FLC Technology FLC8 and FLC8s Impressions Thread
Nov 29, 2020 at 9:14 PM Post #7,831 of 7,931
Are there any wireless earphones that rival these? I've had them I think for 4 years, but my lg v20 got stuck at the boot screen, so I got to join the headphone jack-less era. Or maybe I'll get a DAC adapter.
If you are an Android person the higher end Samsungs get good reviews. If you are an Apple person the Airpod Pros are very nice.
None of these can touch the FLC8S however. But its a different use case.
 
Nov 30, 2020 at 10:25 AM Post #7,833 of 7,931
Could need an advice if I should go for the FLC8S Blue Braided Cable or the FLC8 Black TPU Rubber Cable offering by lendmeurears, since I need a replacement.
If I recall the black ones don't have the memory cables. Some people don't like the memory jackets so that might be an advantage. I have the blue style cables on my FLC8D (different cable of course) and they fit just fine for me.
 
Dec 25, 2020 at 4:46 AM Post #7,837 of 7,931
Apr 1, 2021 at 7:12 AM Post #7,839 of 7,931
Look at the reviews from Brooko and HiFiChris for more graphs with different filter configurations: https://www.head-fi.org/showcase/flc-technology-flc-8s.21068/reviews

What's confusing me tho is that in csglinux' graph, the curve goes up after 2kHz, while the curve only goes down after 2kHz in both Brooko's and HiFiChris' graphs:

XwIzZBI.png

Colored = Brooko
Grey = HiFiChris
White = csglinux

Why is csglinux' graph that much different while the other two are at least somewhat similar? (sorry if it's a stupid question, I'm new to this)

Not a stupid question at all. There can be a lot of subtleties to this. Generally, you don't ever want to compare results from two different rigs, because there are a whole host of things that could legitimately be different, including:

1) Different types of eartips
2) Insertion depth
3) Unit variation between headphones
4) Coupler transfer impedance
5) Coupler microphone

We know 1) and 2) play a large role in the treble. @Brooko and @HiFiChris are probably not using the Cp100 eartips I'm using. I think Cp100 are more comfortable and sound better (to me) than the stock FLC tips, but I'm not judging. Others have to decide for themselves, because different eartips and insertion depths will give different results for different people. 3), 4) and 5) could cause discrepancies anywhere over the frequency spectrum. To give an indication of 3), look at the variation in the left and right channels of my FLC8s and FLC8d using gunmetal filters:

flc8s_gunmetal.png
flc8d_gunmetal.png
(Note that the previous results I showed were averaged over the L and R channels.)

BTW, somebody else had asked to see results with the gold HF filters. Here they are:

flc8s_gold.png
flc8d_gold.png
And an L/R averaged comparison of the two headphones, both using gold HF filters:
gold.png

You can see that the channel balance on my FLC8s and FLC8d is fair but not perfect. We have to expect some variation from unit to unit.

As for item 4), I believe both @Brooko and @HiFiChris are using what's called a Vibro Veritas coupler. I have one of those too, and they're perfectly fine - but they will give a different response to that of a 711 coupler. (My measurements were using a GRAS RA0045 coupler). Compensation files can help, but you can't expect a perfect match between Vibro Veritas and 711 measurements when hopping back and forth between sealed and ported IEMs.

In my experience, the biggest discrepancies usually come from 5), i.e., the coupler mic, and in my experience, the Vibro Veritas mic is its Achilles heel. It's not particularly flat, even just from 20 Hz -> 10 kHz. Having said that, if you're wanting to know which of these measurements is correct, there's an easy answer to that: none of them. None of them will exactly match the response from your own ear canal. But that doesn't mean these measurements aren't useful. What we're looking for is the trend and any rig (711 or Vibro Veritas) will be able to show you the effect of switching from gunmetal to gold HF filters, or from switching from FLC8s to FLC8d, etc.

As for trying to get individual rigs situated on the other side of the world to compare with one another... actually, we're working on that too :) We have a little touring IEM project which anybody (@Brooko? @HiFiChris?) is welcome to join:

https://www.head-fi.org/threads/ety...phone-for-your-ears-and-your-couplers.908512/

Thank you for explaining @csglinux! Your graph does seem to make much more sense to me because I get the sibilance/harsh treble right around that 3.5kHz area where only your graph shows a peak but it's still crazy to me that the discrepancies could be so huge even with all those factors you mentioned.

I guess this all just means that any single frequency response graph is completely useless unless you use it in the context of direct comparison to another measurement done on the same rig.
Which really sucks because on my search for the right IEM for me it would be so useful to have definite/consistent measurements of all the IEMs I have owned/heard before so I could eventually determine the sort of frequency response curve I prefer and look at IEMs based on that. I thought that's probably how it goes, but perhaps not.

In theory, a 711 coupler ought to get closer to what you'd hear than a 3D-printed cylindrical plastic tube (which is basically what the Vibro Veritas coupler is). I'd be happy to drill down on this some more if @Brooko or @HiFiChris are willing to share their Veritas compensation curves with me.

But, yes, your conclusion is sadly correct. There are just too many variables. 711 couplers are supposed to be good (i.e., have a defined tolerance on transfer impedance) up to 10 kHz, but in practice that's only for deep insertion IEMs. The effects of different eartips and insertion depths can be very significant. Shallow insertion can easily cause the half-wave resonance peak to drop below 10 kHz.

Are you aware of @crinacle's database? It's not exhaustive, but all his measurements were made on a 711 coupler, and more importantly, they were all made on the same 711 coupler: https://crinacle.com/graphs/graphtool/

It's indeed true that Paul and myself have taken the measurements on the Vibro Veritas coupler (quite crap thing but at least better than nothing at all - wouldn't have bought it if I had known that the claims that were made prior to its release wouldn't be delivered in the end (e.g. accurate-enough IEC711 compensation), and that the (small, but still...) pre-order discount wouldn't be filled in on the customs form wherefore I ended up paying more import duties than I should...).

It's worth to notice that (uncalibrated) unit to unit variance on these Vibro Veritas couplers can be quite huge - while I'm more or less lucky and get a fairly accurate result in the range between 20 Hz and 1 kHz without any further calibration file, I know other people whose Veritas mic is a total outlier and has got a very strong roll-off in the lows and lower mids.
Aside from that, my measurements have a pseudo-IEC71-diffuse-field-target-compensation-compensation applied to them (but in the tens (!!!) of hours I spent on trying to calibrate this thing, I didn't manage to get close enough in the range between 2 kHz and 7 kHz and this area therefore shows too little level; it's fine to me and I can adjust the graphs in my mind as I am familiar with them, but others who are not used to these graphs will obviously not interpret them correctly without any overlays of other well-known IEMs), whereas Paul's are pseudo-raw-IEC711-compensated, so his are closer to raw IEC711 measurements whereas mine are, except for the range between 2 kHz and 7 kHz that I didn't bother to spend tens of other hours on to get a closer match, closer to diffuse-field-target compensated IEC711 measurements.
Anyway, that's also the reason why instead of posting those crappy graphs, overlays and compensations, I switched over to publishing my measurements compensated with the frequency response of my Etymotic ER-4S and InEar ProPhile 8, and those ER-4S- and PP8-compensated measurements are a much closer match (all in the range of still small differences on some measurements due to different insertion depths with some IEMs as not all can be inserted deep enough into the Veritas coupler) to measurements on a real IEC711 coupler with applied ER-4S-compensation, at least when I compare them to the graphs on the graph tools on Crin's and banbeau's websited with applied ER-4S compensation.

In addition to that, my FLC8s do probably, as mentioned, vary somewhat more from some other FLC8s units, as mine are definitely closer to Ety-neutral with the grey ULF filters as opposed to the clear ULF filters which create a less-than-neutral bass output. And I'm using the included silicone tips.
 
Apr 10, 2021 at 12:51 PM Post #7,841 of 7,931
Still in love with the 8S, yeah they looking more like a chinese gadget but sounds excellent.

I guess FLC is done for now unfortunately, Flcforrestwei posted here somewhere that newer models did'nt sold well.
Last summer they offered their flagship Celeste for half of the price on chinese market.
 
Apr 11, 2021 at 12:45 AM Post #7,842 of 7,931
Still in love with the 8S, yeah they looking more like a chinese gadget but sounds excellent.

I guess FLC is done for now unfortunately, Flcforrestwei posted here somewhere that newer models did'nt sold well.
Last summer they offered their flagship Celeste for half of the price on chinese market.

Does anybody know if there are any frequency response measurements of the Celeste publically available anywhere on the internet? Their concept was very interesting, but it seems like (just like Fidue) FLC changed their view and abandoned the international/Western market and shifted to Asia only.
 
Apr 11, 2021 at 10:53 AM Post #7,843 of 7,931
Still in love with the 8S, yeah they looking more like a chinese gadget but sounds excellent.

I guess FLC is done for now unfortunately, Flcforrestwei posted here somewhere that newer models did'nt sold well.
Last summer they offered their flagship Celeste for half of the price on chinese market.

That is super sad that FLC is not doing so well. I think people say that they want a tunable unit but I think most only want a small level of tuning at the end of the day. Easily screwed in filters is what the market wants and FLC went too far for most people with tuning options. I know that I found a low end tuning on the 8S that I liked which was baked into the 8D. I got tired of losing pieces so went for the 8D. But must say that the revised version of the 8S had much better tolerances and I lost almost no pieces. LMUE took back my first pair under warranty which was great service.

I don't think anybody properly reviewed the 8D which was a shame because they are very good. But they fell under the shadow of the 8S / 8N. I think the 8D has a slightly better low end sound signature than the 8N because it is not tunable in the bass. In other words there aee no losses in that region. due to tuning pegs.
 
Apr 13, 2021 at 3:25 AM Post #7,845 of 7,931
None idea if you'll find any frequency response measurements online, while you can use google translate to translate these chinese webside into your native language

http://www.soomal.com/doc/10100007951.htm

Thanks. At least some more photos of the Celeste.

Unfortunately one has to be registered there in order to read the sound analysis on page 2 (which I just did - just need to wait for my Soomal account to be activated).
 

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