NGaudio Erebus

[These impressions were originally shared on the Watercooler thread, revised for converting to this review.]



What follows is a set of impressions comparing Erebus to three similar IEMs. It isn't exactly a review but Erebus needs more love and exposure, thus these reflections go here.

Who am I? I'm not a reviewer, just an appreciator of great sound and gear, and I like to share my thoughts with fellow listeners and portable audiophiles. I have pretty wide-ranging music tastes and preferences for sound quality and gear performance. My tastes tilt to the TOTL end of the portable universe.

I have spent the last few weeks listening to four IEMs that share many similarities: Annihilator 23, Fei Wan, Loki, and Erebus. I’ve focused on the first three in several comparison posts recently. Now it is Erebus’ turn in the spotlight. Many people may be saying “Ere-what?” since this is such an unknown in circles like Watercooler and seemingly the rest of Head-Fi. This is definitely a TOTL IEM, and in a universe where that expression may be overused, Erebus stands out.

I will note that NGAudio has done itself and the portable audiophile community no favors with its lack of marketing. I have heard it is more widely known in China and parts of Asia. But why release a $4700US retail IEM in all other markets just to let it languish, unknown and unheard? It is a shame particularly since it is a fantastic IEM, and I personally would love to have more of you to banter with about the Erebus in the same way we all dish on newer hot properties like Canpur 622B, Annihilator 23, Storm, Trifecta and more.

Putting that aside, I truly enjoyed listening to the four IEMs at hand over the past few weeks. It’s been an absolute treat to have access and time to put them all through my gauntlet of test tracks. All four share the so-called Asian/Eastern top-down profile, and with solid to great DD bass. Their retail prices range from $3000US to $4700US, which to feels random to me since they are all very close in performance and joy factor, with some key distinctions.

Note that in my comparisons, when I say “Anni” I mean Annihilator 23. When I say Loki I am referring to the international edition.



Setup:
My test chain for Erebus was N30 DAP (hyper off, A/B amp, P)>doctorjuggles copper cable>Erebus>Azla Max tips. I used N30 to test the other three IEMs for this round.

Erebus is relatively easy to drive, almost the same as Loki. Fei Wan requires less power. Anni requires a lot more juice to sing.

I am a big fan of @doctorjuggles custom cables - in particular his copper cable tops some I have on hand with Erebus, including First Times Shielding (too much energy), Cleo II (too little bass), and stock (too little of everything).

Music:
A mix of classic rock, modern rock, folk rock, singer/songwriter, jazz vocal, jazz, pop, dance pop. The genres I don't listen to much and were excluded from these impressions include EDM and other electronic subgenres, hip hop, and classical. All the same test songs I used in my other recent comparisons between Anni 23, Fei Wan, and Loki.

Build and Fit:
Premium build. The Erebus shell feels like a small piece of polished marble.

The plate design is not super attractive, and I never would have chosen this on looks alone. That said, appearance doesn’t matter much to me, since I don’t see a IEM while it is in my ears and it is otherwise stored safely in a case.

Erebus is almost as comfortable as Fei Wan, making it more comfortable than any other IEM I have tried except that one. I could have Erebus in all day and barely notice.

Nozzle width is medium, so no difficulties putting on tips.

The 2-pin port is not recessed so it feels tenuous when I am attempting to insert a cable. Recessed would have been easier and felt more secure.

Slight DD flex on insertion.
No pressure thanks to venting.

Sound Profile:
Erebus has a more relaxed sound than other three but is not relaxed in absolute terms: it has some verve, scales extremely well, works with just about any type of music, for any mood I brought to it.

It features a largely uncolored, very slightly warm, reference-ish sound (its bass strength and upper mids energy keep it from being what I imagine truly reference style to be).

At first it does not sound really special, rather just very good, but with more extended listening, the full scope of how impressive and top-shelf Erebus is becomes clear.

Erebus features a more balanced W shaped sound than the other three. All parts of the FR are distinct and still coherent, unlike some other W shaped IEMs like Rn6 that to me sounded slightly less coherent.

Erebus’ sub bass has punch and snap, close to FW, moreso than Anni and Loki. More articulate and tactile sub bass than Anni and Loki, though not quite as much as FW. Medium decay, as opposed to FW or Loki.

There is a medium amount of mid bass, not close to FW’s, also less than Loki, and more similar to Anni. Erebus’ mid bass comes up to lower mids just enough to bring them a bit forward and add depth and a little warmth. No muddiness across the spectrum.

Erebus’ mids are the best of the set of four. Its mids are more forward than the other three, with what feels like just the right amount for vocals and acoustic instruments to assert their space well and not be left behind, as can be the case with Loki in particular. Erebus’ mids are neutral-ish but still have excellent texture. To go beyond the set of four in these impressions, and going from memory, I find Erebus' mids not to be as warm and romantic as Trailli's. I find its mids however to be as detailed and similar-charactered as Mentor's.

The upper mids can be energetic at times, though not peaky and generally not fatiguing. This quality lends urgency to many vocals, which 90% of the time is welcome. Still, I would prefer it was dialed down. At points the danger zone is approached, but never fully entered into thankfully.

Erebus has fantastic treble, not dry but rather neutral to slightly sweet, loads of air with just the right sparkle, softened crispness, medium extension, zero sibilance, not at all fatiguing. Very close to Anni’s treble, I would say 95% of it, just lacking a very slight bit of the superior transient snap that Anni possesses. Erebus’ treble to me is better than Fei Wan and Loki, as excellent as those two are in the higher end.

Erebus’ timbre is more neutral than FW, equal to Anni. Realistic, minimal color. More how the music was intended perhaps (as overused an expression as that is).

Emotive listening experience, very musical and not at all clinical, even with its relatively neutral sound profile.

Technicals:
Superb technicals, maybe the best as an entire presentation of any IEM I have heard (note I have not heard Storm, Jewel, Canpur 622, or Amber Pearl, which are also described as technical frontrunners).

Excellent layering and separation of instruments, better than the other three, in spite of their excellence. Superior imaging as well.

Wider stage than the other three, though Fei Wan is very close. Compares to other staging class leaders like Trailli, which is on par, and Mentor, which has massive 360 holographic staging, more than Erebus. Stage not as deep as FW. Deeper than Anni and Loki.

Dynamics are solid but Fei Wan is a dynamics monster, and Erebus isn't quite at that level. It is on par with Anni and Loki's dynamics performance.

Excellent transients, particularly acoustic and brass instruments, slightly behind Anni, on par with Fei Wan, better than Loki.

As much or more detail than other three, which is saying something as these are all extremely resolving IEMs.

Equal speed to the other three.

Vocals:
Maybe the best part of Erebus’ performance. Up and down vocal ranges, it scales so well, from Ella Fitzgerald ballads and Sarah Jarosz’s singer/songwriter songs, up through faster and more robust vocals such as Robert Plant on Led Zepplin’s “Immigrant Song” and Beastie Boys “So What’cha Want”, and more baritone voices like Gregory Porter on “Liquid Spirit” and Paul Simon’s background singers on “Diamonds On The Soles Of Her Shoes” - so many Wow moments. All across the vocal spectrum, I hear excellence of pacing, timbre, intonation, detail.

Best Genres:
All of them! (or at least all the genres I listen to)
Jazz and bass vocal sound superb
Classic rock, modern rock, pop, dance pop: all excellent
I suspect classical would sound terrific, though I don’t listen to it
Live music sounds fantastic - Wynton Marsalis Septet at Lincoln Center with many guests sounds exhilarating and enchanting, perfection in my mind. In terms of scaling, The Who “Live At Leeds” sounds vigorous, fast and alive on Erebus, on par with Fei Wan even without FW’s full bore bass intensity.

Conclusions:
Erebus is most similar to Annihilator 23 out of the other three. The key differences are Erebus has for me much better bass performance, more forward and textured mids, and much larger staging. The rest of the technicals, such as detail and transients, are similar. All of that with treble that is almost on-par with Anni. These two IEMs are similar enough that I would not include them both in the same roster.

Erebus makes an excellent complement to the other two, Fei Wan and Loki. It makes an even better apples and orange complement to Trifecta, which I also have. I would say Erebus plus any “fun” IEM like Fei Wan or bottom-up set like Xe6 or maybe Raven (which I haven’t heard yet) would be a great two-IEM tag team.

Erebus is the most all-rounder of any in my roster, with Anni closely behind. Any genre from my library that I play, with any tempo or level of complexity, sounds excellent on it. It scales better than the other three, better than any IEM I have heard.

As others have mentioned, Erebus is a bit of a slow burn as far as recognizing its amazing qualities. After a handful of listening sessions of "this is good but not great" and allowing Erebus to burn in, it became very evident what a special IEM this is. Erebus rewards patience, but not too much is required.

I realize my impressions have been almost entirely positive to raves. I don’t mean to be a fanboy about the Erebus, I just can find few flaws for my preferences. One would be the plate design, not a big deal for me but still it is not attractive. The lack of recessed 2-pin connector ports is not great. It is expensive at $4700US retail. The other nitpick is the energy in the upper mids, which if they were slightly reduced would make this the IEM I could quit the hobby with. Even still, it very well could be if that sad day were ever to come.

Hopefully more of you will get to hear Erebus. It is first-rate and should be in the conversation when we all debate which are the TOTL of TOTLs in the IEM world.

NGaudio Erebus

About Me: I am passionate and thoroughly find joy in providing feedback on products to help other hobbyists along their journey. Trust only in YOUR ears. Music has been, and will continue to be, a huge part of my life. My escape from the frustrations and static of everyday life. I typically listen to Metal (progressive/ djent/ deathcore/ hardcore) alternative and classic rock. Music with meaning, emotion, and polyrhythms! Music dedicated to pushing the limits of what we thought was possible.

Introduction: Since there is still little known about NGaudio here in the West, I’ll start by giving a quick summary of the brand’s history. NGaudio is a custom IEM manufacturer based in Shenzhen, China. Since 2015, founder Wu Chenlong and his team have been hard at work developing award winning headphones in their pursuit of the perfect sound. From what I have read, NGaudio’s core team is comprised of 5 individuals. In a geographic location packed full of Chi-Fi mega manufacturers, I was pleasantly surprised to see a ‘boutique’ brand holding their own. If you’re not familiar with ‘chi-fi’, just know this. If your technology can be replicated, cheaper versions will emerge. Bottom line, it is reasonable to assume that NGaudio isn’t just pushing out some recycled, run-of-the-mill tech. There is some serious magic under the hood, and I can attest. After purchasing the ‘Khoas’ a few months back and absolutely falling in love, I had to see what else NG had to offer.

Introducing, the Erebus



Product Overview: NGaudio Erebus (Universal)
- Released Date: November 11, 2022
- Retail: $4,799 USD
- Driver Configuration: 15 unit/ 4 frequency division/ 4-way split design
1 low frequency (DD) + 4 mid frequency (BA) + 2 mid-high frequency (BA) + 8 high frequency (EST)
- Sensitivity: 104db SPL@1mW
- Impedance: 17 Ohms
- Frequency Response Range: 5-70kHz
- Stock Cable: Custom/ OFC/ 4W

Packaging Accessories

• NGaudio signature IEM case
• Pair of NGaudio Erebus IEM’s
• Custom NGaudio silver plated copper cable
• (4) desiccant packs
• Cleaning tool
• (3) Velcro NGaudio cable organizers
• (1) full set of generic tips
• ‘Warranty Certificate’ Card

Build Quality (5/5)
Starting with the overall aesthetics, the Erebus shells are one of a kind. The faceplates feature a three-dimensional injection of a white, silver and purple resin, finished with the brand's standard gold print text. The housing of the IEM is black, with an NG signature at the rear. Each shell is vented and equipped with a non-recessed 2-pin. The nozzle is on the larger side with 4 open ports. The overall feel is smooth with no raised or apparent edges and overall construction is rock solid.

Fit (5/5)
I would classify the overall size of the Erebus as large but well designed. Its nozzle depth allows for a comfortable, well-supported fit, just close enough to the outer ear to not look ridiculous. I did have to tip roll to find that perfect synergy between comfort and sound but once my selection was made, I had no issues wearing for hours.

Cable Quality (3/5)
Similar to the cable provided with the Khoas, I’m not blown away. Aesthetically, I would have preferred a silver cable, but I do appreciate the addition of branding and the overall ergonomics. I couldn’t find too much information on the stock cable beyond it being OFC. I do agree with the pairing of an all-copper cable from my personal testing as well. From a performance perspective, the cable provided is a good match.

Accessories (3/5)
Case: The leather puck style case is functional, well-constructed and performs its job.
Cable Organizer(s): My opinion, velcro organizers are typically provided when a manufacturer is aiming to cut unnecessary costs. This is almost a $5k IEM... I would have expected a leather organizer.
Eartips: Included is (1) set of generic silicone ear tips.
Additional: Cleaning tool and (4) desiccant packs
Wishlist: IEM shell sleeve/ Leather cable organizer/ Name brand eartips/ upgraded cable

Sound
Personal Taste: Bass. I need to feel my music. There needs to be a distinct separation and accurate layering of instruments. I need to hear that bass guitar! This is the sonic link between the rhythmic and melodic elements in music. Vocals are generally less important to me but need to sound natural. Treble should be well extended with an emphasis on presence, air, and overall detail retrieval. I find myself somewhat sensitive in this region and absolutely despise shouty, sibilant IEM’s.


(Measurements provided by Twister6)
Disclaimer: I want to emphasize that graphs do not paint the entire picture. It is imperative that you know the aspect ratio of the graph, y-axis range, normalization used, and how much octave smoothing was used. FR graphs are a great visual reference when trying to communicate certain aspects of an IEM’s tonal balance, but a great looking graph does not always mean a great sounding product.

I listened to a wide range of music while developing my assessment. Before putting anything down on paper, I spent over 50 hours casually and critically listening from various sources. I found the NGaudio Erebus to be extremely well balanced, tonally accurate, with a modest boost to the bass and treble region.



Bass: The Erebus delivers a seriously satisfying low-end experience. The low end is thunderous, well-controlled and complimentary to all musical aspects. It’s almost like the Erebus knows what you need and when you need it. If I’m playing a more bass focused track, the bass comes through with just the right amount of rumble and weight at all volume levels. When listening to a more balanced composition, the low end adds just the right amount of texture to notes without bleeding into the mid-range or affecting the overall sound stage. In my opinion, this is where a lot of bass boosted IEM’s fail. I’ll use an exaggerated example and graphic to help explain my non-scientific assumption.

First, it’s important to remember that different drivers are responsible for different frequencies (minus single DD sets). Let’s assume IEM (X) has a wide sound stage and the ability to accurately place symbol strikes (High frequency fundamental tone) to the far left and far right BUT the low harmonic frequencies (undertones) of each strike are perceived more center stage. So, when all tones are presented simultaneously, the sound stage width and/or height is perceived closer to center stage.


This is the best I can do without posting a lesson in fundamental frequency and harmonics frequency. The point I’m trying to make is the Erebus has excellent imaging capabilities across all frequencies, maintaining its expansive soundstage.

Midrange: I wouldn’t consider the mid-tonality of the Erebus to be warm or cold. To me, the mids sound neutral with great instrumental timbre and speed. The lower-mid presentation is accurate and uncolored. The upper mids are slightly elevated, providing clear instrumental separation and a forward vocal presentation. What I love most about this IEM is its ability to maintain such a neutral tonality without sacrificing texture or a level of excitement.

Treble: The treble region is almost a perfect representation of my preference. Accurate, airy, well extended with a conservative dash of sparkle. At no point did I find the Erebus overly sharp or sibilant. If you prefer an abundance of sparkle and emphasis to the upper treble region you might find this tuning a bit ‘boring’.

Technicalities: The Erebus has surgical imaging capabilities and one of the widest sound stages I’ve ever experienced. Resolution is top tier, as it should be at this price. I’d love to critique here but I’m struggling. For such a ‘neutral’ leaning sound signature, it’s impressive how technical this IEM really is.

Eartip Selection
Listed in order of preference

• SpinFit CP500 - Enhanced sub bass depth and presentation. Best fit, seal and overall balance of the bunch.
• Final Audio Type E - Provided the most bass of all tips tested. Slightly smaller sound stage width and height.
• SpinFit CP145 - Slight reduction to sub bass impact but sounded fantastic otherwise. Similar to CP500, just less bass.
• Eletech Baroque – Fit was my main issue here. The Erebus nozzle is smooth so I continually had to readjust the placement of the tip on the nozzle. Slight reduction to sub bass, elevating upper frequencies.

Preferred Source
Listed in order of preference

• Sony NW-WM1ZM2 - 4.4 Balanced/ High Gain/ Direct Source
  • Pros - Best technicalities/ Enhanced natural tonality/ Noise floor is non existent
  • Cons - Slight reduction to low frequency impact

• Cayin N7 - 4.4 Balanced/ High Gain/ Class A/ DSD 512
  • Pros - Great technicalities/ neutral source
  • Cons - Slight reduction to sound stage when compared to 1ZM2. Low(er) note decay

• Astell&Kern SR35+PA10 - 4.4 Balanced/ Quad DAC/ High Gain (PA10)
  • Pros - Most analytical presentation/ Slight low end emphasis
  • Cons - Two devices/ Noticeable noise floor introduced when paired with PA10 Amp

• HiBy RS6 - 4.4 Balanced/ High Gain/ Darwin Ultra Filter
  • Pros - Darwin V2 filterset for fine tuning sound
  • Cons - Warmish tonality does not pair well Erebus

Comparisons
For my comparisons, I selected several other V-shaped flagships and a member of the NGaudio family (Empire Ears Raven/ FatFreq Grand Maestro/ NGaudio Khoas). Comparisons were conducted while listening to the same song(s) - Volume matched on the same source chain.


NGaudio Erebus (SF CP500 Eartips/ PWA Purple Charm V2 Cable) Vs. FF Grand Maestro (SF W1 Eartips/ Liquid Links Evua II Cable)
Prelim: In my humble opinion, the FF GM is one of the most versatile IEM’s on the market. The GM’s V-shaped signature is more pronounced when compared to the Erebus.
Fit: For me, the biggest con of the Grand Maestro is its size and shape. The shell sizes of these two IEM’s are actually quite similar but the GM’s nozzle is longer and extends perfectly straight off the shell. The Erebus’s nozzle is probably 1/4” shorter and angles slightly upward, seating more naturally in the ear canal.
Sound: The soundstage of the GM has less width and height. Detail retrieval is slightly fainter with the GM but this accentuates its soundstage depth. GM’s sub bass is definitely more prominent. Both have a deep, rich rumble. Mid’s come off thicker/ warmer on the GM while notes on the Erebus have more weight. Both have a similar vocal presentation. Slightly forward but well placed within the overall mix. GM’s treble emphasis results in more sparkle but its clarity is definitely impacted by its boosted low end.
Conclusion: The GM is more energetic and targets a more traditional V-shaped signature. The Erebus has a more natural balance across all frequencies but still gives you a satisfying dose of bass. I was not a fan of either sets stock cable. To fully experience what each set has to offer, I would highly suggest an aftermarket cable.


NGaudio Erebus (SF CP500 Eartips/ PWA Purple Charm V2 Cable) Vs. EE Raven (FA Type E Eartips/ PWA R7 Cable)
Prelim: Similar to the Grand Maestro, the Raven has a more pronounced V-Shape tuning but also features some unique tuning characteristics. Where EE has a more established ‘house sound’, the Erebus aims for realism. I should note that the Raven is almost brand new, with only a few hours of burn in.
Fit: The EE Raven is the largest IEM I have ever handled. This thing is a beast. When doing a side by side comparison, both share a similar shell width and nozzle length. The nozzle of the Raven extends slightly forward and up, less pronounced compared to the Erebus. Both fit very good given their size. One last thing worth mentioning is the presence of driver flex with the Raven. I freaking hate it.
Sound: Both sets have a very impressive soundstage. The Erebus has better instrumental separation and stereo imaging but this could due to the lack of burn in. My previous set of Ravens had roughly 20 hours on them and I do remember being extremely impressed. The Raven’s low end quantity falls somewhere between the GM and Erebus. From a personal preference perspective, the Raven’s hit the spot. The Ravens mid range is thicker and produces a slightly abnormal timbre with some instruments. This is likely due to the Ravens 400Hz spike. The Ravens treble is the spiciest of the bunch but wow does it sound fantastic. I wouldn’t consider either set to be sharp or fatiguing.
Conclusion: The sound signature of the Raven is fun, energetic and extremely engaging with a less natural tonality. The sound signature of the Erebus is more polite, balanced and organic sounding. If I wanted to rock out, I’m reaching for my Raven’s. If I want a more natural, uncolored representation of my library, I’m grabbing the Erebus.


NGaudio Erebus (SF CP500 Eartips/ PWA Purple Charm V2 Cable) Vs. NGaudio Khoas (SF W1 Eartips/ PWA Attila Shielding Cable)
Prelim: The Khoas was the previous flagship offering by NGaudio prior to the Erebus’s release. If you have followed any of my recent reviews, you know that I find the Khoas extremely impressive. For context, the Khoas features a more W-shaped sound signature.
Fit: The Khoas is slightly smaller when comparing the two IEM’s side by side but both share an almost identical shape and nozzle. Both are very comfortable.
Sound: The soundstage of the Khoas is more intimate. Instruments sound closer, giving the stage of the Erebus more depth but I don’t notice any loss of width or height. Both sets grant you TOTL resolution. The low end of the Erebus is slightly more pronounced while the mid range comes off a bit thinner and more neutral sounding. The Khoas has a bit more energy and thickness to its mid range. Both have excellent instrumental and vocal timbre. The treble of the Khoas is a bit more exciting but both sets are well extended.
Conclusion: This really just bakes down to preference. The only real differentiator, which applies to every set I’ve compared to the Erebus, is note texture. The Erebus just does a wonderful job at representing every detail, every nuance, every note as if it’s just as important as the others. If I was listening to an album that required a more energetic signature, then I’d grab the Khoas. Otherwise, I’m happy with either.

Summary
At the end of the day, the Erebus is a luxury item most folks can’t or are unwilling to buy. It’s price tag is eye watering... But if you want to hear, what I consider, the most realistic, uncolored presentation of your music, this is it. Some will find it boring, I have zero doubts. I think this IEM best suites classical/ Jazz/ Rock/ Metal but can still be enjoyed playing back almost any genre of music. Personally, I can’t wait to hear what comes next in NGaudio’s pursuit of the ‘perfect’ sound.

If you’re interested in purchasing a set, please find the link below.
MusicTeck - NGaudio Erebus