For larger views of any of the photos (1200 x 800) - please click on the individual images

INTRODUCTION

Every so often as a reviewer you get a surprise – something not quite expected. Sometimes its disappointment – when a much hyped new product simply doesn't live up to its billing. Other times its quiet wonder and amazement – especially when something arrives that you thought would be just another product – and it turns out to be something quite special. When Sunny approached me about reviewing their F1 and F3 IEMs, my initial reaction was “OK its FiiO but I really don't have time to do an in-depth on another budget offering”. I'm glad it was FiiO because I would have been tempted to say no (my external work-load has been very heavy lately) to another company. But FiiO have supported my reviewing since day 1. I simply don't turn them away. This is one of those times when the voyage of discovery was also one of delight.

ABOUT FiiO
By now, most Head-Fi members should know about the FiiO Electronics Company. If you don’t, here’s a very short summary.

FiiO was first founded in 2007. Their first offerings were some extremely low cost portable amplifiers – which were sometimes critiqued by some seasoned Head-Fiers as being low budget “toys”. But FiiO spent a lot of time with the community here, and continued to listen to their potential buyers, adopted our ideas, and grew their product range. That product range now includes some extremely proficient DAPs, DACs, amps, and recently some earphones and IEMs.

FiiO’s products have followed a very simple formula since 2007 – affordable, stylish, well built, functional, measuring well, and most importantly sounding good.

DISCLAIMER
The F1 IEM was provided to me free of charge or obligation as a review sample. I thank FiiO for their generosity. I own and have paid for the E7, E9, E11, E11K, X1, and X5 in the past. I am not otherwise affiliated with FiiO in any way, nor do I make any financial gain from my contributions, and this is my subjective opinion of the FiiO F1 IEM.

PREAMBLE - 'ABOUT ME'. (or a base-line for interpreting my thoughts and bias)

Spoiler: Click here for a summary of my known bias

I'm a 49 year old music lover. I don't say audiophile – I just love my music. Over the last couple of years, I have slowly changed from cheaper listening set-ups to my current set-up. I vary my listening from portables (including the FiiO X5ii, X3ii, X7, LP5, L3, and iPhone SE) to my desk-top's set-up (PC > USB > iFi iDSD). I also use a portable set-up at work – usually either X3ii/X7/L3 > HP, or PC > E17K > HP. My main full sized headphones at the time of writing are the Sennheiser HD800S, Sennheiser HD600 & HD630VB, and AKG K553. Most of my portable listening is done with IEMs, and lately it has mainly been with the Jays q-Jays, Alclair Curve2 and Adel U6 (although I am spending more and more time with a pair of FiiL Diva lately). A full list of the gear I have owned (past and present is listed in my Head-Fi profile).

I have very eclectic music tastes listening to a variety from classical/opera and jazz, to grunge and general rock. I listen to a lot of blues, jazz, folk music, classic rock, indie and alternative rock. I am particularly fond of female vocals. I generally tend toward cans that are relatively neutral/balanced, but I do have a fondness for clarity, and suspect I might have slight ‘treble-head’ preferences. I am not treble sensitive (at all), and in the past have really enjoyed headphones like the K701, SR325i, and of course the T1 and DT880. I have a specific sensitivity to the 2-3 kHz frequency area (most humans do) but my sensitivity is particularly strong, and I tend to like a relatively flat mid-range with slight elevation in the upper-mids around this area.

I have extensively tested myself (ABX) and I find aac256 or higher to be completely transparent. I do use exclusively red-book 16/44.1 if space is not an issue. All of my music is legally purchased (mostly CD – the rest FLAC purchased on-line). I tend to be sceptical about audiophile ‘claims’, don’t generally believe in burn-in, have never heard a difference with different cables, and would rather test myself blind on perceived differences. I am not a ‘golden eared listener’. I suffer from mild tinnitus, and at 49, my hearing is less than perfect (it only extends to around 14 kHz nowadays). My usual listening level is around 65-75 dB.

For this review – I've used the FiiO F1 out of most sources I have around me – from the higher end X5iii and X7 to the more budget X1ii. For the majority of the review though, I've simply used the X1ii and my iPhoneSE, as its likely to be the common smart-phone and lower end DAPs which are paired with the F1. I haven't used extra amping – as during my testing (we'll cover that later), I didn't find they needed or even benefited from additional amping. In the time I have spent with the F1, I have noticed no change to the overall sonic presentation (burn-in), but am aware that I am becoming more used to the signature as I use them more often (brain burn-in).

This is a purely subjective review - my gear, my ears, and my experience. Please take it all with a grain of salt - especially if it does not match your own experience.

THE REVIEW

PACKAGING AND ACCESSORIES
The FiiO F1 arrived in a compact white retail box measuring 97 x 168 x 42mm. The box is a simple but elegant white, with a picture of the F1 on the front cover, and specifications and features on the rear.

Front of the retail case	Rear of the retail case	In profile

Opening the box reveals a pull out tab, and this slides out the inner box, protected by a frosted plastic cover. Under this, nestled in a foam cut-out is the FiiO F1. Adjacent to the foam holder is an internal box which reveals a really nice carry case (containing the tip selection). Also included is a warranty document.

Inner sleeve	First look at the F1	F1 and accessories

The carry case is small, zippered, and semi-hard covered. It measures approx 75 x 85 x 35mm and is an ideal size for portable use. The outside shell is quite rigid and has an attractive carbon fibre pattern on top and bottom. Inside is a simply cloth internal covering with a mesh pocket. The quality and protection though is extremely good – I wish I had a dozen of these!

Tips and case	The (IMO) excellent case	Nice fit and still compact

The tip selection is simple, but remember we are talking about an IEM I've already seen on line priced between $15-$20. You get 4 pairs of silicone tips, and that’s pretty much it – but at this price point I really wouldn't expect anything else – especially considering the quality of the case.

TECHNICAL SPECIFICATIONS
(From FiiO)

	FiiO F1
Cost	Approx USD 15-20.00
Type	Single dynamic inner ear monitor
Driver Type	Dynamic 9.2mm
Frequency Range	20Hz – 20 kHz
Impedance	16 ohms
Sensitivity	97 dB / mW
Jack	3.5mm gold plated – right angled
Cable	1.3m fixed OFC with Polyurethane outer coating
Weight	18.6g
IEM shell	Industrial grade polycarbonate

FREQUENCY GRAPH
The graphs below are generated using the Vibro Veritas coupler and ARTA software. Ken Ball (ALO/Campfire) graciously provided me with measurement data which I have used to recalibrate my Veritas so that it mimics an IEC 711 measurement standard (Ken uses two separate BK ear simulators, we measured the same set of IEMs, and I built my calibration curve from shared data). I do not claim that this data is 100% accurate, but it is very consistent, and is as close as I can get to the IEC 711 standard on my budget.

The graphs are provided merely as a point of discussion, and later in the review I've included comparisons to other IEMs for similar reference.
 

What I’m hearing from the FiiO F1:

1. Reasonably natural sounding mid-bass with a slight hump, and pretty good extension (some natural roll-off into sub-bass). Sub-bass is reasonably robust, but still balanced with the rest of the overall signature

2. Relatively flattish lower mid-range, maybe the slightest recession or distance in vocals, but it is minor, and adds to the impression of staging size

3. Upper mid-range has a rise in the presence area (2 kHz) and gives a clear and clean vocal presence. It is around 10dB above the fundamental range at 1 kHz.

4. Lower treble is present but subdued compared to upper mid-range. Lower treble rolls off early and there is not a lot of presence from about 7 kHz onward.

5. Upper treble is quite rolled off

6. Overall it is a very slightly V shaped monitor with shallow peaks in the sub-bass and upper mid-range areas. It does feel more balanced than anything though – and the overall impression is quite vocal / mid-range oriented, and very smooth.

One thing to note is the extremely good matching of left and right channels. This is amazing from a $20 monitor! Well done FiiO.

BUILD QUALITY / DESIGN
External

Inner face and angle of the nozzle	Nozzles and vent	From the rear

The FiiO F1 body is two piece industrial grade polycarbonate (very hard plastic) which is squarish in shape with rounded corners. The plastic is very slightly translucent. The body is pretty small too – just 13mm across at it's widest point with a depth of about 12mm.. it looks kind of blockish, but is surprisingly comfortable to wear. The internal surfaces are pretty well rounded. If worn cable down, the nozzle extends slightly forward. It is approx 6-7mm in length with a generous lip (great for tips) and approx 5mm in diameter. There is a small dynamic driver vent adjacent to the nozzle exit. There is an approx 10mm arm which runs perpendicular to the IEM body – and houses the cable exit. This is capped with a rubber strain relief. There are L/R markings on the strain relief – but they are very difficult to see. The easiest way to remember left from right is that the control unit sits on the right hand side of the cable.

The cable
The cable is permanently fixed to the FiiO F1. It is OFC with a Polyurethane outer coating. The cable is an attractive black with very thin red highlighting. It is also very smooth, very supple, and exhibits reasonably low microphonics. FiiO chose the coating because it is lightweight, durable, and highly elastic. As soon as I saw the cable – my immediate thought was “Dunu” - more on this in a second.

Very faint L/R marking	Very good strain relief	The 3 button remote/mic

The cable has an in-line microphone and control unit extending from the right ear-piece approx 125mm from the cable exit. This unit hangs just under my jaw when worn over ear (so ideal height for the mic for me). The three button control unit has a central button for track controls (allowing play/pause (one push), next track (two pushes), and previous track (three pushes). The other two buttons are volume control buttons. Unfortunately they do not work with my iPhone, but they do work perfectly with my wife's Android Galaxy (S3 – she's an old fashioned girl) – and also with FiiO's newer DAPs – the X1ii and X5iii (they surprisingly won't on the X7). The microphone is surprisingly good quality – I had no issues with phone calls or activating Siri when using my iPhone.

The cinch (not a big fan)	Y-split	Looks familiar? Dunu style jack and cable tie

The Y split is located around half way down my chest, and just above this is the small cinch. Its really good for FiiO to include this – but they've gone with one which is permanently fixed on one side, but detachable on the other. It's not a bad design – allowing you to cinch above or below the mic/control unit. But because of the detachable side, it doesn't stay attached – the slightest pull and it releases. The first thing I do following the end of the review is going to be fixing it permanently to the other side of the cable as well. There is no strain relief on the y-split, but given the quality of the cable, the cost of the IEMs and the fact that the y-split is a semi-rigid rubber, I think omitting relief isn't a deal breaker.

The cable terminates at a 4 pole right angled gold plated 3.5mm jack with very good strain relief. The jack casing is relatively smart-phone case friendly (for my case anyway). Just above the jack – and able to be slid up or down the cable is a very familiar rubber cable tie. When not in use it sits unobtrusively close to the plug (I never notice it). When you’ve finished listening to the F1, simply carefully coil the cable and use the tie. Simple, elegant, brilliant.

So lets address the “elephant in the room”. The cable, the jack and especially the cable tie are all extremely familiar to me. Why? Because they are based on Dunu's designs – so I'd suggest they've had a big hand in the overall design of the F1 (which is a good thing).
 
Internals
FiiO makes special mention of this in their documentation, so I thought I should too. The driver utilises an ultra-lightweight polyester diaphragm – which FiiO chose because of its “relaxed tonality” which they've observed “works well with modern pop music”. Paired with this is a copper clad aluminium voice coil which has very good detail retrieval. Combined, the two are supposed to deliver a detailed, but fatigue free listening experience.

FIT / COMFORT / ISOLATION
I have one ear canal slightly different to the other one (my right is very slightly smaller) - so I tend to find that usually single silicon flanges don't fit overly well. I initially tried the included large silicone tips, and I was unable to maintain a constant seal (my difficult ears). I then switched to my after-market tips.

Spinfit and Ostry tips	Crystal foam and Trinity Kombi (Sony Isolation)	Shure Olive and Spiral Dot

The FiiO F1 easily fits most standard tip choices including Ostry tuning tips, Spin-fits, Spiral Dots, Comply foams and Sony Isolation / Trinity Kombi tips. I have a specially stretched pair of Shure Olives which tend to fit most earphones I'm reviewing, give me excellent comfort and seal – so I used them for the review.

I think FiiO probably designed these to be worn cable down (hence the 45 degree forward angled nozzle), but I was able to successfully wear them “cable over ear”, and the comfort was still pretty good with theShure Olives. There was one slightly hard edge – but with a little management (fiddling) this soon disappeared. The Fi is one of those IEMs which because of its size tends to disappear when worn. They sit well within my outer ear and are easy to sleep in.

 

Isolation with the F1 is about average for me and do a good job of passive isolation. However I wouldn't be using these for long haul transport.

SOUND QUALITY
The following is what I hear from the FiiO F1. YMMV – and probably will – as my tastes are likely different to yours (read the preamble I gave earlier for a baseline). Most of the testing at this point (unless otherwise stated) was done with my FiiO X3ii + E17K as source, and my Shure Olive tips. The reason I chose to go with the X3ii and E17K is simply because I know the combo so well.

For the record – on most tracks, the volume level on the X1ii was around 20 which was giving me an average SPL around 65-70 dB. Tracks used were across a variety of genres – and can be viewed in this listhttp://www.head-fi.org/a/brookos-test-tracks.

Relativities

1. Sub-bass – generally reasonably well extended, with normal minor roll-off associated with most dynamic drivers. The sub-bass is a little more emphasised than mid-bass and the curve peaks around the 50Hz mark. Relative to the rest of the freq range, sub-bass is elevated above mid-bass and lower mid-range, and has roughly equal SPL as upper mid-range. There is sufficient rumble present to represent lower notes well – but it doesn’t feel overly muddy or too bassy.

2. Mid-bass – still has a mild hump (necessary to sound natural) but is slightly recessed against sub-bass, and slightly elevated compared to lower mid-range. It is in effect a very gentle mid-bass bump, but also nicely distributed. The result is a very natural sounding bass response – and there is no noticeable bleed into the mid-range. Both mid and sub-bass are elevated compared to lower mid-range.

3. Lower mid-range – recessed compared to bass and upper mid-range. There is a slight sense of distance with male vocals – more-so than with female vocals. I have found myself upping the volume slightly – particularly with male dominated rock tracks. Pearl Jam actually sounded pretty good – although Eddie’s vocals could have used just a little more richness or fullness.

4. Upper mid-range – elevated compared to lower mid-range, and there is a reasonably significant rise from lower mid-range to the peak at about 2 kHz. The result is a clean and clear vocal range, with good presence to lend a very good sense of euphony to female vocals. The upper mid-range on the F1 is one of the best qualities of this IEM for my particular tastes. Even though the rise at 2kHz is about 10dB above the fundamental lower mid-range, it does not sound too strident – mainly due to the comparatively recessed lower treble.

5. Lower treble – present through to about 6-7 kHz and then drops away quite dramatically. This leaves a quite mid-forward but smooth overall signature. The only issue I have with the F1 for my tastes is that they are quite subdued, and could use a little bump (IMO) at around 6-7 kHz. Cymbals are still present – but subdued, and there is not a lot of air, or great sense of decay.

6. Upper treble – not really present .

Resolution / Detail / Clarity

1. Reasonable with micro detail, and still has ability to resolve many finer details well, but they are often subdued.

2. Cymbal hits have reasonable initial presence, but decay is somewhat lost due to the recession of the upper treble (especially around the 7 kHz mark).

3. A relative clean and clear monitor with average resolution but overall portrayal is decidedly on the smooth and warm side (mainly through lack of lower treble than over-done bass).

Sound-stage, Imaging

1. Directional queues are decent, and presentation of stage is just on the periphery of my head space with binaural tracks – so good sense of width and depth.

2. Spherically presented sound-stage with above average impression of overall depth

3. Absolutely compelling sense of immersion with the applause section of “Dante's Prayer” – and sounded very natural. “Let it Rain” was next up and because of the lack of lower treble emphasis, there was no sense of sibilance. I thoroughly enjoyed the F1 with Amanda Marshall’s album – and it was the smooth easy-going signature which really ticked my boxes here.

Strengths

1. Good overall bass response and the sub-bass is tastefully done without dominating. I think FiiO’s target range (younger generation modern music lovers) will love the default tuning.

2. Decent (if a little distant) with male vocals, better with female vocals, lending a slight air of euphony and sweetness.

3. Overall smooth and effortless with good vocal presence. Will suit those who like their music presentation with a warm, rich and smooth overall presentation.

4. People who like to listen a little louder may find the F1 ideal – without raising too much listening fatigue.

Weaknesses

1. Lower treble is under-done a little, and anyone looking for a very detailed listening experience may need to look elsewhere. Cymbals in particular lose their natural decay.

2. Vocal fundamentals can tend to sound a little recessed – mainly with some male / lower mid-range oriented music

3. Not the best at low volumes – detail tends to get a little lost.

AMPLIFICATION REQUIREMENTS
The FiiO F1 with its relatively low impedance and higher sensitivity is extremely easy to run straight out of your average source. With the FiiO X1ii I tended to stay around 20-25/100 depending on the track recording quality. With my iPhone SE – this translated to 25-30% volume.

Great with my iPhone SE (but no vol control)	Really good with FiiO's X1ii - and controls work fully	No real amplification improvements to these ears

I tried the F1 with the E17K, and there was no increase in dynamic presentation or elevation of detail to my older and somewhat insensitive ears. Even using DAPs with a lot more power (X7, X5iii, Cayin i5) didn’t really make a huge noticeable difference. So I think I’m pretty safe in saying that the F1 doesn’t need, nor benefits from, any additional amplification.

EQUALISATION
You've may have guessed at what I think could change on the FiiO F1 (at least for my tastes). Yep – elevation in the lower and upper treble. No sense in being too shy with this one, so using the EQ on the X1ii, I raised both the 8k and 16k sliders by 6dB and for my preferences this was an improvement overall. After that it was a matter of simply tweaking the 400k, 1k and 3k sliders by small degrees to get the overall vocal presentation to my liking. The good news is that there is definitely enough lower treble presence to coax some extra life via EQ.

COMPARISONS
This is not a price point I've really got a lot of experience with, so please excuse my lack of popular comparative IEMs. I have to work with what I have though – so for this comparison it is FiiO's own F3, RockJaw's Arcana 2 and Brainwavz's Jive and XF200.

As always, I first volume matched with a 1 kHz test tone and SPL meter. I had a fast switch set-up in place with a splitter and volume attenuator for the volume matching. This section is very subjective, as it is sighted, the change between IEMs took about 5 seconds, and I knew exactly which one I was listening to. But it is my honest thoughts on where the F1 sits for my own personal tastes. Source used was the E17K / X3ii combo – with no EQ (simply because it is still the source I know best).

FiiO F1 ($15) vs FiiO F3 ($25)

Frequency response	F1 vs F3

Both have similar builds, fit, and accessories – with the main difference being the changeable face-plates and inclusion of the ear-hooks. For me the F3 fits a little better because of the slightly smoother internal face.

Sonically both are on the slightly V shaped side of neutral with warmish sounding bass which is more centred toward sun-bass than mid-bass. The F1 has more of an upper mid-range peak which really helps vocals stand out. But after that it drops off pretty sharply. The F3 has less mid-range dominance, and more lower treble presence. Both are really good earphones for the price. For my personal preference the F3 is worth the extra outlay.

FiiO F1 ($15) vs Brainwavz Jive ($28)

Frequency response	F1 vs Jive

The Jive wins on overall build quality – but I like the cable on the F1 a lot more. Accessories are about even. Fit is good on both – but the Jive's diminutive size makes them slightly more comfortable.

Sonically the Jive is very V shaped comparatively – with a lot more sub-bass, a lot more treble extension, but also a quite comparatively recessed lower mid-range. If you were looking at the strengths of each, you'd be saying fun and lively vs clear and smooth. Personally I preferred the more balanced approach of the F1.

FiiO F1 ($15) vs Brainwavz XF200 ($25)

Frequency response	F1 vs XF200

The XF200 is technically more of a sports earphone – but they sit close to the same price range (so why not). The build, fit and ergonomics are all subjectively better on the F1. The XF200 can appear slightly blocky (I like the naturally formed ear-loops though). The F1 just feels sturdier though, and once again the FiiO (Dunu) cable is an improvement.

Sonically the XF200 is quite similar to the Jive. More of a V shape with extra sub-bass, comparatively recessed mid-range, and more emphasis on the upper mids and lower treble. The F1 is again smoother and more balanced – its just a bit shy on the lower treble. Again my preference here would be the FiiO.

FiiO F1 ($15) vs RockJaw Arcana V2 ($40)

Frequency response	F1 vs Arcana

I chose this one simply because the Arcana V2 impressed me when I first heard it. Like the FiiO it was a warm and smooth sounding earphone – but with a good sense of lower treble detail.

Build and fit are pretty good on both – but again the FiiO/Dunu cable stands apart. Overall on build, I'd give the slight nod to the F1. Accessories go to the Rockjaw (tips) but to the F1 for its case.

The Arcana still is a warm and lively earphone, and although I don't usually gravitate to this type of signature, there is something about the mid-range which can still captivate. That sub-bass is still a bit over the top though and I think that is where FiiO got it right with the F1. The bass has enough oomph to satisfy, without over-doing it, and then having to over compensate. Once again the F1 is my preference (but I wish they had just a little more presence around 6-7 kHz)

FiiO F1 - SUMMARY

Its not often I get to review something in this price range, and when I do it can sometimes be a pleasant surprise at how good audio quality can get for the price of a decent cup of coffee and a fresh baked snack.

The F1 has its good points and its not so good. Build is primarily plastic, but they are light-weight, and appear to be reasonably sturdy. The cable is the stand-out – good overall quality, and when you pair that with the case, there is more on the positive side of the slate than the negative. Fit is pretty good. Because of the angle of the nozzles (I suspect they are more for wearing cable down), it's not 100% comfortable – but good enough over-ear for causal use.

Sonically the F1 has good channel matching, is relatively well balanced, very clear through the vocals, and has nice cohesion between lower and upper mid-range. Its weakness is the roll-off in both lower and upper treble. This is clearly intentional and results in a smooth but clear IEM which will no doubt appeal to many people.

If I was going purely on build and sound, then the F1 would be a nice 3/5 in the budget stakes. But when you factor in the low price of $15 (how do they do it?), it becomes a 100% easy recommendation. I really enjoyed it. Well done FiiO. Recommended as a budget option.

Once again thanks to FiiO for sending me an evaluation sample.