[DanTra]

The blues are 554, blacks are 556

I see. Thanks!

 

[ian91]

Over a month now with both the U-554 and the U-556. Both are shining examples of a well executed IEM. I prefer the U-554 that casts a slightly wider and brighter image than the U-556, that itself leans taller in stage height and more intimate in imaging and stage width. The U-554 has an equisite tonal balance with excellent detail retrieval. It is at once analytical and musical. You can pause to be critical and dissect elements of a track or simply enjoy the greater whole. With my music library (ambient, instrumental, vocal) I have only on occasion reached for the U-556. As I mentioned previously the U-556 certainly sounds more 'natural' and might have the edge with percussion and bass instruments...but having said that, the U-554 offers me enough bass with good extension to replay all instruments with reasonably good accuracy and has slightly more control down low than the U-556.

To support the excellent tonality both sets have great imaging and soundstage with prominent layering that retains coherency during busy passages. *chefs kiss*

Some observations to help inform any potential buyers:

• U-554 for acoustic / jazz / instrumental music is a no-brainer. However, the uppermids tow a fine line offering excellent presence, detail and texture but as a consequence can become shouty on the odd poorly recorded track.
• For this reason it is even more important to ensure the U-554 has an appropriately deep fit to ward off any uppermid/treble resonance from the ear canal that can add to this effect.
• U-556 has less overall resolution and differs in technicalities with a noticeably warmer and less energetic presentation that makes less refined recordings more palatable. This would be my place to start if you're unfamiliar with this tuning or uncertain how deep your fit will be.
• If you're coming from any other tuning than DF there will be an adjustment period. The BA presentation and the neutral tuning is a refreshing experience. For myself it has almost been a detox from overly extravagant boosts in other sets in regions that simply don't need it. Note weight will be lighter if you're coming from a DD but give it some time.
• Have a selection of appropriate tips to hand to improve the chances of a deep fit. You will know you've gone deep enough when your own vocal resonance becomes much quieter. If you're new to this type of fit, take your time and make it a gradual process over days with short listening periods, your canal should slowly become more accomodating.

My favourite source pairing is with the RU6, high gain, NOS. Paired with the R2R config in the RU6 they put on an incredibly organic and textured show and despite my earlier judgement the RU6 drives these perfectly well. The synergy here is undeniable. The Shanling M8 after much listening time smoothens too much of the natural texture that these little BAs are able to put out and warms things from a tonal perspective.

I've been more content this past month than I have at any point since entering this hobby. Despite this, a part of me is dreaming what Yu9 might be capable of doing in the future...maybe a multi-BA with a similar execution and design philosophy? Would adding more drivers really add anything substanstial? I'm really not sure. For now I'll just enjoy these.

 

[counterclockwise]

look who made it out of Shanghai eventually ^_____^

(can now confirm that the huo niu store on aliexpress ships from an address in Shanghai)

 

[ian91]

look who made it out of Shanghai eventually ^_____^



(can now confirm that the huo niu store on aliexpress ships from an address in Shanghai)

Wahey! Welcome to the club. Your sapphires are looking good!

 

[RockaRolla]

How do they compare against the Ety ER2/3, JVC FDX1 and 7hz Timeless??

The shell designs of these are really nice!

 

[counterclockwise]

Had a few hours with the u554 now. Some impressions.

- Overall they sound pretty excellent. Precise, neutral, transparent. The diffuse field tuning has a certain openness and directness that I always miss in coloured transducers. If I understood correctly, Yu9's goal in developing the u554 was to make a DF-tuned iem with a "natural" sound, and I think they did a great job at that. I plug these in and they just sound right without any EQ wrestling. Lovely.

- Going back and forth between the u554 and er4sr (grossly unfair comparison in terms of price of course), the u554 seems somewhat more energetic in the high treble range, making them airier and more aggressive in comparison. My fit being less than ideal could be affecting the treble response, but I could also see it being part of a strategy for creating a more spatial sound. Ian noted that the u554 has softer attack and decay than (Yu9's) er4b, and unsurprisingly the same holds in comparison to the (Ety) er4sr. In terms of the effect on presentation I'd describe the u554's sound as somewhat glossy and the er4sr's as more matte. I'm not gonna get into quantifying soundstages, but the softer decay does give the u554 a more spatial sound, while it loses to the er4sr on fine texture.

- Pretty charmed with the peculiar design on these. Kinda utilitarian but with a lot of character. Noticed that if you look closely at the shells or run your fingers over them, there are subtle variations in the curvature, as you'd get from molding a shape by hand. Guessing these weren't designed as CAD models. Kinda neat.

- Fit is iffy at best for me. I have no problems with the er4sr but I'm struggling a bit with these, and I'm not quite sure why. The combination of deep fit and over-ear wire may be making a bit too many assumptions about the wearer's ear anatomy. Getting my best fit so far with the semi-translucent dual flanges (which seem to be triple flanges with the top flange cut off, upon close inspection?).

- The case is adorable. those fishes. ^______^

 

[ian91]

the u554 seems somewhat more energetic in the high treble range, making them airier and more aggressive in comparison. My fit being less than ideal could be affecting the treble response, but I could also see it being part of a strategy for creating a more spatial sound.

This was my initial impression of the treble, until one evening when I gave Ety dual flange (softer silicone) a go and managed to achieve greater insertion depth and seal, then that treble aggressiveness was tamed and a better degree of clarity emerged.

I would definitely recommend continuing to experiment with fit and tips as able. I hope you find something that works.

Ian noted that the u554 has softer attack and decay than (Yu9's) er4b, and unsurprisingly the same holds in comparison to the (Ety) er4sr.

A part of me wonders if this is down to the Sonion vs Knowles/custom Ety BA. I have always found in other IEMs that Sonion BA have a smoother approach to things. This is often at the expense of resolution but I thoroughly enjoy the more organic Sonion sound. Maybe I'm just imagining the difference - who knows.

The combination of deep fit and over-ear wire may be making a bit too many assumptions about the wearer's ear anatomy.

I think you're possibly right here. I had more issues with their 4b model with the traditional stick shape interestingly...

Getting my best fit so far with the semi-translucent dual flanges (which seem to be triple flanges with the top flange cut off, upon close inspection?).

Yeah I think they took some scissors to them. What other tips have you tried?

 

[DanTra]

Anyone have these compared to the ER2XR? I'm choosing either ER2, the U-554 or the U-556. Do the YU9 models have the "BA Timbre"? Which sounds more "natural"?

 

[ian91]

Anyone have these compared to the ER2XR? I'm choosing either ER2, the U-554 or the U-556. Do the YU9 models have the "BA Timbre"? Which sounds more "natural"?

BA timbre is tough to discern and hard to define on paper. I do not hear either the 554 or 556 as having off-timbre effects. The 554 by virtue of its tuning, and maybe driver difference, leans brighter and tighter than the 556, but both reproduce instrument timbre authentically. I prefer the 556 for percussion because of the greater body but the 554 for vocals and strings due to the added midrange presence and treble air.

'Metallic' or 'plastic', words typically used to describe BA timbre, are not words I would use to describe either models. They are transparent and detailed, the 554 being supranormal in its clarity but still quite natural. The 556 is more 'neutral' to my ear and arguably more 'natural'. Note weight is greater and room acoustics feel more closed/dampened. I prefer the 554 for its open sound with greater high Hz presence.

I have not heard the ER2 line due to difficulty procuring one in the UK.

Let us know how you get on.

 

[hazael]

There's also no article on the U-554 though sadly.

The aliexpress store page has updated its description with the thought process behind the u-554. (It even links this thread, congrats!)

Probably Google translated as well.

"The design goal of the U-554 is to achieve accurate timbre and delicate details, and to present a reliable sound for serious listening situations. It can be understood that the U-554 has a stronger "work" temperament. This is different from the U-556's design goal of "natural mixing in the room", and the two models have their own emphasis and together form the Series 9 in-ear monitor series.

From the frequency response point of view, the 554 has more mid-high frequency energy than the 556, and the full-frequency energy distribution is very flat. Obviously, the 554 is not simulating the room effect, but trying to present the state of the undisturbed sound that reaches the ear. The 554 has a clear and solid image, delicate and elegant high-frequency detail, and clean and accurate mid-range tone.

The 554 also uses a unique acoustic rear cavity design. Under the fine tuning of the rear cavity technology, the 554 also has a loose and elastic low frequency response and extremely low distortion, which optimizes the sense of hearing.
In the 554's circular sound field, the sound information is scattered, as long as you pay attention, you will find the sound details are there, and when you withdraw your attention, these elements merge together again.

For sound workers, the powerful performance of the 554 is a powerful tool for you to examine the sound.
Sounds familiar, doesn't it, it's a lot like the kind of feeling the er4 series brings us.
It's a bit similar, but not exactly the same. The er4 series is our favorite, but in the workplace, we think that the details of the 4s are not enough, while the 4b is powerful but not natural. In addition, the people of the er4 series The sound is clear and calm, the low-frequency shape is precise but the elasticity and fullness are not enough, the high-frequency is easy to spike in some recordings, etc. ......

In the adjustment of the 554, we have polished the details of these aspects, balancing the relationship between performance and natural hearing. Incorporates our understanding of 'job reference' ."

I thought I was confident on the U-556 but now I'm not sure which one to get tbh especially already having the er2se. Cheers everyone, hope we keep getting more impressions.

 

[ian91]

I thought I was confident on the U-556 but now I'm not sure which one to get tbh especially already having the er2se. Cheers everyone, hope we keep getting more impressions.

A big part of me just wants to recommend the U-554. It might offer a different use-case than the U-556 that might overlap with the ER2SE. It just depends on how adventurous you're feeling and how far your tolerance extends for uppermid/lowertreble.

 

[ian91]

​

Sounding exquisite from the U-554 (+ RU6) this evening. Great imaging and layering, detailed instrumentals, sweet and spacious vocal work. So happy right now .

I would love to hear a challenger at $136 that manages this deft balance of tonality vs technicality. I'm aware of alot of DD offerings at this price point that are strong contenders but no single BA (apart from Ety ofc) and I do think BA offers something unique when implemented as well as Yu9 have here. You have speed, resolution, clarity and treble extension. DDs at this price point just can't match on these fronts I don't think (I would like to here the ER2 series though to compare).

 

[hazael]

A big part of me just wants to recommend the U-554. It might offer a different use-case than the U-556 that might overlap with the ER2SE. It just depends on how adventurous you're feeling and how far your tolerance extends for uppermid/lowertreble.

I do a lot of audio editing/recording/mixing with my etys so both offer different use cases in that area as well making it a bit tougher to choose from.

The U-556 because it's tuned to what well-tuned speakers sound like in a typical room which would help with realistic mix translation (something the er2se doesn't do well in my opinion) or the U-554 for the higher uppermid/lower treble detail with vocal editing.

I'm sure either would be a pleasure to listen to though, if I choose to purchase one I'll make sure to post an update in the future.

 

[counterclockwise]

Yeah I think they took some scissors to them. What other tips have you tried?

Everything in the box, for starters (got the set with the "Ety grade triple flanges" included). And original Ety triple flanges, and some softer third party triple flanges. The DIY double flanges still work best for me though, and after some breaking in and trial & error I'm getting a good stable fit that lasts for a couple of albums before getting uncomfortable now. yay. Properly addicted to these now.

This was my initial impression of the treble, until one evening when I gave Ety dual flange (softer silicone) a go and managed to achieve greater insertion depth and seal, then that treble aggressiveness was tamed and a better degree of clarity emerged.

Looking at the frequency response curves for both (with the caveat that we don't have measurements for both from the same measuring rig of course), the u554 does show a second hump above the pinna gain, peaking at about 9db above baseline around 13~14khz. The er4sr stays comparatively close to the baseline above the pinna gain region (i.e. from 7khz onward). Think that may explain the airier sound. Works well with the softer timbre really. Compared to the stoic precision of the er4sr it's certainly a sweeter and more enveloping presentation. Also a little more forgiving overall (although the slightly stronger upper treble seems to bring out clicking noises of badly cut samples even more than the er4sr does).

How do they compare against the Ety ER2/3, JVC FDX1 and 7hz Timeless??

Don't have the Timeless but I do have the Shuoer s12, which is supposedly quite similar (or definitely very very different, depending on who you ask). Having a hard time imagining who would be torn between the u554 and the s12, given that they have little in common besides price bracket and transparency, but hey, for what it's worth:

The s12 has a lot more body/"physicality" going on than the u554, as you would expect given the driver types. As my sig will tell you I have a bit of a thing for planars, and the s12 does "planar sound" quite well, with a wonderful combination of physicality and transparency. Side-by-side I think I'd put the u554 slightly ahead in terms of transparency alone, though that impression may just be due to the difference in tuning.

In terms of tuning, the s12 is a loose cannon next to the u554. Being a DF head I have to yank down the bass by about 8db and put some dents in the treble peaks to make the s12 enjoyable. Treble can get pretty sizzly without some correction. It EQs quite well, but I'm not enough of an EQ whiz to get it near the clarity and openness of the u554, if that is even possible in theory. (Also, it really makes me wish the EQ on my main DAP didn't cap out at -6db...) The u554's tuning, meanwhile, is just hands-off exquisite.

In terms of ergonomics, the s12 is an easy comfortable shallow fit, so no competition there. ^^;

 

[-rowan-]

These are fab impressions. My 554s are stuck at a consolidation centre somewhere in China but I can do the Timeless comparison when they do arrive, if no one else gets to it first. But like as @counterclockwise says, I don’t anticipate many being torn between the two. For one, these fishies sound like they image real well, if @ian91 ’s impressions are anything to go by, and that is not a forte of the Timeless.