keith Don’t Go’ is super clean, with natural decay and zero harshness, though it does lack the last mile of detail. I wouldn’t call the FD1’s mids recessed, because they’re not, but they are set back a touch from the treble, which is apparent in the slightly masked female vocals in Owl City’s ‘The Saltwater Room’.
Midrange is usually the hardest frequency for a single dynamic driver to render consistently, and while the FD1 has its shortcomings in this region, it has more strengths than weaknesses, and importantly avoids the harshness, forwardness and sibilance that has spoiled many an IEM in this price range.
Treble is where the FD1 will rise or fall in many people’s estimation, and it basically comes down to preference. I personally feel the highs of the FD1 is where the beryllium-coated membrane returns the most value. The sheer speed of the driver keeps the treble from distorting, and it consequently never comes across as harsh, grating, strident or thin.
It is rolled off, however, so don’t expect the FD1 to have as much air up top or as much space between instruments as more brightly-tuned IEMs. Joe Satriani’s epic guitars on ‘Always With Me, Always With You’ are a good example of the FD1’s treble strengths and weaknesses. While the tone is great, you’re not going to get the crunch of more resolving or treble emphasized IEMs – which can actually be a good thing if like me, you’re not the biggest fan of grating guitars.
That track does show up the slight rolloff in upper treble though, and the highest of highs of the thinnest strings aren’t entirely present. Leading edges are ever so slightly soft, but conversely this lends itself to a more relaxed, less fatiguing listen over longer periods.
Max Richter’s ‘Winter I’ is my go-to test for treble resolution and speed in string instruments. Here the FD1 sounds decently full, and also fairly fast, with the strings displaying nice texture and no harshness. That said, the track lacks some air between the instruments, and there’s a touch of looseness in the lower ranges that masks the treble in the latter parts of the track.
I’m not a treblehead, nor do I enjoy a bright signature, so the FD1 caters more for listeners like me than it does for those who want aggressive highs. Resolution is good, though not excellent, but that’s to be expected, especially without the help of a finely detailed BA driver.
I actually prefer the FD1’s treble tuning to that of the FH7, but only because I don’t mind sacrificing some detail and extension for a fuller, warmer sound. The FD1 is by no means a dark IEM, I’d even say it’s brighter than darker on the spectrum, but its total lack of harshness is something I personally appreciate and can listen to all day long.
Sound impressions continue on Page 4