For those asking for a comparison, Z1R has more bass. FW10K's only measurement out there seems to imply a rather large bass boost, but in reality the FW10k is very much vented to a large extent. Isolation really isn't that great. Bass levels can even feel anemic at times. FW10K also has a huge uppermidrage spike. I compared them to the RHA CL2. Everyone knows how much uppermids the CL2 have.
In practice, CL2 sounds better than FW10K since FW10K is just harsh next to them. Lower mids on the JVC are thin, brittle and too recessed. Whereas CL2's lower mids don't sound anywhere that bad. Imagine a greater upper midrange presence than CL2 WITH plenty more lower treble. That's what the JVC sounds like.
I don't like the CL2 but CL2 has its strengths with certain types of music. The FW10K? Just sounds terrible no matter what I play with it. And no, this is not a seal or fit issue. I think they just sound flat out terrible.
Z1R has a stronger bass response (which to some borders on way too much bass; it's perfectly fine for me), better balanced midrange with the uppermids taking slight precedence, and a very much present but unobstrusive treble. Z1R extends better on both ends. I personally do feel the Z1R is several leagues ahead and is more versatile. You have to have very specific genre and sound preferences to enjoy the JVC.
I have both the 1r and 10k. To make it short, did an A/B/C (subject being 1r, 10k and a Japanese brand called Ar:tio RK01) blind test with
1. different tips (foams, silicon and smp etc) 2. different dap/amp tube/suax01/cayin N8/sp1000), 3. different cables (stock mod 4.4 pentaconn, others see sig), 4. different people (4 including myself) with different ear canal and size, 5. different gender and age group (1F3M ranging from 25+ to 40+), 6. music genre: Jpop, R&B, rock, concert, Jazz, classical, therapy track, pure vocal male and female, one of each)
Blind tested without knowing the price or tech behind each pair. Environment: ambient dB lvl @ approx. 50-60db.
Conclusion? Majority picked 10k with a grin on their face and a “wow” on 1st impression, rk01 being second and 1r being the least interested due to them sounding like another pair of ordinary earphones = boring. Must give credit to 1r with its jewelry look. They immediately caught our lady tester’s attention when opened up. She was most interested in 1r at first but turns out disliking them with the fit, size and sound.
We took a 2nd and 3rd test impression with different pairing to even out the bias that might have during 1st listening.
When prices were finally unveiled, the only chosen one was 10k and rk01, where 1r was the least desired.
10k being the most desired for sounding and fitting (con: with the impression of fatigue after long hours of listening due to the sound sig.), RK01 being the best choice out of the 3 to be used daily for extended hours, easily best in terms of cost to performance. 1r ...well, it’s a waste of time and hard earned bucks.
That test eventually seals the fate of my pair of 1r and they are up for sale. For me it is definitely a hard lesson learned.
However like some says, “different people has different ears and hearing”, best to try them out yourself, like I did... ;P
(rk01: 200usd 10k: 1700usd, 1r: 1800usd)