HiBy x F.Audio Project Ace

Hiby Project Ace Review
Sources Used:

• Celest CD20
• Hiby R3ii (2025)

Build Quality and Fit

I have no complaints about the build quality of the Hiby Project Ace. For its price range, the materials and overall feel are excellent. The earphones have a full metal body, which feels solid and premium in hand. The cable is thick and sturdy. The carrying case is wrapped in leather with embroidered details and a soft velvet interior, giving it a luxurious touch.



In terms of fit, it's decent but not perfect. The Project Ace’s metal shells are quite bulky and rounded. Even with the correct eartips, while they do fit, they tend to feel a bit loose due to the shape of the housing.

Sound Character

The overall sound signature of the Project Ace is balanced—no part of the frequency range overpowers another. At my usual (low) listening volumes, it presents a neutral and smooth sound, thanks to its gentle midrange, upper mids, and treble.



Bass

Bass is primarily mid-bass focused. The Project Ace noticeably lacks sub-bass presence. The bass is present when needed and has decent rumble, impact, and speed. However, for example, in Billie Eilish’s "Copycat", the earphones fail to deliver that authoritative sub-bass effect in the intro.

Mids

Mids sound natural on both vocals and instruments like cellos and violins. I really enjoy listening to Apocalyptica with these. Vocals are neither forward nor recessed—they strike a balanced and natural tone. At higher volumes, the upper mids can become shouty or slightly sibilant, but at my usual low volume, I experienced no issues.

Treble

Treble is well-resolved with good extension. The biggest tonal issue for me is in the upper treble. It has a smooth and warm character, which affects the overall sense of detail, layering, and separation—especially upon first listen. Initially, it was hard to pick out micro-details. However, after spending more time with the Project Ace, I noticed that it actually has respectable micro-detail retrieval and decent layering. Still, it lacks the shimmer and sparkle that many V-shaped IEMs offer. Compared side-by-side with the Sennheiser IE600, for instance, the Project Ace’s treble is noticeably smoother.

Technicalities

The soundstage is wide, with good depth and excellent width, making it particularly enjoyable for classical music. Detail retrieval is decent, but due to the warm tonality, it doesn’t jump out immediately—you need to listen more attentively to notice its technical strengths. Layering is very good for this price range. For example, when listening to Adele's "Rolling in the Deep", I can clearly distinguish the background elements of the track.

Quick Disclaimer: I’m pretty sure you guys know the drill already especially if you’ve been reading my reviews that I also start with a disclaimer. Seems to be a bit redundant to mention everything else but hey it is what it is. I’m still a newbie and a casual listener to music and as always, this review is 100% my own, I did not read or watch any reviews prior to making this one.

The equipment I used for this review are the following:

• Spotify
• iPhone XS with Apple Dongle
• FX Audio R07 Plus
• Fosi Audio K7

I would like to thank HiBy for making this review possible! This is my 3rd product review from them and I’ve always been excited to try out their devices and this is me coming from reviewing the Zeta and R1. Looking forward to more reviews in the near future!

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And away we go~


This is my 3rd review from HiBy and coming from both the Zeta and R1, I can say that HiBy is one of those companies that I would recommend to anyone looking to start their audio journey or looking to explore different options from a variety of competitors. They have a wide range of options for anyone to choose from, looking for budget gears? No problem! Got money to burn? Yeah we can do that; and usually there’s a stigma that cheaper items would fall hard while spending a lot will get your money’s worth but that’s not the case for HiBy. Since Project Ace is a collaboration between HiBy and FAudio, I have high expectations on these sets since FAudio has been developing and manufacturing high-end earphones since 2015 with Ken Lee who is a music producer.

These IEMs come equipped with a single 12mm Mg-Alloy & Be-plated Dynamic Driver, again quite a surprise since these cost 249.99$. I was expecting maybe a dual driver or hybrid configuration with either planar or BA but a single DD? This reminds me of the Dynabird which also had a single DD but I was not disappointed and after listening to the Project Ace, I can say that this did not disappoint too. It would also seem that this batch that I received for review is continuing with the trend of having unique shell designs, the Project Ace has a shell that is CNC processed by cutting(I don’t know what that means but I’m guess it’s the same thing they did with the Dynabird’s shell), the faceplate has a sleek hexagonal shape with a reflective metal piece in one side which gives it a very nice contrast.

Despite the shell design to be sleek and unique on its own, I find that it lacks a groove in the nozzle to keep ear tips from moving around and that the irregular shape did give me some discomfort after long hours of continuous wearing. This is new to me as the Dynabird despite its irregular shape did not give me any discomfort, this may be different from other users but I find that the shape is the culprit.

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UNBOXING EXPERIENCE


The unboxing experience is a bit similar to that with the Zeta, the packaging has the black and gold colorway while still being simple; the specifications are not found anywhere in the packaging but removing the outer sleeve and lifting the top cover reveals a pamphlet which shows images and text about the specifications about the Project Ace and some lore about the IEMs. The IEMs are securely stored in a thick cut of foam with a separate case for ear tips, you’ll also get a box leather case with magnetic flaps which also contains the following:

• Premium Build Cable
• Divider
• 3.5mm and 4.4mm Modular Jack
• Cleaning Brush

You have 2 sets of ear tips, 3 sets of foam for bass and 3 sets of silicone which are for balance, props to HiBy for actually making a separate case to store the ear tips and not having them stored inside zip lock bags. The cable has a good amount of thickness to it but you will need to remove the divider that is inside the case if you want to fit these together with the Project Ace and hey it has the option to swap between 3.5mm and 4.4mm jack which is great if you have multiple sources except Type-C oh and they come with the standard 0.78mm 2 Pin Connector.

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OVERALL IMPRESSIONS

Using iPhone XS with Apple Dongle

Continuing with the trend of having a single DD the Project Ace is easy to drive/power; the overall sound quality is it has a slight bright tonality with a balanced tuning. Having a slightly bright tonality gives it a strong emphasis when it comes with vocals and instruments but thankfully the Project Ace is not shouty unless if listening in higher volumes then a sharp sibilance is present. Instruments can be heard with great clarity and detail, there is a good amount of sparkle present which caught me by surprise. Although the Project Ace emphasizes on both the vocals and instruments, there is no bleeding in between.

The sound staging is slightly narrow but it is a bit holographic. Sad to say that the panning in some songs is not great as it sounds like they are just walking from right to left rather than sounding that they are walking right behind you or directly speaking to you behind your shoulder, still I will say that the Project Ace does a good job. Imaging is also precise, each instrument can be heard in the direction that they are playing is noticeable.

Now we move to the bass, as stated the Project Ace has a balanced tuning with a bright tonality so bassheads will most likely skip this set. The mid-bass has a smooth yet a tiny bit of punch and the sub-bass does have a bit of rumble while maintaining a smooth texture. Again these will probably be ignored by bassheads but hey for a balanced tuning, you get the best of both worlds by having strong emphasis on vocals and instruments while still having a bit of bass.

Using Fosi Audio K7 3.5mm Jack

And now we slowly introduce the Project Ace to the big boys, starting with the Fosi Audio K7.

Vocals and instruments still maintain their slight bright tonality but have better separation. Vocals have great separation between the background and supporting vocalists, the same goes with the instruments which also have great separation and have a better clarity and detail while still maintaining a good amount of sparkle.

Thanks to the K7 for being a desktop DAC/AMP that focuses on gaming more than music, the sound staging got wider and more holographic, panning now sounds more off set and it is as if the vocals are speaking from your shoulder or when in gaming, you can hear that someone is definitely sneaking behind you. Imaging also had a huge upgrade making it sound accurate, being able to pinpoint where the sounds are coming from either gaming or listening to music gives a whole different kind of immersion.

How does the bass of the Project Ace respond to more power? Well, not much. It still maintains its balanced tuning and there were no significant boosts to both the mid and sub bass. While I could get away with this and change the K7’s option to boost the bass to +6, I choose to use the source in its purest form. Maybe there was a slight boost to the mid-bass punch and a little more rumbling to the sub-bass but in honesty, the differences are very minimal.

Using Fosi Audio K7 4.4mm Jack

In all complete honesty here, there wasn’t much change. A slight increase to the audio/power output and made the vocals and instruments brighter but not too shouty and not have any distortions. Separation between vocals and instruments remains the same as using the 3.5mm jack and yes the sparkle is still there too.

Sound staging also remains the same as well as the imaging. Perhaps the only difference between the 3.5mm and 4.4mm is that it has a higher volume so you can definitely hear more without having to increase the percentage of the K7.

You might think that there is no change in the bass response too but surprisingly there is. The mid-bass has a better bass response and smoother kick while the sub-bass has more texture to the rumble and just like the mid-bass, it is smoother too.

Using FX AUDIO R07 Plus 3.5mm Jack

Last but certainly not the least is the R07 Plus. The slightly bright tonality disappears making the Project Ace purely balanced. Vocals and instruments still have great separation though it has lesser clarity and detail due to the loss of the brightness, despite this the vocals sound more relaxed without any muddiness or distortion especially during high volumes, no sibilance can be heard.

Sound staging was reverted back to its narrow spacing which is a bit of a bummer since I really enjoyed what the K7 did to the sound staging; imaging also went back to being precise rather than being accurate but still retains a bit of a holographic quality. Each instrument can still be heard but it does lack a bit more on the imaging, something you can expect for a DAC/AMP that doesn’t focus a lot on sound staging but is a versatile gadget for your everyday use and listening.

Then we move to the bass which is better than the K7. Mid-bass now has a smooth yet punchier feel but it won’t shake your eardrums while the sub-bass got a much rumbly texture while still being smooth, listening to songs with a lot of bass can get a bit uncomfortable but overall it has that oomph bassheads will surely enjoy.

Using FX AUDIO R07 Plus 4.4mm Jack

Switching to the 4.4mm jack, I can immediately tell that there was a huge boost to the treble making it bright again. It is borderline shouty with strong emphasis on vocals and not so much on instruments, there is still a bit of sparkle present but it is not as prominent as K7, I would say it is the same as the Apple Dongle. Despite the huge boost to the treble and it being borderline shouty, there is no distortion and sharp sibilance. Instruments are somewhat being overwhelmed by the vocals but can still be heard with good clarity and detail.

Sound staging did have a slight boost making the area slightly wider. Imaging just got better and the holographic now has a slight offset making vocals and instruments sound as if it is being played behind your shoulders. The K7 still has a much better sound staging than the R07 plus but the Project Ace does a great job in handling anything that is being thrown to it.

The mid and sub bass got a huge boost, the mid-bass is way punchier while still maintaining a smooth texture and the sub-bass has a lot of rumbling texture which already shook my eardrums, I can already tell that this will cause some discomfort after prolonged listening.

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FINAL THOUGHTS

Before I end this review, I will be comparing the Project Ace to LETSHUOER’s Cadenza 4 which is a 249$ Balanced IEM.

Cadenza 4 vs Project Ace

Both IEMs have a balanced tuning right out of the box, the only difference between the two is that the Cadenza 4 focuses a lot in the sound staging and imaging making the overall listening experience wide and accurate while the Project Ace focuses on both vocals and instruments giving it a much better clarity and detail. In terms of the bass response, the Project Ace takes the win here by having a much punchier mid-bass and rumbling sub-bass than the Cadenza 4. If I were to personally pick between the two, it would be the Cadenza 4 despite it lacking in the bass response since the comfort and fitment it gives beats the Project Ace but I do see myself going back to the Project Ace if I want to hear more bass.

Overall, the Project Ace is another versatile IEM that is capable of accommodating any music genre that is being thrown into it with the exception of having a dedicated DAC/AMP to give it a bit more power especially when using the 4.4mm jack that comes with it. The price point of 249.99$ is justifiable especially with the shell design and accessories that it comes with and that the sound quality will satisfy pretty much anyone from treble to bass heads.

Blup blup 𓆟 and happy listening!

Hiby x Faudio Project Ace, review and comparisons.

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Hello, this is my review for the 249 USD Hiby x Faudio Project Ace in-ear monitor. Sent to me for a review, from a review tour conducted by Hiby. Thank you, Hiby.

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I wanted to know how this compares to my other single DD sets at this price range.

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It is a collaborative product of Hiby and Faudio; it is a single dynamic driver IEM with a driver that has an Mg alloy and Be plated diaphragm, which should make the resolution better than normally used PET material.

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It has a neat packaging that includes an elegant leather case; I wish they made it smaller to become pocketable, though. It also includes two sets of ear tips, a foam set and a silicone set. The included modular cable is excellent, one of the best I've seen in this price range. I wish they made it easier to see the left and right indicators on the 2 pins, though.

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For this review, I used various DAC/amps and DAPs, but mostly the iBasso DC Elite with my phone. I used the included silicone ear tips as I don't like using foam tips. I used the stock cable with the 4.4mm balanced connection. I never had issues with discomfort wearing it; it is very comfortable to wear.

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The sound signature is slightly V-shaped and energetic. The bass is punchy and appropriately boosted, and with the right amount of sub-bass extension, it has very good granularity, details, and texture. The midrange is very slightly lower in level compared to the bass and treble, which made the sound pleasant and not annoying to listen to. The note weight is good; it never rendered anything too thin nor too thick in note weight; it sounds just right. The treble is crisp, detailed, and resolving.

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It is average in sensitivity and can go loud with very low distortion, which is excellent in my opinion.

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In terms of its technical performance, the soundstage is medium-sized but above average in all the single DD sets that I've heard. The imaging is very good, with good separation between instruments; the holography is nice too, definitely above average for a single DD set regardless of price. I suspect the diaphragm material really helped here.

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Compared to Dunu Falcon Ultra Ti (220 USD):

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The Dunu Falcon Ultra Ti is a single DD IEM with similarly high-tech diaphragm material. I'm using it with ePRO EP00 eartips and a Dunu Lyre mini cable. The Falcon Ultra Ti is the most neutral-sounding set in this comparison. Compared to the Project Ace, the Project Ace has slightly more bass with more punch and more visceral impact. They are both neutral in midrange with similar details and resolution, but in terms of treble, I find the Falcon Ultra Ti to have slightly more extended upper treble; the Project Ace has good extension in absolute terms but sounds slightly dark in the upper treble on average. In terms of imaging, the Falcon Ultra edges the Project Ace slightly; the Falcon Ultra also has a slightly bigger soundstage.

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I suspect that Project Ace needed more burn-in time for it to improve, especially because it uses more rigid than normal diaphragm material. Well, not all people believe in burn-in, but I found my Dunu Falcon Ultra Ti and Simgot EA1000 improved in sound quality a couple of months after using them; unfortunately, I don't have the luxury of time to do that with the Project Ace, as it is a review tour unit and had to be passed on to the next reviewer in a week or so. But as it is now, I like the bass and enthusiastic energy of the Project Ace over the Falcon Ultra Ti.

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Compared to Simgot EA1000 (219 USD):

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The EA1000 is a very popular IEM in this price range; thus, I have to compare it with the Project Ace. The bass in the EA1000 is very neutral and slightly lower in volume level compared to Project Ace's. The EA1000 has a more airy general sound presentation; it has a slightly less warm midrange and has a more boosted upper treble. They are similar in imaging performance, but I found the EA1000 to have a wider soundstage. I use ePRO EP00 ear tips on the EA1000 with the Tripowin Seraph cable. Sadly, I didn't have the time to experiment with other ear tips on the Project Ace because, as I said earlier, it is a tour unit and has to be passed on to the next reviewer.

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Pros:

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+Very good bass

+ Energetic-sounding

+Engaging

+Excellent build quality

+One of the best-looking stock cables for the price.

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Cons:

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-Slightly dark upper treble


-I wish for more upper treble delicacy, gentleness, and micro details, but I suspect this could improve with more burn-in, but unfortunately I don't have the luxury of time to burn it in for months as it is a tour unit, unlike the other sets in the comparison. which I found to have improved in sound even after a couple of months of using/burn-in.

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Conclusion:

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The Hiby x Faudio Project Ace is a very nice and complete set. The sound is very good for most music genres. I especially like the bass, the crisp treble, and the energetic sound it produces. I think it is worth its price and should be considered when shopping for an IEM above 200 dollars in price.

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That, my friends, concludes my review of the Hiby x Faudio Project Ace.

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Happy listening, cheers!

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Non-affiliated purchase link:

https://store.hiby.com/products/hib...bPtSoYoOLpW_pDMgQy-WWY77HVM-8n7Ig-eCQ1dE8g09w