Hiby FC6 - another R-2R USB dongle
Mar 9, 2023 at 4:22 PM Post #92 of 417
Plenty of power for my IEMs, loud, clear, and dynamic with good bass body, impact, and rumble on Ara and Andromeda 2020. I don't have any full size headphones, but hopefully somebody can comment on that here soon.

Can't wait for your comparison with DC03PRO, that little gem is a real cracker 😀 it has some warmth to it too.
 
Mar 9, 2023 at 10:07 PM Post #93 of 417
Measured FC6 (oversampling, 32 ohm load via E1DA Cosmos using RMAA). Result are mostly decent for a R-2R DAC and definitely not as good as a ToTL D-S dongle (i.e. L&P W2), which is as expected. The only part that I really don't like is roll-off. As you can see below, there is a HUGE roll-off at the top end (-3dB @ 15kHz~18kHz) which is just way too much. The roll-off at the bottom is also weird, but forgivable for being fairly minor.

FC6 Filters Spectrum.png


Here is NOS vs. OS under Slow Normal filter setting. NOS measured a few dB worst than OS, which is completely normal. Top end gets slightly extended under NOS as it technically should disable the digital filter (and therefore allow more frequency as well as noise to passthrough). Still, the roll-off is too much.

FC6 NOS Spectrum.png


True shame.
 
Last edited:
Mar 9, 2023 at 11:27 PM Post #94 of 417
That looks weird, especially since you described it as cleaner sounding than ru6. I would think it would sound warmer than ru6 with the drop off. Oh well I'll give a listen soon. I can compare with the dco3 pro which is one of my favorite dongles. Of course it's DS and towards neutral, with a bit of boost on both ends and laid back mids.

Maybe Joe Bloggs can comment on that drop. I thought it was usually 20 to 20 + - .05 db. Oh wait specs show 20hz to 40khz - 3 db?

Should be polar opposites, the dco3 and fc6.
 
Last edited:
Mar 10, 2023 at 2:11 AM Post #95 of 417
Here is a comparison on how RU6 responded on NOS vs OS

RU6 Spectrum.png


If I remember correctly, the original ideal of NOS is to have no digital filter at all and then use the human natural hearing limitation to 'filter' out the high freq. noise caused by the sampling process. But the more popular implementation is to has a steep Butterworth filter with NOS to smooth out the noise, which is basically what is implemented on RU6 - Normal digital filters with flat FR curve when oversampling and steep roll-off Butterworth filter when NOS. With FC6 however, it would seems it is stuck permanently with a Butterworth filter regardless whether on NOS or OS (while NOS disable the other extra digital filters?).

That looks weird, especially since you described it as cleaner sounding than ru6....

I usually have my RU6 on NOS and didn't switch to OS when comparing it to FC6. There are also other factors that affect how I perceive cleanness, such as the thickness of the mid-range and the overall width / compression / resolution of the image.

I am hoping this is just another firmware glitch as it would seem kinda pointless to give the filters and NOS/OS option to user when you essential has more of less the same roll-off.
 
Last edited:
Mar 10, 2023 at 6:01 AM Post #96 of 417
Measured FC6 (oversampling, 32 ohm load via E1DA Cosmos using RMAA). Result are mostly decent for a R-2R DAC and definitely not as good as a ToTL D-S dongle (i.e. L&P W2), which is as expected. The only part that I really don't like is roll-off. As you can see below, there is a HUGE roll-off at the top end (-3dB @ 15kHz~18kHz) which is just way too much. The roll-off at the bottom is also weird, but forgivable for being fairly minor.

FC6 Filters Spectrum.png

Here is NOS vs. OS under Slow Normal filter setting. NOS measured a few dB worst than OS, which is completely normal. Top end gets slightly extended under NOS as it technically should disable the digital filter (and therefore allow more frequency as well as noise to passthrough). Still, the roll-off is too much.

FC6 NOS Spectrum.png

True shame.
Depends on how it sounds.
 
Mar 10, 2023 at 6:11 AM Post #97 of 417
Depends on how it sounds.
Of course that's the most important point (and my previous opinion on how it sounds still stands). But on occasion, I'll also like my gear lives up to its published spec. That's why measurement has its place. It gives the other side of the story that sometimes human's hearing just can't tell easily.
 
Last edited:
Mar 10, 2023 at 6:01 PM Post #98 of 417
Got it today, first impressions are very good. Build and screen are nice, easy to use and of course works nice with hiby app.

Sound so far, very nice, Rich, liquid like, timbre is excellent and dynamics very powerful. Sounds similar to cayin ru6 except as ClieOS said- well I'll put it into my own words it seems more open/spacious and a bit sharper/more defined. But with weight and density of analog sound. This is using NOS with fast filter.

It does kind of have a bit of both DS and r2r traits which is nice imo. Cons so far- well I don't like the OS mode, it kills some energy to me and the disconnect pop which others have mentioned. I'll post some pics later and talk about power drain. It's just a bit bigger than dc03 pro which is pretty small. And I like green anyways. The little case is very nice too.

Compared to dc03 pro, well it sounds a bit dull after listening to the fc6 there's a rawness and power and purity that fc6 has. However there's a huge price difference and as DS dongles go, I don't think you can do better for the price.

Oh bass has nice punch and isn't a bit flabby sounding. Mids are open and 'wet' organic and treble is precise and sounds just right on percussion instruments. It's not a shy treble either and I personally don't notice a rolloff, but my hearing.... Well I'm older so you know 😏 No 4.4 (which personally doesn't bother me) and the price 😞 the cayin is a better value but I'm digging the sound and who knows, the price might drop. Or a sale. Personally like the smaller size and the screen is nice.

These analog sounding devices take me back to walkman days. When cassettes ruled and we had Sony 'mega' bass. Ha ha.

Ok, couple of pics

20230310_180739.jpg
20230310_180751.jpg
20230310_180910.jpg
20230310_180946.jpg
20230310_181325.jpg
 
Last edited:
Mar 11, 2023 at 1:33 AM Post #99 of 417
Got it today, first impressions are very good. Build and screen are nice, easy to use and of course works nice with hiby app.

Sound so far, very nice, Rich, liquid like, timbre is excellent and dynamics very powerful. Sounds similar to cayin ru6 except as ClieOS said- well I'll put it into my own words it seems more open/spacious and a bit sharper/more defined. But with weight and density of analog sound. This is using NOS with fast filter.

It does kind of have a bit of both DS and r2r traits which is nice imo. Cons so far- well I don't like the OS mode, it kills some energy to me and the disconnect pop which others have mentioned. I'll post some pics later and talk about power drain. It's just a bit bigger than dc03 pro which is pretty small. And I like green anyways. The little case is very nice too.

Compared to dc03 pro, well it sounds a bit dull after listening to the fc6 there's a rawness and power and purity that fc6 has. However there's a huge price difference and as DS dongles go, I don't think you can do better for the price.

Oh bass has nice punch and isn't a bit flabby sounding. Mids are open and 'wet' organic and treble is precise and sounds just right on percussion instruments. It's not a shy treble either and I personally don't notice a rolloff, but my hearing.... Well I'm older so you know 😏 No 4.4 (which personally doesn't bother me) and the price 😞 the cayin is a better value but I'm digging the sound and who knows, the price might drop. Or a sale. Personally like the smaller size and the screen is nice.

These analog sounding devices take me back to walkman days. When cassettes ruled and we had Sony 'mega' bass. Ha ha.

Ok, couple of pics

20230310_180739.jpg20230310_180751.jpg20230310_180910.jpg20230310_180946.jpg20230310_181325.jpg

Appreciate the first impressions; good reminder that actual listening is most important.

Have you gotten a chance to try the FC6 with an external amp?
 
Mar 11, 2023 at 4:27 AM Post #100 of 417
Measured FC6 (oversampling, 32 ohm load via E1DA Cosmos using RMAA). Result are mostly decent for a R-2R DAC and definitely not as good as a ToTL D-S dongle (i.e. L&P W2), which is as expected. The only part that I really don't like is roll-off. As you can see below, there is a HUGE roll-off at the top end (-3dB @ 15kHz~18kHz) which is just way too much. The roll-off at the bottom is also weird, but forgivable for being fairly minor.

FC6 Filters Spectrum.png

Here is NOS vs. OS under Slow Normal filter setting. NOS measured a few dB worst than OS, which is completely normal. Top end gets slightly extended under NOS as it technically should disable the digital filter (and therefore allow more frequency as well as noise to passthrough). Still, the roll-off is too much.

FC6 NOS Spectrum.png

True shame.
As you have said earlier in this thread though, R2R dacs generally do not measure well when compared to DS dacs. The Cayin RU6 has taught me that measurements are a very small slice of the overall 'listening experience' pie. It's not worth digging deep into the measurements because of this.

I have many DS dacs that measure really well. However, I wouldn't argue that they are better than RU6. They are certainly not as musical and organic sounding as the RU6 - so who necessarily cares about the measurements? You're not going to find the best 'sounding' dac from measurements alone. The RU6 is an amazing dongle that has enough juice to power difficult to drive cans, despite the fact it was designed mainly for IEMs.
Where the measurements are interesting is when compared directly (FC6 v RU6).
 
Last edited:
Mar 11, 2023 at 4:34 AM Post #101 of 417
Got it today, first impressions are very good. Build and screen are nice, easy to use and of course works nice with hiby app.

Sound so far, very nice, Rich, liquid like, timbre is excellent and dynamics very powerful. Sounds similar to cayin ru6 except as ClieOS said- well I'll put it into my own words it seems more open/spacious and a bit sharper/more defined. But with weight and density of analog sound. This is using NOS with fast filter.

It does kind of have a bit of both DS and r2r traits which is nice imo. Cons so far- well I don't like the OS mode, it kills some energy to me and the disconnect pop which others have mentioned. I'll post some pics later and talk about power drain. It's just a bit bigger than dc03 pro which is pretty small. And I like green anyways. The little case is very nice too.

Compared to dc03 pro, well it sounds a bit dull after listening to the fc6 there's a rawness and power and purity that fc6 has. However there's a huge price difference and as DS dongles go, I don't think you can do better for the price.

Oh bass has nice punch and isn't a bit flabby sounding. Mids are open and 'wet' organic and treble is precise and sounds just right on percussion instruments. It's not a shy treble either and I personally don't notice a rolloff, but my hearing.... Well I'm older so you know 😏 No 4.4 (which personally doesn't bother me) and the price 😞 the cayin is a better value but I'm digging the sound and who knows, the price might drop. Or a sale. Personally like the smaller size and the screen is nice.

These analog sounding devices take me back to walkman days. When cassettes ruled and we had Sony 'mega' bass. Ha ha.

Ok, couple of pics

These are really good images. It is a very luxurious looking dongle. Not sure whether you require both the wallet case and leather sleeve though. Cayin could maybe have missed out the wallet case and knocked the proce down 20 bucks or so. What do you guys think?
 
Mar 11, 2023 at 5:42 AM Post #102 of 417
Yes they could have scrapped the leather box and charged a bit less. Although It might not be real leather and not cost hardly anything to produce.
 
Mar 11, 2023 at 5:53 AM Post #103 of 417
.... It's not worth digging deep into the measurements because of this....
I am not specifically looking for the best measuring USB dongle (*well, I already own W2 and W2-131, and they both sound and measured great, if not the best among all the USB dongle in the market). I am more interested in different implementation.

That being said - measurement is not what I used to judge how good an USB dongle sounds to my ears, but to detect possible issues that might be hard to tell by ears alone. For example, I am getting older so my upper end hearing isn't nearly as good as it used to be when I started this hobby some 20+ years ago. It will probably be perfectly fine to me personally if I keep the roll-off issue a secret as it doesn't affect me as much as it would have been 20 years ago when I can hear treble much better than I am now. But if I were to share my opinion regarding FC6 to a 20 yrs old person, then obviously my opinion will be somewhat misleading. In that case, it is better to know all the fact then just one person's opinion in order to make a more informed decision. Now you might think a 3dB roll-off might not be that big of a deal, but I have come across gears that unknowingly change the FR curve of the headphone, gears that have unacceptable high distortion (high enough that I can tell by ears, in the 10% range), and gears that have only a single digit mW output power but claimed to have much much more - these are all gears that were highly praised by some members in the forum at one point or another before measurements were published. Again, not saying measurement is the be-all-ends-all, but it has its usefulness to the user when used constructively to understand that our hearing has its limitation. If a gear is well-designed and engineered, then it shouldn't be a problem at all.
 
Last edited:
Mar 11, 2023 at 6:55 AM Post #104 of 417
The thing with measurements goes both ways. I've owned some gear that measured really good that I found the sound well just meh, not my cup of tea.

And stuff that didn't measure so well like sonys sounding very good to my ears. I'm sure the dc03 pro measures with the best of dongles, the specs are really high. But comparing it to the fc6 it just sounds more defined, more open, more natural and better all the way up and down from bass to treble. How it sounds to me, my ears is all that matters. Really listening with your own gear with your own ears is the only way to know if something sounds good or not. Probably because there's so many variables that a line or graph can't convey, plus personal preferences, ear shape, bias- well hopefully not bias but were all human. 😉

I think measurements are invaluable in a lot of circumstances, like power output, linearity etc. And obviously in diagnosing problems. When it comes to sound quality/enjoyment though I trust my ears and take measurements with a grain of salt. That's the best advice I can give, your own ears are the best tools for gaging audio quality.

Now, having said all that, I 100% agree with clieOS with the fact that the OS and NOS filters are so close. I can hear a difference but I would expect the OS filter to not follow the same curve as the nos. Maybe this will be changed in firmware because me personally, I don't think OS mode sounds good. I'm assuming there will be firmware down the road.
 
Last edited:

Users who are viewing this thread

  • Back
    Top