FiiO FD1: Rounding Out


Today we’re checking out one of FiiO’s newest releases, the FD1.

The FD1 pull its physical side from the FH1S sharing the same low profile, ergonomic shell with unique celluloid faceplates, 0.78mm 2-pin system, and snazzy cable. Where the FH1S was a 1+1 hybrid, the FD1 rolls with a single dynamic. What sets it apart on the specs sheet is the use of beryllium plating on the diaphragm, tech which is generally reserved for much more expensive products.

I’ve spent nearly a month with the FD1 and have come away quite satisfied with the performance on hand. Let us take a closer look, shall we?

What I Hear The FD1 has a strong low end with a focus on sub-bass over mid-bass. As a result the experience is quite physical with deep notes providing plenty of visceral feedback, though I would like just a hint more midbass emphasis to really dial in that punchiness, and add a smidge more warmth. Still, you can really feel the rumble in the subterranean bass notes on Massive Attack’s “Teardrop”. The piano chords are given a powerful presence too, lingering appropriately and perfectly backing the emotional performance from Elizabeth Fraser. Unlike some other reviewers, I also found this driver quite quick and snappy, easily tackling the rapid bass notes of Sepultura’s “Lobotomy”. Lesser earphones will smear individual hits lending to a very messy and one-note sounding track. The FD1 does a good job retaining clarity start to finish. It’s no slouch in the texture department either. The heavily textured and distorted bass on The Prodigy’s “World On Fire” sounds adequately dirty and low-fi.

The mid-range is pulled back compared to the rest of the frequency range with an upper mid lift that helps it retain presence. Vocals are clear and articulate with only the occasional track running into a mild veil from bass bleed, such as on Felt’s “Whaleface”. I found the presentation here best suited to male vocalists. Female vocalists can sound a little too aggressive at times, particularly those with particularly high pitched voices. K-Pop fans will probably want to heed this warning. While leaning towards a thinner sound, there is enough body to keep the FD1 from sounding lean and overly light. Sibilance is handled very well here. The FD1 doesn’t introduce anything that isn’t already there, and what is there is minimized considerably. This is very evident on Aesop Rock’s “Blood Sandwich” which is quite unforgiving of sibilant earphones. I’d say the FD1 goes toe to toe with the KB EAR Diamond in this aspect, which is very impressive. Timbre is similarly accurate too, though here it is a hint dry vs. the Diamond’s lightness.

Treble out of the FD1 is nice and clean sounding with a well-defined structure to notes. There is none of the splashiness I find common to inexpensive single dynamics present here. This makes listening to King Crimson’s live rendition of “Cat Food” a joy since it is heavy on cymbals that often sound splashy and loose through the wrong earphone. Again the FD1’s snappiness and control shines, with notes decaying quickly. It ensures the FD1 remains coherent and articulate, even when things get busy. My only complaint here is a lack of upper treble emphasis. This leaves the detailed lower treble to carry the upper ranges giving the FD1 it’s slightly dry tonality. There isn’t much sparkle to be found here.

When it comes to sound stage the FD1 again provides a satisfying experience. On Andrea Gabrieli’s “Communion: O sacrum convivium a 5” I get the impression I’m sitting a few rows from the stage. The layered vocals display impressive depth and width, temping me to turn my head to locate vocalists at either end of the procession. I had similar experiences using the FD1 while gaming and could fairly easily track enemies in PUBG as they moved around the house I was camping in, or to track shots of in the distance, helping me avoid combat when unwise to engage. While I find the FD1 to image, layer and separate quite well, I’m keen to try in on a game with truly advanced sound design, such as Hunt: Showdown which used binaural recording to craft it’s intense soundscape.

Overall I quite enjoy the way the FD1 sounds. The v-shaped tune on hand doesn’t do anything particularly new and exciting instead giving you a very competent example of that type of sound to point to. Bass depth is excellent with good control and texture. The slightly recessed mids can be a bit harsh with female vocalists, but sibilance is handled very well and there is plenty of detail on tap. Treble is also well done with great control and speed. There could stand to be a hint more emphasis in the brilliance region, but as is I found the upper ranges detailed and non-fatiguing. The sound stage is also quite good with plenty of depth and width on tap, backed by a layered feel and well separated instruments. Imaging is also decent too making tracking sounds crossing from channel-to-channel a mostly painless experience.

Compared To A Peer (volumes matched with Dayton iMM-6)

FiiO FH1S (85.99 USD): The FD1 has significantly more bass presence, though they both seem to extend similarly well. The FH1s’ low end lacks the punch and weight found on the FD1 leaving it to play a secondary role in the overall signature. Despite the lessened presence, it doesn’t feel any quicker or better controlled, with a similarly good texturing. Mids are more audibly forward on the FH1s with a leaner, less bodied presence, though they feel more spacious and spread out, almost to the point of being echoey. It is reminiscent of turning on a present EQ function. The FD1 sounds considerably more natural with more accurate timbre, though detail takes a step back. The FH1S is also more subject to sibilance and shoutiness, especially on female vocals, making it uncomfortable in instances where the FD1 is fine. Treble out of the FD1 lacks the extension and representation in the brilliance region, though it is cleaner and better controlled. Detail again goes to the FH1S though. Sound stage is notably larger out of the FH1S thanks to vocals that are set further back by default, a leaner note weight, and all that additional treble energy. That said, I prefer the cleaner imaging and instrument separation of the FD1, though it doesn’t sound as well layered.

Overall I think the FD1 is a pretty significant step up from the FH1S. It has a more refined, well-rounded tune without any of the midrange quirks, though those who liked the FH1S’ somewhat laid back bass might feel the FD1 is a bit heavy handed down low.

Shozy Form 1.1 (74.99 USD): The Form 1.1 has more upper treble emphasis providing more sparkle and shimmer than the FD1, though lower treble is comparable if not slightly more prominent on the FD1. Control and general refinement are in the 1.1’s camp. Detail and clarity go to the 1.1 though, in addition to sounding a bit tighter and cleaner on each note. Mids are slightly more forward out of the FD1. They’re more dry though, lacking the warmth and natural timbre of the 1.1, though I’ll give the FD1 a very light edge in terms of vocal detail. Bass out of the Form 1.1 extends well but rolls off before reaching the outstanding depths of the FD1. Balance is shifted towards midbass vs. the FD1’s subbass bias giving them very different presentations. I find the FD1 faster and more visceral with better texture, though the 1.1 has a more even mid/subbass balance leaving it feeling more well-rounded overall. Sound stage is wider and deeper on the FD1 with its generally more spacious feel being helped along by a less intimate vocal presentation. Imaging is similarly good while I find the Form 1.1 slightly more competent when it comes to layering and separating sounds.

Overall I find these two both quite good, though the 1.1s improved timbre quality and generally more balanced sound has me picking it up over the FD1 more often than not.

KB EAR Diamond (79.00 USD): These two I find quite comparable and similarly tuned. Extension from the FD1 is a bit better with a balanced shifted more towards sub-bass compared to the Diamond’s midbass hump that grabs your attention. The FD1 is more textured and punchy leaving the Diamond feeling a hint soft and overly smooth. Grungy textures lack the same animation heard through the FD1. The FD1’s mids are more forward and a bit thicker. Detail is similarly okay on both, with neither really having an upper hand. I also find both a little on the lighter side when it comes to timbre, though the Diamond is a bit ahead here. Neither seem shouty and both do an excellent job minimizing sibilance. Treble out of the FD1 is also slightly more forward and has a grittier texture to it. I prefer the Diamond’s presence/brilliance region balance with feels more even. While the FD1’s presentation is a little tighter and more detailed, I found myself preferring the Diamond’s more laid back, completely non-fatiguing treble. Sound stage goes to the FD1. While its default vocal positioning is closer to the ear, it does a better job tossing effects off into the distance, though depth is similarly presented. The Diamond always feels a bit closed in. This is somewhat beneficial in showing off imaging and separation qualities which edge out the FD1, though it falls behind when it comes to instrument layering.

Overall I find myself enjoying the FD1 more thanks to the additional texture, subbass emphasis, and more spacious presentation.

In The Ear The FD1 uses the same shell as the FH1s before it. The low profile design conforms to the natural shape of the outer ear providing a stable fit that is only helped further by the use of preformed ear guides. Those who have particularly small ears or outer ears with an unusual shape might have troubles wearing the FD1, but for the majority they should provide a comfortable wearing experience.

That’s helped along by the fact they are so light thanks primarily to the use of plastics for the construction. Fit and finish is excellent with tight seams between the inner half of the shell and face plate. The metal nozzles are glued neatly in place without any excess glue having seeped out. The 2-pin ports are slightly raised and about the only area of concern since I have seen numerous images of this style of port cracking. That said, the raise is fairly conservative with thick sidewalls surrounding the actual ports, so I have faith they’ll hold up. One aesthetic touch that FiiO rightly seems proud of is the layered celluloid face plates which are unique from model to model. This is apparently the same material used for guitar picks so durability should be very high.

FiiO always goes the extra yard with their included cables and the FD1’s is no exception. This cable is outstanding for a product under 100 USD, and I would have been plenty happy to see it included with something notably more expensive. The twisted design is thick but very flexible and not so weighty that it tugs at the earphones while you walk. The 90 degree angled jack in one that FiiO has been using for a while now and has ample strain relief in place to protect the cable. The plug also extends slightly to help ensure good fitment with a variety of phone and DAP cases. The FiiO branded metal y-split doesn’t have any strain relief, but with cables of this style and with splits this compact I’ve never found it an issue. Sitting just above the y-split is a compact metal chin cinch that moves with just enough resistance to ensure it stays in place while remaining easy to adjust when needed. Leading up to the 2-pin plugs that angle at ~45 degrees are preformed ear guides. Since FiiO went with shrink wrap instead of the hard plastic some manufacturers use, they remain flexible and soft but stiff enough to keep the cable from bouncing out of place. Another nice touch is the redundant left/right markings. On the inside of each plug is a small letter to denote the channel, while on the base of each plug is a coloured pad; red for right, blue for left. It is always nice when companies go out of their way to add various methods of determining channel. Shows an attention to detail that is sometimes lacking in the industry. The only complaint I have is that the plugs sit flush with the raised ports on the earphone instead of wrapping around them like you’ll see on similar designs from a few other manufacturers. Leaving this out means the pins are more easily damaged, but treat the product with a modicum of care (ex. use the case and don’t simply toss them into a pocket) and you shouldn’t have to worry.

Lastly, the FD1’s isolation is not amazing. I’d put it into the “average to slightly below” camp thanks to the reasonably shallow fit inherent to this particular shell design. There is also ample ventilation through a pinhole in front of the driver, and another cleverly hidden behind the 2-pin ports. On the plus side, wind noise is kept to a minimum which is cool. They’re definitely usable in noisy areas, but you may have to compensate with added volume (less so if you opt for foam tips).

In The Box The FD1 comes in the same magnetically sealed flip-top style box that the FH1S came in before it. On the front is an image of the left earpiece, as well as the usual branding and model information, as well as a Hi-Res Audio logo, set on a black backdrop. The rest of the package contains nothing noteworthy. Flipping back to lid you are greeted by a large manual within which you find information in the correct way to wear the FD1, how to property attach the 2-pin cables, as well as warranty information among other details. Lifting this out you find the FD1 set tightly within a cardboard coated foam insert. The cable is attached and neatly wrapped within a separate enclosure below. There is also a second, smaller cardboard box in which you find the accessories. In all you get:

  • FD1 earphones
  • 0.78mm 4 strand, 120 core, OFC Litz cable
  • HB1 carrying case
  • Small bore single flange tips (s/m/l)
  • Wide bore single flange tips (s/m/l)
  • Memory foam tips (m)
  • Velcro cable tie

In all a very satisfying unboxing experience. The tip selection is good with each style of tips offering a slight variation on the sound signature. They use decent quality materials too, though a little on the stiff side in my opinion. Still, they seal well and should be durable in the long run. The HB1 Pelican-style case looks great and has a rubber seal around the base where the lid rests which should offer some water resistance if you’re the type to take your earphones out in adverse weather or with you on a camping trip.

Final Thoughts The FD1 is a well-rounded earphone that is plenty competitive within it’s segment. It has an attractive, well-designed, comfortable shell with a high quality cable. Included are a wide variety of tips and sizes with a great Pelican-style case, though some might appreciate if FiiO included a smaller, more pocketable option too.

Sound is tuned with a familiar v-shape. Sub-bass steals the show, digging deep and providing plenty of visceral feedback with lots of texture and good control along the way. Mids could stand to be a hint more balanced, lacking emphasis but still a bit harsh with some female vocalists. Sibilance is very well-managed though and mostly absent. Treble is clean and well controlled with good detail, though the focus is clearly on the presence region. There isn’t a ton of sparkle to be had with the FD1, surprising given the reasonably vast staging present.

Unless you’re going in expecting something neutral, I can’t see too many being disappointed with what FiiO has released here.

Thanks for reading!

– B9

Disclaimer A big thanks to Sunny with FiiO for reaching out to see if I would be interested in covering the FD1, and for sending over a sample for review. The thoughts within this review are my subjective impressions based on nearly a month of use. They do not represent FiiO or any other entity. At the time of writing you could pick up the FD1 for 89.99 USD: /


  • Driver: 10mm dynamic with Beryllium-plated diaphragm +N50 magnet
  • Impedance: 32Ω@1kHz
  • Sensitivity: 109dB (1kHz@1mW)
  • Frequency Response: 10Hz~40kHz
  • Cable: 0.78mm 2-pin 4-strand high-purity monocrystalline copper

Gear Used For Testing LG Q70, Earstudio HUD100, Earmen TR-Amp, Asus FX53V, TEAC HA-501

Some Test Tunes

Supertramp – Crime of the Century

Slipknot – Vol 3 (The Subliminal Verses)

Daft Punk – Random Access Memories

Aesop Rock – The Impossible Kid

King Crimson – Lark’s Tongues in Aspic

King Crimson – Starless and Bible Black

Infected Mushroom – Legend of the Black Shawarma

The Prodigy – The Day is My Enemy

Steely Dan – The Royal Scam

Porcupine Tree – Stupid Dreams

3 thoughts on “FiiO FD1: Rounding Out

  1. Thanks for the review!

    I’m currently in the search for replacement for my twice soldered Sony MDR-EX500 which to me sounded like perfection incarnate, and this somewhat fit my budget. From what I gather, they could be a decent replacement.
    I’m a bit worried because those Sony with their 13.5mm drivers sounded very powerful, the sub-bass was oceanic, natural-warm in general, no hissing at all, and they could sound very loud with common iPods, but I gather the beryllium coating does wonders to make the drivers sound larger?

    I’m no audiophile at all, and I use my earphones for running and cycling, reading at night, long bus trips to another town (I can’t use “sports” earphones because all I’ve tried sound terrible, I don’t care about wireless, and I hate Bluetooth).

    If you could give me an opinion on whether they’d do as replacement I’d be very much obliged.

    Thank you!


    1. Never heard the EX500 so I can’t say if these would be a suitable replacement. The FD1 is a good product though and sounds like it would offer some similar aspects to the EX500 based on your comments. Maybe give the Jade Audio EA1 a look instead? They’re the same earphones as the FD1 but with a different cable and at a lower cost.


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