Drop + JVC HA-FDX1 Dual Carbon IEM...available in the US!
Aug 10, 2019 at 6:05 PM Thread Starter Post #1 of 1,363


Headphoneus Supremus
Mar 4, 2010
San Francisco Bay Area
Hello Everyone! VERY excited to make this post.

I'm able to announce our new collaboration with JVC:

We've been working hard to start getting some samples out and I'll update here more as we go (reserving some posts).

You will see some impressions here from community members, even before the pre-sale begins on 9/5/2019!
Aug 10, 2019 at 6:07 PM Post #2 of 1,363


Headphoneus Supremus
Mar 4, 2010
San Francisco Bay Area
Graphs from Jude! RAW, uncompensated. (With Harman Target for comparison.)




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Aug 10, 2019 at 6:36 PM Post #4 of 1,363


Headphoneus Supremus
Sep 25, 2010
What is the FDX1 and how is it different from (or the same as) the FD01?

The Drop FDX1 is essential the same as the FD01 with minor changes and community tuned filters.
  • Same dual carbon 11mm driver (DLC diamond like carbon inner dome and black carbon outer ring)
  • Same great pleather JVC magnetic case
  • Same great robust OFC cable; On the slightly thicker, heavier side, yet very soft and pliable; virtually memory free with excellent tangle resistance
  • Same CNC machined Stainless Steel housing minus the knurled ridges; housing is a two piece design that swivels to accommodate wearing up or down and any shaped canal
  • FDX1 ditches the Titanium and Brass nozzles and comes with 3 Stainless nozzles
  • 1 nozzle is empty for stock FD01 tuning and/or modding, and 2 nozzles contain community tuned filters
  • Spiral Dot + tips (the best wide bore tips on the market IME)
Pre-Sale starts 9/5/19 for $250. FDX1 will be $280 thereafter. Frankly, the FDX1 is a no-brainer at this pricing.


Most of us find the stock tuning of the FD01 to be too strident. In mid 2018, super friend community mod-wizard James444 presented us with detailed instructions (with measurements) on how to mod the removable nozzles of the original FD01. The results were a smoother, more even response that competed with in-ears double in price and more. The modded FD01 has natural timbre and tonality with great dynamics. It’s got the boogie without loosing the realism. The mod was a hit. Many community members purchased their own sets and began performing the mods to great satisfaction. A few even sold off their more expensive rigs.

Once I was able to perform the mods on a community loaner set myself, I was so excited with the results, I instantly started blowing up CeeTee’s phone with texts. He needed to hear this and he had to figure out a way to bring this to the masses. There was this one poor guy that loaned his set out to Drop; little did he know how long that loan would last but thank-god he did. I’m not sure how CeeTee and his team pulled this off, but somehow they were able to get JVC to the table and bring this thing to life.

The first set of prototypes weren’t really close but did show some promise. I was able to compare them with that poor guy’s well modded set. I think he’s been without it for close to a year now. His modded set was then sent to Japan, so the JVC engineers could hear what we were so in love with. The second set of prototypes nailed it. Again, I was able to compare to this poor guy’s set. They were extremely close to his DIY modded set! Was this poor guy going to get his set back now? Nah, a final comparison to pre-production models was going to be the required!

In early August, I sent James444 an email: IT IS HAPPENING. The pre-production model had arrived. While this time I don’t have that unnamed poor soul’s modded FD01 to compare, I knew the FDX1 was better. Somehow, someway, JVC had figured out a way to tighten the bass up. The slightly hazy bass of the modded FD01 was its biggest criticism. The FDX1 betters the modded FD01 with tighter, cleaner bass (this has been confirmed by a notorious purring cat friend, who compared the FDX1 to that same poor guy’s modded FD01). What was once a criticism is now a strength.


The two community tuned filters are more similar than different. Basically one sounds a hair smoother, darker (blue) and the other is more lively, energetic (green). The empty filter is ripe for the modding! In general, my preference is for the green set but I do enjoy the blue set as well, particularly on the go in noisy environs.

The FDX1’s dynamic driver excels in its more life-like timbre when compared to pricier all armature sets. It’s more even tuning also makes it more realistic sounding than the typically more colored and bassier dynamic driver offerings form the competition. Strings and percussion are the FDX1’s forte, highlighting low level nuances easily glazed over. While distortion rock guitars have solid crunch and bite, it’s the drums that I love to get lost in with the FDX1. Vocals are forward and intimate- male vocals are rich with heft, and female vocals are clear and energetic. Staging is better than average. While not as expansive left to right as Andromeda, it sounds open and effortless with a deeper reach front to back. While not as tall as something like Solaris, it’s sounds taller than the typical in-head, in-ear presentation. While single dynamic drivers usually don’t have the separation and layering of multi-armature or hybrid sets, they produce a more organic and natural sound. The FDX1 has plenty of space to breathe around individual instruments and singers, and it does it all while simply sounding effortless.

via SDAC>Liquid Carbon X (less than 1 ohm OI)
FDX1 with green filter and Spiral Dot tips

Massdrop Plus
(with Mee Audio dual flange tips)
  • Plus has a more diffuse field neutral target tuning
  • Plus has thinner overall note weight
  • Plus middle treble is more present for more brightness and sparkle overall
  • Plus bass tilted to deep bass; FDX1 sounds more balanced in bass with less emphasis in any specific area (deep, mid, upper) in direct comparison; however FDX1 bass feel more elevated overall and is more solid, palpable
  • Plus has quicker bass decay
  • Plus cleaner but less natural sounding
  • Plus vocal placement is similarly forward; male vocals sound thinner but female vocals have more energy than FDX1
  • Plus doesn’t have the same perception of depth; less space around instruments and performers; shorter stage in height
  • Plus transients are faster; distortion rock guitars have more bite and attack; FDX1 is smoother overall

(with Mee Audio dual flange tips)
  • Andromeda has noticeably faster transients; better attack; FDX1 sounds smoother, warmer
  • Andromeda sounds a good bit more natural than the Plus but still less so than FDX1
  • FDX1 bass is slightly thicker, denser with better texture overall; similar extension
  • Andromeda treble is overall brighter with better presence, better sparkle
  • Andromeda female vocals sound a little more blunted, huskier, less energetic
  • Andromeda is wider sounding, more upfront; similar height but slightly less depth and sense of space front to back
  • Andromeda distortion rock guitars sound bigger, bolder
  • Andromeda is more resolving of background details and treble resolution, whereas FDX1 sounds more nuanced and micro-dynamically resolving in decay of percussion and plucked/strummed strings
  • FDX1 sounds more dynamic and effortless from quiet to loud transitions; whereas Andromeda sounds more enveloping, more surrounding my head with a wall of music

Parting Thoughts

The modded FD01 has consistently been a recommendation from me, if a buyer is willing to perform the mods. I’ve long thought the modded FD01 was a bargain at $330-$380 imported from Japan at the time, but the FDX1, with it’s changes and factory mod applied filters, pretty much make it the biggest no-brainer I’ve seen in a long time. For anything less than a used/B-stock Andromeda, it will be my go to recommendation.
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Aug 10, 2019 at 6:42 PM Post #5 of 1,363


In the Happy Place
Nov 27, 2010
A Review… sorta. More like a few opinions and observations.

Good: Excellent resolution, neutral-plus tonality, dynamic driver bass, A+ hardware, and of course- tunability.

Meh: Nozzles just a tad on the large side, a bit heavy.

Given: Hardware is functionally identical to the FD01- Same cable, same fit, same isolation, same tip size- even the same carrying case.

tl;dr: $250 would be a great price for the stock FD01. The FDX1 is better. With the Drop deal you essentially get both with a quick nozzle swap.


Me: I’m an old guy. I have to take off my glasses to see things up close. I can't hear much past 14KHz. My first decent IEM was the Ultimate Ears Triple-Fi. I also grew up with stuff like the Monster Turbine Pro, Sennheiser IE8, a few random Sony and Audio Technica models, and the JVC HA-FX700.

Since most sound descriptions mean little without a reference point, I'll leave most of that information down below in the comparisons. And because the FD01 has been out for a while, I won't get into the common aspects of that and the FDX1. I will say that having only heard the FD01 once before this, I was quite surprised at how good of an IEM it is in stock form. But the modded filters really do seal the deal for me. In stock (FD01) form, it does run bright. Keep in mind that I am a life-long, card-carrying member of the Treble Head Club: I listen to my HD800s un-modded. I prefer the HD600 over the HD650. I don't know what all the fuss is about with ESS Sabre DACs. And so on.

One question that I've heard thrown around: "Is this the IEM version of the HD6XX?" In terms of SQ, it's hard to compare because to me headphones inherently sound different than IEMs. I would say that the FDX1 sounds a bit more analytical and forward than the HD6XX- perhaps more in the direction of the HD600/800. But the HD6XX's true claim to fame is value: For a while it cut the price of its non-Massdrop sibling in half. The problem with comparing the HD6XX to the FDX1 is that the former is still an HD650 at heart. On the other hand, while the FDX1 can be the FD01 if you use the included stock filter, by using one of the other tuned filters (which to many will be seen as mandatory) you are getting something quite different.

So again, is this the IEM version of the HD6XX? No. That would only be the case if the HD6XX were already modded. What you are getting here is a rather heavily-discounted version of an already excellent IEM that includes additional tuning from the manufacturer, with all that entails (QC, warranty, etc.). It's more like if Drop came up with an HD6XX-MOD and sold it at a very deep discount.

"Well, that's great. But can't I just do this mod myself?" Sure you can. Go ahead. Call me when you're done. I've re-terminated IEM cables, re-cabled headphones, built an amp or two, and have modded a few headphones. But I have yet to do any HD650 mods, despite even having bought a second pair. Go figure. Also, the way that JVC has done this (re-)tuning is a bit different from what I've seen within the DIY community. So not only will this have better quality control and consistency than most of us can guarantee; but it simply may not be possible to duplicate at home. Granted for DIY there is the element of self-achievement and everybody needs a hobby- right?. But most people would rather spend their time doing something else. This is sort of an easy one for me. Did I mention, this is also cheaper?

Compared to…

NOTE: Not all of these are meant as direct comparisons. Most of it is to give context to what I am hearing from the FDX1. I settled on the blue filter nozzle:
  • white = stock FD01/brightest/no dampening
  • green = somewhere in the middle/some dampening
  • blue = the least brightest/most dampening

Massdrop Noble 'X': I mention this IEM because not only are they from the same Drop 'house', tuned by the same folks, and around the same price; but it's one that many are familiar with. Tonally, there is no comparison between this and the JVC. The Noble was always just a bit too warm for me. The upper vocal registers (roughly between 2 - 4KHz) are a bit recessed, and it could also use a little more air. The JVC has good midrange presence and no shortage of air, even with the warmest (blue) filter. The Noble's bass, one of its strong suits, ends just a bit too quickly for me (has less decay) and doesn't have the sub-bass extension of the JVC. This is despite the Noble being a more bassy IEM overall.

Noble Savant: Tonally, this is somewhat close to the JVC. To many the Savant is a bit on the bright side. For me it is one of my references for tonality, with the understanding that it leans slightly forward and bright. But despite the tonal resemblance here, these IEMs sound very different. Treble clarity and air is far better on the JVC. Headstage on the Noble is a bit more of a wall of sound, while the JVC displays good depth and more distinct instrument placement. The Noble has more fundamental bass (~100 - 150Hz range), whereas the JVC is a bit more restrained in that area while extending further into the sub-bass region. Overall, the Savant is a bit more in-your-face and has a more simplified presentation; while the JVC is just a little bit better in almost every way- tonal linearity, headstage, and resolution.

Tin Audio T2p (Comply tip mandatory- they're way too vee without them!): This is my EDC. It has my ideal tonality, along with a nice amount of low-end grunt/fun-factor. Given that it's also a dynamic (dual-driver) it shares some characteristics with the JVC such as smooth tonal transitions, deep bass impact, and smooth treble. The overall presentation of the T2p is a bit warmer and smoothed over compared to the JVC. It is also more forgiving on bright recordings. (Remember… Comply tips!) The pay off with the JVC is literally in the details. Bass is quite similar between the two; but a bit more articulate and extended on the JVC. Instrument separation and sense of space is also better. Given the price delta between these two, this shouldn't be a surprise.

UPDATE 9/25/2019:
I recently lost and had to replace my Tin T2 Pro, and discovered that they made a few changes- most notably to the sound. The newer version, distinguishable by the different cable attachment location and finer nozzle screen, is noticeably brighter. There is more upper-midrange and treble- my ballpark guess is on the order of 4-5dB around 7kHz. Still, using the Comply tips (TSX-500 and TX-500), they sound good to my ears. But they are definitely brighter than what I was comparing the JVCs to before. Interestingly, I borrowed a friend's T3, and with the Comply tips they seem much closer to the older T2 Pro than my new T2 Pro. But I always thought that the T2 Pro and T3 sounded fairly similar.

BGVP DM6: I hear this as fairly neutral, with a slight upper-midrange recession. Bass is nicely articulated ala BA; but you're definitely not getting the extension or natural decay of the JVC. The DM6 also has a tiny bit of that grittiness inherent in many multi-driver balanced armature IEMs. This makes things sound a little bit warm (harmonically) and at times a bit crunchy. The JVC has that coherence often found in the better dynamic IEMs. This is a good example of the differences between multi-driver BA and single dynamic driver IEMs. The DM6 is fast but has a slight haze or harmonic warmth that some may find appealing. The JVC's bass extends further and it has more natural treble timbre. It also has more upper midrange as well as slightly better resolution. I like both IEMs; but I like the JVC a bit more for it's lack of coloration.

JVC HA-FX700 (modded tips): I thought I'd throw this in just because. Though very different sounding, there are still similarities in the naturally smooth treble, smooth tonal transitions, and deep-ish headstage (for an IEM). I would also say that they both prioritize vocals; albeit in slightly different ways. All of the JVC 'Woodies' that I have heard (FX500/700, FX750/850/1100, FW01) have a mid-bass bump that made them ideal candidates for modding since it's the single glaring flaw in what are otherwise excellent sounding IEMs. The FD01/FDX1 is a clear step away from those- almost going in the complete opposite direction with the (relative) brightness and more linear bass response. What has stayed the same or similar is the natural treble timbre (especially with the blue filter) and coherent sound that good dynamics are known for having. If you're looking for that warm, romantic sound that the 'Woodies' are known for, you won't really find that in the FD01/FDX1- for better or for worse.
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Aug 10, 2019 at 7:29 PM Post #6 of 1,363


100+ Head-Fier
Aug 7, 2014

Having had the regular FD01 plus other DDs such as IMR R1 Zenith and IE800, as well as planars (iSINE20) and BAs (Massdrop Plus and Audiosense T800), I'm genuinely intrigued by these, I just hope the spicy upper-mid emphasis was tamed now!
Aug 10, 2019 at 7:29 PM Post #7 of 1,363


100+ Head-Fier
Nov 26, 2014
Paris, France
Will follow with interest. Still use my FW01 regularly, with fondness.
Aug 10, 2019 at 7:39 PM Post #8 of 1,363


Headphoneus Supremus
Aug 25, 2004
JVC FDX1: Questions & Answers

Disclaimer: The modded JVC FD01, on which these new FDX1 are based, have been my favorite IEMs for more than a year now. No one should assume, that this is in any way, shape or form, an unbiased Q&A.

What’s your background with IEMs?

I’ve been an avid IEM collector for many years. In the heyday of my collector’s passion, I must have owned well over a hundred IEMs (I stopped counting at some point). I’ve since downsized my collection, but kept the ones I consider „essential“. That’s why I still have classics like the ER4S, EX1000 or UERM and can directly compare them with more recent IEMs.

I read you’re a fan of dynamic drivers?

Yup. While I have all sorts of technologically different IEMs in my collection, my preference has slowly, but steadily been shifting towards single DDs over the years . The reason for that isn’t easy to explain and I believe there’s quite a bit of „gut feeling“ involved.

Here’s one post, in which I tried to shed a little light on this topic:
„Well, the short answer is, that while I think that (multi-)BAs sound usually clearer and more resolving than DDs, I also think that the timbre of acoustic instruments tends to sound somewhat more artificial on BAs, when compared to DDs or live acoustic music.

To borrow a metaphor from photography: BA timbre reminds me of a slightly over-sharpened picture. Impressive, contrasty and eye-popping, but not necessarily all that realistic.

Still, note that this is first and foremost just a personal opinion. I arrived at it after years of listening to classical music with many different IEMs... DDs, BAs and Hybrids. And noticing a few things in the process: for instance, that I intuitively and predominantly would pick DDs for classical, whenever I had several different IEMs at hand. And that upon switching from DDs to BAs, I would always need some time to adjust to BA timbre. Whereas the adjustment would happen almost instantly, when switching the other way round from BAs to DDs.

Subjective anecdotal evidence, of course. However, it made me stop buying BAs some time ago, since I listen a lot to classical and found myself not using them much. I still like to audition BAs though, and find many of them (like the Andros and PP8) technically very impressive.

There are likely also several scientific aspects relevant to the perception of BAs vs. DDs, like differences in transient response, the amount of odd order distortion, or potential phase issues with crossovers. But that's a multi-faceted and very complex subject, that I still don't know enough about to make any bold claims.“

Another aspect not mentioned here, I think we’re just used to the sound characteristics of moving coil transducers. And that could very well be the reason why many regard them as more „natural“ than other driver types. Think about it, most home speakers and headphones are based on moving coil. And most recorded music is mixed and mastered with moving coil monitoring equipment. So, if you want to hear things „like the artist intended“, what would be more natural than choosing moving coil (DD) IEMs over others for music reproduction?

And you’re obsessively modding these DD IEMs?

I hope not obsessively so. But when I hear something like the stock FD01s, which sound 90% close to my idea of perfect, then I can’t help but try to go the extra mile.

That’s how the FD01 filter mod originated, and after some trial and error, I settled on those alcohol swabs as DIY-filters. Some of my best audio friends took up the mod suggestion and liked it. Well, and the rest is (audio community) history, a story that @shotgunshane has already, very eloquently, told in his review.

Ok, so the modded FD01 (and the FDX1) are "perfect" now?

Not quite. As always, the „extra mile“ turned out longer than expected. And like all IEMs, the JVCs come with compromises of some sort. There‘s still a bit too much upper mids boost over what I‘d call perfect. And bass falls just a tad short of the EX1000, which still have the best bass of all DDs I’ve heard. But overall, the FDX1 come very close to my ideal sound signature and are my favorite DDs out of those I’ve heard. Personally, I prefer them over some much more expensive DDs, like the Vega, Xelento and IE800S.

Back to the filters, what’s the deal with that hole in the middle?

Well, it’s there for a reason. In my modding experiments, I noticed that if dampers occupy the entire nozzle, they cause a slight loss of bass clarity and dynamics. Therefore I tried these tube-shaped dampers, and found they do the job just as well, but without that negative side-effect in bass .

How would you describe the sound signatures of all three filters?

First of all, the three filters differ only in upper mids and treble. But since we perceive sound signatures as a whole, the FDX1 also seem to get a bit warmer and bassier as you move from the white to the green and the blue nozzles.

The white nozzles have no damper and hence sound leanest in bass and most forward in upper mids and treble. They create an impression of very high resolution, but that’s partly due to what I call „fake detail“ (an overemphasis on high frequencies). They can also sound quite fatiguing with music that has a lot of energy in the boosted range, like the brass section of a classical orchestra in full blast. However, for low volume listening at nighttime, they may still prove useful. And last not least, they can easily be modded with DIY-filters if desired.

The green nozzles have been tuned after my recommendation for FD01 „reference filters“. I would describe the sound signature as well-balanced, with a tasteful slight bass lift and a touch of warmth. The mids are mostly neutral with a moderate upper mids bump. And treble is smooth, free of sibilance and non-fatiguing, but with good presence and extension. There’s no „fake detail“ with these nozzles, just very good clarity and resolution throughout the full spectrum. These are the most versatile nozzles in my book, and they sound excellent with a wide range of music.

The blue nozzles are just a smidgen more pushed down in the highs and sound more relaxed than the green ones, while clarity and detail remain almost the same. They're the most warm-ish and laid-back sounding nozzles, and also my favorites for outdoors, where a slight tilt towards the low end comes in handy.

But Head-Fi’s measurements show the white (empty) nozzle actually closer to their target than your „reference“ filters?

Yes, I’ve seen that. What can I say... with regards to upper mids and lower treble, I’d call that target into question. Most people who’ve heard the stock FD01 (or empty nozzle FDX1) would agree that upper mids are clearly too much forward. And that we really don’t need even more low treble in the sibilance range, like the Harman IE Target would suggest.

But in the end, FDX1 buyers will get three different pairs of nozzles and will just use the ones they like best. So, regardless of whether they prefer the Harman IE Target or a more downsloping signature in the high range, the FDX1 will come with a matching nozzle for them.

How about bass? Is it really better on the FDX1?

That’s a tough one. I’ve spent hours A/B comparing the FDX1 to the modded FD01, but without reaching a solid conclusion. However, the majority of experienced listeners who heard both, confirm tighter bass on the FDX1. And there are burst and impulse measurements that seem to back their assessment. Therefore I tend to agree with the majority, even though I personally didn't really catch a significant difference.

So, what’s your advice to current FD01/FD02 owners? Are the FDX1 a worthy upgrade?

Another tough question. It’s actually easier for me to answer that for FD02 owners, since you'd get a better cable and the option to swap nozzles. Plus, the micropore tape mod on the FD02 is less robust than the filter mod on the FD01, so the JVC-made filters on the FDX1 would be a more substantial upgrade in robustness for FD02 owners.

For owners of properly modded FD01s, the upgrade would obviously be a less significant one. Needless to say, the professional JVC-filters have excellent channel matching and could improve imaging compared to DIY-filters... particularly, if you don't have a measurement rig to ensure consistency of your work. As for bass... I’d probably say that those, who‘re satisfied with bass quality on their FD01, don’t have much reason to upgrade to the FDX1. But for those, who feel that bass sounds a little too loose on their FD01, the FDX1 might well be worth a try.

I’ve been thinking about buying and modding the FD01. Should I go for the FDX1 instead?

Are you kidding me? Why would anyone buy and mod the FD01 any more, if they can have the professionally damped FDX1 for less money instead? Thanks to @shotgunshane, @CEE TEE and the team, the FD01 filter mod should be pretty much obsolete by 9/5/2019!
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Aug 11, 2019 at 1:31 AM Post #10 of 1,363


Headphoneus Supremus
Mar 4, 2010
San Francisco Bay Area

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