[chickenmoon]

FWIW, here are Crinacle's and my own measurements of the stock (white nozzle) FD01/X1 compared to the Sony EX1000, another benchmark IEM for neutral bass:

His graph is RAW and mine DF-compensated, that's why the high frequencies look different. But from deep bass up to 1kHz, the measured response is very similar and shows the FD01/X1 as slightly bassier than the EX1000.

Personally, I believe it's actually the FDX1's upper mids / lower treble bump that makes perceived bass sound possibly less impactful than what the graph would suggest. That bump is a bit of a weakness in my book, and the damping filters succeed in flattening it a little, but aren't able to iron it out completely.

However, in a zoomed-in detail of said range, one can see that the FDX1's (green) unevenness is actually very benign, compared some typical BA peaks and dips (black + red). That's why it sounds pretty smooth in the highs, and I personally don't think there's a lot of masking going on in that range with the FDX1.

I've measured both EX1000 and FD01 myself and found the latter to have less bass but I should redo them to make sure.

As for "masking", here is, I believe, one good example at 3:41 in this track . To my ears, the JVC spectacularly fails to clearly convey what actually goes on due to its upper midrange brightness bleed.

 

[chickenmoon]

I still haven't received mine yet but am not sure if i would like them now. From all of your DD iems which one in your honest opinion would you say does mids, soundstage and clarity best overall? I still have the opportunity to return the fdx1 back as I haven't received them yet. Was really hoping that these would be the real deal.

I doubt you're going to love these but I honestly don't know what to recommend as you've got already all the usual suspects I believe.

 

[BrokeSkoolBoi]

Of course I'm traveling and left all the filters at home because I like the slightly damped the best, but I can't hear the bass range over all the bumping on the road! Whoever said the most dampened filter is best for traveling they are definitely right

 

[vessel]

Since Kanas Pro is a good reference point to me I asked a guy who already got his pair on Reddit if he could compare the FDX1 bass to the KP's bass, and that was the answer:

I have both, the FDX1 has more detail but less pronounced bass to my ears. That's with the most dampening. From my perspective they are both great but the FDX1 is a noticeable improvement and the more listen the better it sounds. The FDX1 is also more comfortable.

 

[james444]

I've measured both EX1000 and FD01 myself and found the latter to have less bass but I should redo them to make sure.

Yup, please make sure, because if your FD01/X1 has less bass than the EX1000, then we're obviously talking about different sounding IEMs.

Btw, I've listened to your example with my modded FD01 both as is and EQed down in upper mids. Of course I can hear the difference, but I fail to notice any "masked detail" appearing after EQ. But then again, I'm not familiar with the track and probably didn't know what exactly to listen for.

 

[MarkF786]

I'd echo the comments on light bass on the FDX1. I haven't done any A/B comparisons with other IEMs yet, but when listening to tracks I know well, it's hard to hear the bass guitar when at a moderate volume. The IEMs I listen to the most are Solaris, EX1000, Z1R, and SE846 - two with relatively flat bass and two with boosted bass. The FDX1 sounds leaner then them all (based on memory though). I'm using the most damped filter, along with Symbio Peels eartips.

I do wonder if it's because I'm adjusting the volume based on frequency peak, therefore making the bass truly less in volume.

Also, I wonder if the heavy, all metal construction of the FDX1 is playing psychological tricks on me, making me expect the sound to be bright and brittle (which has been my initial impression), though it's been improving either due to burn-in, my ears acclimating, or the psychological bias wearing away.

After a few days of intermittent listening (and about 36 hours of burn-in), I'm not yet a fan of their sounds, though again they seem to be improving. I'll report back after doing more direct comparisons with other IEMs.

 

[james444]

I'm using the most damped filter, along with Symbio Peels eartips.

Is it the same for you with stock tips? Just asking, because I can't get the same 100% kind of seal with my Symbio tips as with the softer Spiral Dot+ tips.

 

[Nabillion_786]

I already have Kanas pro, tanchjim oxygen and ath ckr 100 which all are outstanding dd iems but still not exactly what I'm after that's why I was hoping these jvc's would be the solution after some favourable reviews. It seems as though these could be a downgrade over them as many here aren't really sounding like there in love with the sound. All I need is a stellar midrange with clarity and a spacious stage. Hoping people would touch in on these aspects.

 

[MarkF786]

Is it the same for you with stock tips? Just asking, because I can't get the same 100% kind of seal with my Symbio tips as with the softer Spiral Dot+ tips.

I'm not able to get a good seal with the stock Spiral Dots+ tips due to the thinner material - though normal Spiral Dots work. I've also used some other tips with the FDX1 that worked well, like SpinFit CP100, Auvio (I bought a bunch of these on clearance), Symbio, etc. My ears tend to be pretty forgiving with a variety of eartip brands, if appropriately sized (usually medium).

I did do direct some comparisons tonight with the EX1000, and the bass levels were similar, with maybe more sub bass in the FDX1 - so the prior perceived bass difference must be more psychological, or caused by me adjusting the volume lower with the FDX1.

One thing I did notice, when listening to a track with obscene bass ("Slow Down the Bass", a song of little musical value, but good for testing how "well behaved" a headphone is with bass) is that when the bass is pushed hard on the FDX1, it's unable to simultaneously play higher frequencies at equal levels; in this particular track, the higher frequency percussion is drowned out by the bass - but even some TOTL IEMs suffer from the same problem (like the Z1R).

 

[morndewey]

The definitive answer is to simply look at your set of nozzles. You should see a clear difference in amount of damping material.

Great photo. You reckon that damping material is secure in there or more like nestled tissue paper?

 

[morndewey]

Reading impressions (and ensuing debates) I can’t help but marvel at the sheer subjectivity of it all. The graphs appear to relate objective data but, even then, there’s room for disparate results depending on set up variables. Even accepting the data as objective, the gap between input (auditory freqs) and output (perceived sound) remains enormous. Which is why it doesn’t make too much sense to make sweeping judgments one way or the other. Just thinking out loud

 

[rkw]

You reckon that damping material is secure in there or more like nestled tissue paper?

Probing with a needle, it doesn't move and isn't sitting completely loose as with the original @james444 mod.

 

[morndewey]

Probing with a needle, it doesn't move and isn't sitting completely loose as with the original @james444 mod.

You are a brave soul. Excellent work! Beware: Intrepid folks haunt these environs. Crimony! Mama always told me keep your finger from the socket!!!

 

[surfgeorge]

Reading impressions (and ensuing debates) I can’t help but marvel at the sheer subjectivity of it all. The graphs appear to relate objective data but, even then, there’s room for disparate results depending on set up variables. Even accepting the data as objective, the gap between input (auditory freqs) and output (perceived sound) remains enormous. Which is why it doesn’t make too much sense to make sweeping judgments one way or the other. Just thinking out loud

I wanted to write something like this but you put it in much better words than I ever could have.

I wrote quite a bit about the FD02 (which again is virtually identical to the FDX1, but I used a different mod) on the Moondrop thread and the FD01 thread.
Post #1598
Post #2274
Post #188 and following (warning: honeymoon period )

 

[jsmiller58]

Discovered today just how tip and stem position sensitive these IEMs are for me. I really could not get the included Spiral Dots to give me a good seal. Went to my usual standby, Symbio peels. A bit better seal, but still only so so, lots of ambient sound leakage, cold trebly sound sig, anemic bass.

Tried Sedna tips... also rotated the tips away from me (previously they were rotated towards me... What a difference! The JVCs warmed right up and have a much more impactful bass. I will try the Spiral Dots and Symbios with the stem rotated away so that I can determine if either the tips or the position of the stem make the bigger difference.

With these changes the JVCs went from “sigh, not another wasted purchase” to “hmmm... I want to get to know these a lot better!”

Are they bass cannons? No, and they are not trying to be, they seem to want to deliver a balanced representation of music. But, they have impactful bass where bass is present in music!