ISN Audio NEO 5


Headphoneus Supremus
ISN Neo 5 Review - Purple Bass
Pros: + Warm, bass-heavy tuned all-rounder
+ Non-fatiguing sound and comfort for every day, all day use
+ Easy to power with any source
Cons: - Not for treble heads
- Bass is slow and inarticulate
- 2pin connection issues

ISN Neo 5 - Purple Bass​

I have been using the Neo 5 for around 6 months, 4 of which were full time. It's a 1DD x 4BA configuration.

They were purchased through AliExpress on a sale with my own money.

A little about me...
I am a mid 30’s dad, and work full time in IT. Music has been important to me from a young age, consuming as many different types of albums and genres as I could. That is still true today, though my every day playlists lean most in pop, bass heavy electronic music, metal, and classic rock. I have a treble sensitivity due to years of negligent concert hearing protection (both on and off stage), so my preferred sound signature is warm and bassy. This is just a hobby for me, and I will always state how and where I got my gear.

Gear used for this review -
ivipQ-140 Cable / Stock white tips / Cayin RU7 / Schiit Magni + Modi+ stack / Qudelix 5k


Aesthetics + Build Quality + Accessories

With the translucent purple and gold branding, at first sight the Neo 5 spoke to me. It reminded me of an old Nintendo 64, and when I heard it was bass tuned I knew I had to have one. It's an elegantly simple looking set, with the full innards of the drivers on display. The resin shell is small and shaped to fit the ear comfortably. The shells feel high quality, and are not easy to scratch or mark up. On the back of each shell is a small vent hole, marked blue/red for left/right. I would have preferred no coloration but its hardly an issue. The nozzles are small and have a metal mesh, and can fit most any tip easily. The 2-pin connection is not recessed, and was VERY tight when I first got my set, on the left side. I was concerned about breaking it when removing it the first time or two, but it did loosen up... a bit too much, 6 months on and a few cable swaps later. It hasn't been an issue where it has fallen off, but I would be mindful of it when cable swapping.

The Neo 5 came with an S4 cable, small carrying case and variety of tips. I prefer the sound of the white ones more, to my ears they are a good balance in sound by thinning out the bass a bit. Both of the stock tips have been used with other sets, Penon makes high quality tips and it would be wise in invest in some regardless! The carrying case is a nice blue leather with a magnet top. It's a little too small for my use, but if you just want to carry around an IEM and that's all it would work for that. The S4 cable has a couple minor issues, no ear hooks, the right wire is a smidge longer than the left, and the chin slider does not hold.




The star of the show, the Neo 5 is tuned around it's full-bodied bass. With a winning combo of sub rumble and mid bass thump, it's stereo-like presentation hits hard and envelops the rest of the frequency in warmth. The first word that came to mind to describe it was "bulbous" and I believe that is an accurate description. For as much bass as there is, the bleed into the mids isn't as much as you would imagine. It digs deep, but the decay sticks around for a bit too long. My biggest gripe is with how slow the bass is, on faster tracks like metal or drum and bass it sounds very inarticulate/disjointed with the rest of the mix.


The mids have a thick note weight. Vocals, while not exactly recessed, take a back seat whenever they need to share the stage but both male and female vocals sound crisp and clear (male more so in my opinion). The mids are never thin, and on slower tracks (acoustic, vocal) you can really get a sense of how articulated and beatiful the mids are put together. The only time this changes is on the faster BPM tracks I mentioned earlier.


While I would call the treble the weakest link in the tuning, its far from being bad. It extends far out, but lacks the details and sparkle a treble head would look for. I have never considered this set as sibilant in any form, it leans warm like the rest of the tuning but there is zero BA timbre, everything is natural. Things like cymbal crashes are recessed, but I never felt like I was missing sounds in the higher register. I would recommend a wide bore tip to elevate the treble a bit.



The soundstage is wide, but not as deep, or tall. The bass adds to the width, bassier tracks typically "feel" grander than songs without as much. Instrument separation is good but not fantastic, as are the details. The Neo 5 isn't a technical monster, but it isn't supposed to be; it's for a smooth, engaging listen and it excels on every front in that regard.


Impedance: 26 Ω - 1kHz
Sensitivity: 110 ± 3dB - 1kHz

The Neo 5 isn't just a great sounding all-rounder, it's low power draw allows functionality with any DAC/dongle you utilize. I recently upgraded to 4.4mm cables, but with this set it is not necessary, a 3.5mm is fine. I use low gain on everything with it.


Final Thoughts​

It's not perfect, but I love my Neo 5. It's my go to IEM for out of the house due to its ease of use, low power needs and fun bassy sound signature. Commonly I use it for gaming on my Steam Deck, or watching movies when I am traveling on my iPad. At this point, newer and shinier things have hit the market but I feel like the Neo 5 deserves a little more recognition. It would make a fine addition to any collection missing a bass set.

ISN Neo 5 for $289.99 on Penon Audio
Nice Review! :) I love that ivipq-140 cable <3 Can you please tell me if it is really lighweight? Especially the split + chin slider which usually pulls down the most when it is too heavy
@rinderkappajoe really light cable, the splitter isn't fully metal. It has some plastic to keep the weight/cost down.

thank you!


Reviewer at hxosplus
ISN NEO 5 Review
Pros: + Bass emphasized tuning
+ Dynamic and impactful low-end
+ Present mids and smooth treble
+ Easy going and forgiving
+ Wide soundstage
+ Lightweight and comfortable
+ Good quality cable
+ Accessories
Cons: - Bass is rather slow
- Low-end could use more layering and definition
- Not the most sparking treble
- Flat soundstage
- Cable is not modular
ISN NEO 5 Review

ISN Audio is an earphones brand exclusive to Penon Audio with many successful products like the ISN H30 and their flagship, the ISN EST50.

The ISN NEO 5 is a new hybrid earphone with 5 drivers per side. A 10mm dynamic driver for the low frequencies and 4 Knowles BA drivers for the mids and the highs.


Non Audio Stuff

The ISN NEO 5 ear-shells are made from medical grade resin in a semi-transparent purple color. They are anatomically shaped with a custom-like design following the natural curves or the ear.

The ear-shells are lightweight, durable and well made. The fit is tight and comfortable, you can wear them for hours without feeling annoyance and moreover they provide good passive noise attenuation.


The 1.2m long, 2-pin, detachable cable is made from single crystal copper silver-plated wires in a four strand design. It is a well made cable with high quality aluminum plugs that is durable, soft and free of microphonic noise. You can order the cable with either a 4.4mm, 2.5mm or 3.5mm plug, the review sample came with a 4.4mm balanced plug.



The retail package includes a premium carrying case with a magnetic lid, three types of silicone ear-tips in three sizes each, a cleaning brush and a shirt clip.


Audio stuff

The impedance of the ISN NEO 5 is 26Ω and the sensitivity 110dB so we are talking about an earphone that is pretty easy to drive and at the same time quite immune to source noise.

With the FiiO M15S, low gain was more than enough while portable sources like the Cayin RU-7 or the iFi Go bar made them sing without much effort.

As per usual practice the ISN NEO 5 was left playing music for about 80 hours before listening evaluation.

You don't have to listen a lot in order to realize that the tuning of the ISN NEO 5 is emphasized towards bass. At the same time though, the mid-range is crystal clear and well defined, followed by a mildly smooth, but not that lacking in extension treble.

The low end gets the lion's share, it has a subwoofer-like extension and plenty of emphasis up to the lower mid-range. It isn't devoid of some mild bleeding but the overall impression is of a bass that it is not too overpowering over the rest of the frequencies thanks for the good driver coherency.

The bass is weighty, full bodied and visceral with great dynamics and physical impact. It is a mostly tight and well controlled bass but the recovery is not that fast while you can hear a mild echo.

The overall low-end balance is not that restrictive for listening to acoustic bass instruments however some of them, like the double bass and the cello sound rather colored and less accurate than they should be. Additionally there is a lack of definition and layering, especially during rapid bowing passages or when multiple instruments are playing together.

The mid-range is surprisingly crystal clear and transparent, with strong presence and not suppressed by the boosted low-end. The tuning is mostly balanced without any significant upper mid-range emphasis nor any notable recession. Voices and instruments sound smooth, well defined and articulated with plenty of harmonic variety and good timbre realism.

The treble is vibrant and energetic with ample extension, yet smooth, polite and mildly forgiving. Not the most analytical and sparkling earphone but still quite resolving and with the benefit that it never sounds fatiguing or bright. The treble has a rather weighty texture, it is not dry or lean, the timbre is good without any significant BA artificiality or metallic harshness.

The soundstage is wide and spacious with plenty of air around the performers who are accurately positioned in the horizontal plane. There is not much of a depth though the layering is nothing special and the presentation is quite intimate.


Compared to the ISN EST50

The ISN EST50 is the brand’s flagship earphone with a hybrid configuration consisting of 1 dynamic, 2 BA and 2 EST drivers per side. The physical appearance is the same as the NEO 5 and the ear-shells are identically shaped. The ISN EST 50 is slightly bulkier and a bit heavier than the NEO 5 which is marginally more comfortable.

Both earphones share a lot of similarities regarding their tuning. The bass is slightly less elevated in the ISN EST50 so it is a bit more correct and tonally accurate than the NEO 5. Technicalities are also better, the ISN EST50 is more tight and controlled, a little faster with better definition and less of reverberation.

The mid-range of the ISN NEO5 is more present and engaging with a fuller texture but the EST50 sounds more refined and resolving. The treble is smoother on the EST50 and maybe less energetic and extended but it is of higher quality and with greater timbre realism.

The soundstage of the ISN EST50 is wider, deeper and more holographic than in the NEO 5.

The ISN NEO 5 is actually a very good sounding earphone, especially if you prefer emphasized bass and present mids, but there is a good reason that the ISN EST50 is the flagship.


The ISN NEO 5 is a comfortable and well made earphone with an agreeable tuning that has plenty of bass and an easy going nature that makes it suitable for everyday listening of most kinds of music. It would not be my first choice for listening to classical music or jazz but it is really superb for electronic, rock and pop songs where it sounds very engaging and enjoyable with an inherent vibe.

The ISN NEO 5 was kindly provided free of charge in exchange for an honest review.
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Wide soundstage or flat soundstage ?
@laleeee Wide and open sounding but not that deep in layering.
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Headphoneus Supremus
The ISN Neo5s - So you like bass huh?
Pros: High chance they'll turn you into a basshead
Cons: High chance they'll turn you into a basshead
I've always wondered if there's an underlying audiophile stigma towards bass.

Do we politely nod our heads when others confess their lust for massive woofers, but privately scoff & assign them second-tier status because they choose to prioritise lower frequencies?

Certainly it's true newcomers to the hobby are frequently bass-obsessed, whilst its been claimed long-time audiophiles often become midrange aficionados. I suspect there's far more to it, and that one's taste in music plays the greater role.

So almost with a sinking heart I noted Penon Audio offering to send me a pair of thumping ISN Neo5s in exchange for a review, threatening to drag me deeper down a whirlpool of bass-driven degeneracy my audio cred may never survive.

Did I plug my ears & mime mantras at 15khz to resist all temptation, or have I mutated into a naked cultist of the heathen Bass Gods, howling blasphemous incantations into the night as we dance around a bonfire of bongos & tom-toms? Read on if you dare!


The ISN Neo5 are a set of USD $289 earphones in a hybrid 4xBA 1xDD configuration. Many earphones aim to represent bass frequencies in a delicate, tastefully subdued fashion.

...this is not one of them.

The Neo5s understand you're a low-frequency fiend who craves bass and the correct amount is always MORE, and they're very happy to give it to you!

Bass is the star of the show here, so you're going to feel all the rumble & punch that forms the backbone of so much modern music that moves your soul.



As was the case with the ISN EST50s I previously reviewed, the Neo5s arrive in a small cardboard box, and inside is a robust leather carry case.

Three sets of eartips are supplied, plus a cleaning tool & shirt clip. The overall package is acceptably minimalist given the Neo5's modest price. The stock cable - an ISN S4 - is a very comfortable 4 wire silver-plated OCC copper cable, in your choice of 4.4mm, 3.5mm or 2.5mm terminations.



The Neo5s feel very similar to the Penon Globes I recently reviewed but are slightly smaller, stick out less and are even more comfortable.

In fact for my ear geometry their fit is as perfect as any hybrid IEM I've tried, owing largely to their small size & very sculpted shape. I may be particularly lucky here, since they happen to fit me almost as well as custom IEMs would and can be kept in my ears for many hours without discomfort.

They're also vented which is vital for relieving pressure build-up. The stock cable is light & flexible, with no microphonics or memory effect. My only minor complaint is the metal nozzles - eartips don't grip them quite as securely as nozzles sculpted from the shells theselves, so my Spinfit W1 tips occasionally dislodge from the nozzles as I'm removing the IEMs from my ears unless they're removed very gently.

Sound Impressions​


The Neo5s deliver a bouncy, energetic L-shaped sound with superb dynamics and epic amounts of bass.

Let's begin with bass because that's definitely what you'll notice first. It is unashamedly elevated far beyond neutral, and despite not being the fastest I've heard is definitely not the slowest - this isn't bass that struggles to catch up with the rest of the music, nor is there any lack of cohesion because one driver is working out of sync with the others.

Instead there's a huge volume of bass quantity that's biased more towards sub rather than midbass, but the rest of the frequency spectrum feels impressively unaffected. You'll occasionally notice a little bit of bleed into the midrange, but ISN have a done an excellent job of preventing the rest of the presentation from being overwhelmed.

In fact rather than sounding like a blunt instrument the Neo5s come across as surprisingly clean, with instruments like acoustic guitars & string instruments portrayed with the sort of delicacy one does not expect from a set of bass cannons. Make no mistake though, the Neo5s are all about the bass - it will grab your attention through sheer volume, at times when other IEMs would encourage you to focus on different instruments. In many ways the Neo5s feel like going on a diet consisting solely of chocolate cake - the lurking sensation guilt only seems to amplify my enjoyment.


The Neo5 midrange hasn't been forgotten, and is quite forward and resolving considering only 4 BAs and no ESTs are present, and indeed I seldom listen to them with the feeling additional detail is required. That said, midrange instruments can feel a tad small and a modest amount of grain is present. This helps create a feeling of rawness I quite enjoy, but may bother you if you'd prefer to prioritise refinement.

Treble lies somewhere in the goldilocks range for my taste, being neither annoyingly forward or so recessed that details are being obscured. I would say the Neo5s lean somewhat dark, with more upper midrange being needed if you prefer a brighter presentation - something perhaps achievable by swapping to a pure silver cable.

Though treble is resolving enough and won't cause fatigue, I do at times miss the added sparkle & effortless silkiness provided by EST drivers, an area the Neo5s have compromised to maintain their small shells & modest price.

Technical Performance​


The Neo5 soundstage is impressively wide for such a modestly-priced IEM with a low driver count, and I suspect that's largely thanks to its' silver-plated stock cable which excels in this regard. Unfortunately stage depth is not up to the same level, though there's enough depth that the horrible feeling of a ruler-flat stage many cheaper IEMs portray is thankfully absent.

Dynamics are superb, which is a real strength of the Neo5s - this is a quality I value extremely highly, and though they can usually be improved by swapping to a beefier cable it's always nice to start with impressive baseline performance as is the case here.

Other technicalities are about what you'd expect from an IEM in this price range, neither dramatically impressive nor unimpressive. Resolution is quite decent without being outstanding, imaging & separation are fairly average and in general I find the Neo5's technical chops rarely call attention to themselves, but aren't so deficient that they prevent me enjoying the music either.

IEM Comparisons​


So how do the Neo5s stack up against the competition? I compared them with several IEMs on hand… and then even more at Addicted to Audio! All comparisons were made using the Astell & Kern SR35 I recently reviewed, set to Hi-Gain mode with the Neo5s requiring a volume level of 40.

Penon Globe - 2xBA, 1xDD (USD $329)


Physically the Globes are slightly larger & stick out a bit further. I find the Neo5s slightly more comfortable but the Globes are still exceptionally good. Requiring a volume of 38 on the SR35 (vs 40 for the Neo5s) the Globes are similarly easy to drive.

Immediately noticeable is the Globes possessing MUCH lower bass quantity, and bass texture isn't as satisfying either. I'd describe the Globes' bass as merely adequate, whereas the Neo5s emphasise bass enormously. On the other hand the Globes have a blacker background with slightly improved imaging, and a slightly deeper soundstage though it is definitely narrower than the Neo5s'.

Coherency is a great strength of the Globes and they edge the Neo5s in this regard. Tonally the Globes don't feel as dynamic or energetic, instead coming across as smoother with a midrange that feels more emphasised with extra presence and more warmth. The Neo5s have a slight edge in resolution but the difference is slight.

ISN EST50 – 2xBA, 1xDD, 2xEST (USD $449)


Physically larger but similarly sculpted to one's ear geometry, the EST50s' comfort lags slightly behind the Neo5s but their extra bulk helps them isolate a bit more effectively. Requiring a volume of 40 on the SR35 they're just as easy to drive.

Both IEMs clearly share the same DNA with the EST50s delivering similarly elevated levels of bass, and though bass quantity is slightly higher on the Neo5s, I do prefer the EST50s' bass texture. The EST50s are more V-shaped as opposed to the Neo5s' L-shape, so as you'd expect they're appreciably brighter.

Thanks to their EST drivers the EST50s' treble is also silkier & more resolving, helping them feel more refined and less raw. The EST50s' soundstage is also wider, with better imaging & separation, and note weight also feels superior.

Which may point to the EST50s being a straight upgrade to the Neo5s, and in many respects they are, but things aren't quite so simple. Indeed I do think the EST50s offer a superior implementation of their respective tuning, but I prefer the Neo5s' tuning more. Listening to the EST50s however does make me wish the Neo5s had a couple of EST drivers.

Unique Melody Mest MKIII - 4xBA, 1xDD, 1xBCD (USD $2359)


Mest MKIII occupy a completely different price category, but since I'm participating in the Australian tour organised by Damz87 the chance to compare them has presented itself. The MKIII shells are large & stick out quite a lot, and although comfort is reasonable, for multi-hour listening sessions I'd prefer something slightly smaller. The MKIII stock cable is also one of the least ergonomic I've encountered, being incredibly stiff & inflexible. Requiring 48 on the SR35 they benefit from a decent amount of power.

Mest MKIII feel like an even more refined EST50, with a similarly bright V-shaped signature. Bass has terrific texture but substantially lower quantity than the Neo5s', yet is north of neutral enough to feel satisfying. The midrange is MKIII's biggest weakness, being fairly recessed & distant and lacking in lower midrange richness. I'd be reluctant to purchase MEST MKIII on these grounds given a forward midrange with lots of presence is something I value highly.

MEST MKIII's EST-fueled treble is terrific, and is much more prominent than that of the darker Neo5s. Even more impressive are MKIII's technicalities thanks to its' trump card - the bone conduction driver. Being able to localise individual instruments in space so effortlessly & precisely is unquestionably MKIII's standout attribute, aided by terrific soundstage depth & background blackness.

Tonally MEST MKIII lies on the cooler side of the spectrum and its' presentation can feel very "hi-fi" at times, with a lack of warm earthiness hindering its' ability to portray instruments in a believable fashion. This is where I prefer the Neo5 tuning, though the former is unquestionably playing in a different league when it comes to technical performance.

I compared the Neo5's with even more IEMs at Addicted to Audio in Melbourne. My new Astell & Kern SR35 was used for comparisons and for reference the Neo5s require a volume level of 40. Do bear in mind the SR35's 4.4mm jack is more powerful, so IEMs using 3.5mm cables need more volume.

Letshoer s12 Pro - 1xPlanar (USD $169)


The s12 Pros' metal shells are extremely light & comfortable, and with their 3.5mm cable requiring a staggering 70 volume on the SR35 it's clear they require a lot of power to shine! Immediately obvious is how much lower bass quantity is than the Neo5s, but texture is decent despite being on leaner side.

I do find their treble rather wispy and ethereal which isn't quite to my taste, but dynamics are very impressive and resolution & imaging are also terrific. The s12 Pros deliver a much cleaner, more detailed sound but lack the Neo5's visceral punch. They represent surprisingly good value.

Dunu Falcon Ultra - 1xDD (USD $239)


The metal Falcon Ultra shells are tiny and extremely comfortable, and require the same volume of 40 so they're as easy to drive as the Neo5s. Falcon Ultra bass skews towards sub rather than midbass, features impressive bass texture and a satisfying amount of quantity - but still less than the Neo5s.

Falcon Ultra's stage dimensions are similar to Neo5's, dynamics are weaker with a less-punchy presentation and a slightly less prominent midrange, though the Falcon Ultras feel a little warmer. I prefer the Neo5s tonality but am very impressed by the Falcon Ultras which are superb value.

Dunu Vulcan DK-X6 - 2xDD, 4xBA (USD $379)


The Dunu Vulcan's 3.5mm cable requires a volume of 60, and their smooth metal shells are on the slightly large side.

Unfortunately they're a little shouty with upper midrange being a bit of a problem. Treble is somewhat recessed, resolution feels a trifle one-note and even the midrange demonstrates a hint of hollowness. Conversely, soundstage depth is fairly impressive and there's quite a bit of sub bass rumble though bass is less emphasised than on the Neo5s.

Campfire Audio Ponderosa Universal - 5xBA (USD $799)


Ponderosas' bright green shells are large and stick out quite a bit, but I find them snug & comfortable. On their 3.5mm cable Ponderosas require 60 volume on the SR35 so they're fairly hard to drive.

I find Ponderosas have a warm tonality, with more mid bass than sub, but the midrange feels somewhat recessed. They have a fairly relaxed tuning, soundstage depth is quite good and resolution is impressive.

All things considered the Ponderosas don't impress me greatly, compared with the Neo5s which are much more punchy, dynamic & energetic which suits my taste a little better.

Campfire Audio 2023 Supermoon Universal - 1xPlanar (USD $1099)

The bright orange 2023 Supermoons are tuned slightly differently to their predecessors which were only available in custom configuration - it's nice to see CFA adding the universal option.

Their 3.5mm cable requires a volume of just 33 so they're super easy to drive, and their shells feel identical to the Ponderosas. With just one driver their tremendous cohesiveness jumps right out immediately, so if that's a quality you value highly I'd recommend auditioning the Supermoons!

In fact I'd go so far as to say the 2023 Supermoons are possibly the most technically proficient single-driver IEMs I've heard, challenging the Final A8000s & Softears Turii Ti but priced lower than either. Soundstage dimensions are very impressive for a single driver, and resolution is similarly terrific.

I do find Supermoon sub bass a touch weak, treble is fine but again not as prominent as I'd prefer. As with every other single-driver IEM I've heard there's also a slight 'hollowness' to the sound as if the entire frequency spectrum isn't being quite as effortlessly covered as it might be by a multi-driver hybrid.

Thieaudio Monarch MKIII - 2xDD, 6xBA, 2xEST (USD $999)


With their 3.5mm cable requiring a volume of 66, the MKIIIs do require a fair bit of juice. Their shells are fairly large & smooth and comfort is reasonable. Immediately I notice that Thieaudio have 'woken up' the MKIIIs slightly, which are no longer quite as flatly-tuned as the MKIIs.

They still have the same smooth Monarch sound we're used to, pushing impressive amounts of effortless detail towards you in a fairly inoffensive fashion with a soundstage that's very wide but not terribly deep, and they're also bassier than the MKIIs with a less flabby DD being used.

I consider the MKIIIs solid value if you want an earphone that mimicks the refinement of flagship IEMs but you can't quite afford one, yet they're a different animal to the Neo5s which are more dynamic & visceral with far more bass quantity, but lack the same refinement, resolution & stage width.

Campfire Audio Trifecta - 3xDD (USD $3375)


Let's cover the good news first. The Trifecta shells are oddly shaped but actually fairly comfortable despite sticking out quite far, and requiring just 40 volume from a 3.5mm cable they're easy to drive. Trifecta's soundstage is massive, extremely wide and with great depth. They also deliver a similarly visceral bass experience to the Neo5s, with even more bass quantity - the only IEM compared that does.

Trifecta also feels cohesive, largely because it projects a gigantic wall of sound. Unfortunately its' three drivers are horrendously slow, utterly failing miserably to keep up with music of any significant pace. Dynamics are also poor, and at the lower volumes I listen at treble seems nearly non-existent. Everything feels bloated & slow, though some may perhaps find the presentation non-fatiguing. Ultimately I much prefer Neo5's superior dynamics, far more prominent treble, deeper sub bass and cleaner sound.

I joked with one of the Addicted to Audio staffers and he agreed, that if FiR Xenon 6 sounds like being inside a nightclub, Trifecta sounds like being outside a nightclub... on the other side of a brick wall.

Cable Comparisons​


As a confessed cable collector I had to learn how the Neo5s scale with fancier cables, but was surprised how well the stock cable performs.

ISN S4 Stock Cable - (USD $55)

The stock S4 has been very well-chosen. It provides a dramatic amount of sub bass emphasis to create a very 'fat' sound, which enhances the Neo5s' bouncy nature even more. I'm also surprised how much warmth this cable adds despite being silver-plated.

The S4 creates a very mid-forward sound with terrific dynamics, and keeps treble in check without feeling veiled. Trebleheads may long for more upper-treble however.

ISN S8 (USD $32.50)

I've read the S8 was once the Neo5s' stock cable before a change was made, and though this cable sounds quite similar to the S4 I definitely prefer this pairing less.

The S8 makes bass feel more rounded but less impactful with less sub bass emphasis, the soundstage seems narrower & dynamics are inferior. The presentation feels smoother which could be useful if you find the Neo5s too raw on the stock cable, but I prefer the S4 pairing.

Penon Vocal (USD $69)

As expected the Vocal places more emphasis on the midrange, giving it greater volume & smoothness which creates a feeling of increased refinement.

Soundstage depth is slightly improved but width is similar to that of the stock cable, and although bass feels a little tighter overall bass quantity is diminished. I'm indifferent to this pairing as it robs the Neo5s of too much of their dynamics & rawness that I enjoy.

Penon Obsidian (USD $149)

The Obsidian is a modular cable, with both Rhodium and Purple Copper plugs available so you can change its' presentation.

With the Rhodium Plug the Obsidian is brighter than the stock cable with a slightly wider & deeper stage, and added midbass but diminished sub bass. Vocals are pushed forward but the background doesn't feel as black as stock, and I don't care for how the extra brightness influences tonality.

To my ears the Purple Copper plug is a better Neo5 match. Now sub bass is deepened with more slam, the stage is wider than stock, but the Rhodium plug's extra brightness has been replaced by added warmth. The Rhodium plug sounds cleaner with slightly better imaging & marginally increased dynamics -the better option if you prioritise technical performance- but tonality is much better on the Purple Copper plug whereas Rhodium would be better for 'thinning out' an excessively warm IEM. I find the difference between plugs slightly less than the difference between cables.

Effect Audio Ares S 4 Wire (USD $179)

Ares S widens & flattens the stage, sharpens imaging & makes bass feel tighter but lowers perception of subass by shifting emphasis towards midbass.

Likewise the midrange emphasis shifts more to the upper midrange, and treble feels more prominent now. Tonally the character has shifted to a more 'hi-fi' presentation which thins out too much of what I like about the Neo5s on the stock cable.

Hakugei Sky-bolt (USD $884)

This is a heavy behemoth cable with performance to match. Sky-bolt emphasises midbass at the cost of some sub bass which is not a change I prefer, but dynamics are improved, as is background blackness, and the soundstage expands significantly in all directions.

Resolution increases far more than I would've thought possible by swapping cables, and is delivered more effortlessly - almost as though a couple of EST drivers were added. The Neo5s are far more refined & technically capable on the Sky-bolt, though some of the excitement & rawness of the stock cable is absent. The overall change is profound, completely flying in the face of naive cable skeptics.

PW Audio 1950s clone (USD $2149)

This 4 wire Cardas Clear is a clone of PWA's 1950s, and offers superior dynamics, a blacker background, and a much deeper stage though width is increased only marginally.

The midrange feels even more forward, and vocals sound smoother & richer with less grain. Note weight is also improved but sub bass is slightly less emphasised. Once again Cardas Clear delivers another great pairing, though Sky-bolt is another step-up again in technical performance.



It's an audio reviewer's job not only to describe the way things sound, but to articulate his or her feelings towards the subject of the review to explain why they like or dislike it.

I've failed this test miserably - though I really enjoy the Neo5s, I'm struggling to explain why.

Many IEMs cross my desk I'm grudgingly forced to listen to. The Neo5s have been in my ears every day in the weeks since they arrived, and will still be in my ears tomorrow after this review is completed.

Does this make me a basshead... and if I am, does that mean I've been living a lie all these years by telling everyone I love treble?? That's the problem with elevated levels of bass - it's damn addictive, and skews your bass expectations way beyond "normal".

Seriously, the Neo5s are better than they have any right to be. To my ears they sound 'just right', and probably have the perfect mix of frequencies to cancel out whatever wonkiness my ear canals impart on the signal. You may not like them quite as much, but if bass is your thing... try them.
Really enjoyed reading this.
Thank you for the informative review!!
What a great read - thanks for analyzing & comparing all these contenders.
Hello! I'll need something like that. I have a Hiby R3II DAP paired with a Letshuoer S12 Pro. My listening is neutral, no EQ, no MSEB, and I feel that the bass is few and dark. Maybe these NEO5 are the upgrade I need? Thank you so much. Excellent review. Beyond the emotional...


Headphoneus Supremus
Pros: -master of tone and timbre
-chunky rumbly vibrant bass
-balanced basshead L shape with fowards mids
-full bodied male and female vocal
-dense holographic thick sound layering
-wide and tall soundstage
-dark but not dull sounding
-good cable quality
Cons: -slow bass that can struggle to keep pace in busy passage
-contrabass sound off and can go muddy
-not very competitive technicalities
-lack of air and sparkle

TONALITY: 8.5/10


ISN audio is a well established IEMs and cables company that specialize in hybrid earphones offering like ISN H30 or the H40 i review very positively lately.

Today I will review their latest offering, the Neo 5.

Priced 280$, the Neo5 is an hybrid IEM using 1x 10mm dynamic drivers and 4 knowles balanced armature.

Let see in this review how it sound and if the technical performance is above average for the asking price.



The constructionis made of resin plastic and a metal nozzle. The plastic feel sturdy but not very thick. It's soft and light.
The shell isn't very big and have an organic shape that is very comfortable, it's the type of IEM you can forget you wear.
The 2pin connector is on top of body, its not recessed and i find it sometime hard to precisely fit the fact, i even bent some cable pin so be cautious to be sure the direction is perfectly straight when you push it.


I don't encounter any driver flex, this is surely due to well made side venting hole that even have a mesh to avoid dust enterting the shell (something i wish to see with all venting hole in fact). The purple color is very appealing for they eye and very welcome, as well its transparent so you can admire the wire and drivers in the shell. All in all, its not a mind blowing construction or design, but very good still.


For the cable, you have 2 model choice: S4 or S8. Both are ''single crystal copper silver plated'' braided cable. While the S8 is good and have 8 strands, it have less cores by strand for a total of 152 cores while the S4 have a total of 252 cores with it's 4 strands.
I get both but prefer the S4 sound transmission wise. It tend to make spatiality a bit more open, dynamic more controled and treble cleaner. Very good pairing. and worthy of extra 10$ since S4 sell for 60$.


In term of packaging, we have the classic metallic blue box of ISN, which is always appealing for they eyes and unique in its presentation.
The accessories are minimal but wise. As said, you get either S4 or S8 cable (2.5mm, 3.5mm or 4.4mm) which are excellent. Then this false leather carrying case is nice, though im use to bigger one now. Then you have 3 eartips models for a total of 9. Its all silicone and wide bore. Some of those eartips are similar to KBear KB07 and its the one i use the most. As well, you have a cleaning brush and metal cable clamp. All in all, very satisfy with the quality of accessories.



The Neo5 offers a smooth bassy musicality, round as a whole and rich in layers of sound.
It's warm and colorful, here the creamy tonality favors the diversity of the colors of tones and the corporeality of the presence and the timbre before the sharpness of the resolution which is anything but analytical.

This tonal balance is bassy and L-shaped where the fleshy and juicy lows dominate the spectrum and act as a binder for the macrophonic ensemble.
The Neo5 delivers a voluptuous sound, all in rounded curves and without peak, where the bass and midrange form a couple put forward and the treble is tenuous but full of contrast.

It's a full, warm sound, but that warmth is in the timbre of each driver it seem, as if the cutting angles of definition are softened and creamy, delivering a natural-toned, smooth, bodily in presence musicality with no glitch or peaky boost of texture.


The bass is thick and heavy with impact, deliver a round slam and vibrant rumble, with fast sustain and also stocky, without intrusive resonance, it's tactile and striking as desired.
As well, it's colored in warmth and the separation is not amplified in space (or dip) due to a syrupy transition in the low mids.
This bass shift can darken the definition of acoustic kick drum, or magnify its bulk, amplifying its dynamic physicality at the expense of its clarity of presence and clean separation.

The double bass is affected in its technicality, the articulation of this bass line being felted, little textured and contracted in its resonance which forms a dense and weighted mass of air not extending linearly until 20hz, but rather exploding its amplitude of release of the strings.
In other words, it booms and the instrument seems to have the strings hit rather than pulled.

For the cello, this treatment is beneficial to it and completes its fullness of body with a coloring of its fundamental notes boosting a vibrant and natural warmth, hiding the roughness of the texture grain of the bow sliding and projecting its presence even more forward as if the listener was two feet from the instrument.
The rendering is very tactile, luxurious and opulent and very pleasing for lovers of this instrument.

Yes, the Neo5 can be considered ''basshead'', it's more quantitative than performative, the attack speed is not the fastest nor the most controlled, but the dynamics are alive, heavy with impact and wide in presence .
If the jazz is slow, it's okay, but if it's fast and the bass is excited, it might get a bit muddy at the bottom end. I would say that for the classic chamber it is fine, but that the Neo excels with modern music like soul, R&B, rap, Pop for a cleaner and more readable listening.

The mids too are full in bodied and not aggressive in expression of presence, without being recessed or thin, because as I said, the bass warmth complements the macro tone, it doesn't overwhelm it.

This kind of medium magnifies the weight of falling notes and is anything but dry in timbre or light in dynamics.

The vocals are put forward both in presence and in body, it's dense and warm, for both female and male singers, which is a big plus for musical versatility in pop, indie rock, etc.
It seem the Knowles BAs are softened-damped in their projection aggressiveness and filtered in their potential timbral roughness, and so here we don't have to put up with a metallic or shrill timbre, that infamous BA timbre that can make vocals or instruments displeasant sounding.

As for the piano, its tone is full and dense in presence, its strike is heavy and felt, its resonance is contracted, it does not extend into a clean space. Also, the delimitation of these notes is felted, these angles of definition are erased and what dominates is the color of the tone and not the texture and resolution of the notes. So, it can complicate fast passage readability due to this diffuse and abstract note framework in definition.
The violin, though colored with a subtle warmth, is superbly musical, dense, creamy and broad in presence. These bow strokes are not amplified with abrasiveness, the listener will only be less distracted by texture artifacts that are ultimately unattractive to the ears. What I miss is rather the release of the resonance which, like the piano, cuts short and closes in a roundness of elastic presence.

Usually, when an IEM excels in the masculine and feminine register of vocals, it means that we will be spoiled by a full and natural rendering of the saxophone, which is exactly the case with the Neo5, and unlike vocals, the accuracy of understanding the elocution of the lyrics is not as important so I would say that like the cello for its lower end rendering, the saxophone is the favorite instrument of the Neo5.

What bothers me, however, is that moment I listen to ''Zingaro'' by Alexa Tarantino, and despite the fact that her playing is superbly restored, put forward, wide, lush and intimate in presence, dense and velvety in tone, the double bass is a little excited and messy which tend to distracts me because everything flows and intertwines syrupy except this part of the song.

This is very nit picking and not really about the mid range which is a master of tone and timbre, and ultimately: musicality.

Then these high frequencies are a little dark, but energetic in dynamics and realistic, although colored with softening The whole thing is really sweet, perfect for those sensitive to treble.
But I want to note that I received 2 ISN cables, the S8 in the first place tended to cream the treble a little, as for the S4 it adds a little more sharpness and flicker as well as aerial opening, but the highs stay warm and rounded in the corners of definition.

These highs won't distract you with an invasion of shooted sound information, it's ''laid back'' but rich in layers of sound. For the hard of hearing, it will be too dark, but for those with curious ears, there is auditory food to be desired here, although the rendering remains ''impressionistic''.

For example, the percussions are not cut out with precision, they lack a bit of aeration, and the rendering is a bit ''analogue'' and euphonic, the material is more there than the delimitation of texture or an urgency of amplitude . The crash of the cymbals is attenuated and even muffled, so no ''splashyness'' for sure, remains that the cleanliness is not absolute here.

As for the acoustic guitar, it's quite tenuous and even a little remote in presence if played gently like on Jacob bro's ''Gefion'' album, where the double bass is more forward even in the gratement from his attack, Jacob seems really far behind it's mass of sound, but remains noticeable and well defined. If I go for a complex guitar solo, like those of James Blackshaw .... the shoe pinches even more, it's very messy and abstract in the delimitation of note, this lack of cleanliness, of crystalline, of micro definition and precision, the counterpoints are unreadable and too buttery due to the dominant bass harmonics.

Let's say that the high frequencies are not the most glorious in detailed or energy except between the 4khz and 8khz range, which explains the magnificent rendering of the violin, saxophone and even the highest soprano vocals. Harp, harpsichord and even acoustic guitar enthusiasts should abstain because the Neo5 sound is too hot to do them justice.

The spatiality is wide and high, but not very deep due to this thick overall rendering in colored sound layers…it can gain in depth with instrumental music without a dominant bass which congests the space. It acts like a wall of sound surrounding the listener, it's not stuck in the head, it's open but veiled.

So, the sound imagery is average without more, good tactile separation of the layers of sounds which adds up but not very sharp definition of each instrument, nor clean and vast separation between them. Transparency and clarity are not the strong points of the Neo5, nor is precision. Basses and vocals are the easiest to draw.


AT 26ohm of impedance and 111db of sensitivity, the Neo5 are very hard to drive nor very sensitive to output impedance or amping gain. It love clean and slightly bright source to wake up it's resolution capacity, about amping, to get the full dynamic heft i would say 100mW is enough.

Eartips choice is very important, but thank to Penon, they include the right one wich are the wide bore, it permit to open spatial wideness and extended rumble and bass heft as well as mids fullness and presence. With longer silicone eartips, it can compress and brighten the sound, very different sound impressions I would write with such an eartips, surely a negative one.

And as said, the S4 cable is my fav pairing for these Neo5, ive try multiple cable like Hakugei SPC ,Tri Grace S etc, but dynamic wasn't as clean and linear (not dead flat) as S4. So, again: it worth the extra 10$ ivestment I think.



VS RAPTGO HOOK X HBB (1planar+1piezo driver-260$)

The Hook sounds more open, offers a more W-shaped tonal curve where the emphasis is more around the sub-bass and does not offer as heavy, dense and round bass-mid hit as the Neo 5.
Its basses are a little more textured and saturated in grain of presence, the extension is cleaner, less ''boomy'' and in the end, less basshead than the more dynamic and fully boosted basses of the Neo5.
The mids are clearer and more textured in their presence, but flatter in dynamics and less dense in sonic layers. The definition of the instruments has more acidity compared to the Neo5 which are warmer, more colorful and thicker in timbre, offers more frontal and intimate masculine and feminine vocals with a creamier and more natural timbre, has a more massive and aroundie corporeality of presence.
The treble is more aggressive, lively and catchy, the percussion has a sharper definition and a more immediate and abrasive rendering speed, it's more airy too. The Neo5's treble is darker, hazy, thicker and softened, delivering a lower level of readable sound information.
The spatiality is wider and deeper with the Hooks, more closed and intimate with the Neo5s.
Sound imaging is superior in transparency, positioning accuracy, the separation space is wider and cleaner.

In the end, it is obvious that the technical performance of the Raptgo Hook X HBB is superior to all levels except perhaps the dynamic impact weight. On the other hand, tonally the Neo5 offers a more fun and fleshy bass, but above all a more beautiful vocal with a warmer and more natural timbre than the HBB, victim of a planar grain.

VS HIDIZS MS5 (1DD+4BAs-400$)

The MS5 is more U shape in balance, its brighter and treble is more focused delivering a more technical musicality.
The bass hit less hard, is thinner but cleaner and lack mid bass punch and chunk of Neo5 which is warmer, rumblier and more rounded between kick and bass line.
The mids are thinner and brighter with the MS5, but more open and more boosted in presence details and upper mids, so more prompt to sibilance.
The treble is notably more focused and excited, a bit airier too, attack is faster and more edgy so percussions are put notably more fowards in the mix than darker Neo5.
Soundstage is wider and deeper with the MS5, but center stage is more recessed too.
Imaging is clearer and more easy to pin point positioning with the MS5.

All in all, MS5 might feel technicaly superior but tonal balance isn't as cohesive, tone isn't right, its thin and dry, musicality is colder and harsher making it hard to suggest over warmer, bassier and more fun and natural sounding Neo5 costing 120$ less.



While I can't call the Neo5 master of technicalities, it's lush tone and addictive bass and vocal make it very easy to love. This is the kind of IEM that make time pass without we notice it because it's easy to get lost in it's cozzy and dynamic musicality.

It might be a bit of guilty pleasure, but the fact its so well balanced and sirupy as a whole tend to not make me ashame of loving the Neo 5.

These will please both basshead and vocal lover, as well, those who are afraid of balanced armature metallic timbre can be relieve: here it's creamy, euphonic and natural tone, and it doesn't sound thin at all: everything is thick and full in body with the Neo5.

For me, this is a refreshing sounding earphones in the sens lately most chifi goes Harman target or forget about lower mid range, the Neo5 doesn't and it pay off in term of audio enthusiast pleasure.



PS: I want to thanks Penon for sending me this review sample after I manifest my curiosity about them, due to my sincere love of ISN H40. Again, those are my unbiased subjective critical listening impressions and nothing can affect their freedom of thoughs.

You can order the ISN Neo 5 for 280$ here:


Headphoneus Supremus
ISN NEO 5 is trying a new fun sound
Pros: Big lush bass
Vocals forward and euphonic
Mids is forward and thick
Treble detailed and none offensive
Gorgeous design
Ergonomic and small shell
Good accessories
Cable is good for stock cable
Cons: Overpowering bass
Some mid centric music can get to forward and thick
Female vocals on the more airy and bright side sounds off
Some instruments lack that extra realism
Treble is on the darker side
Intimate soundstage



The NEO 5 is the 4th IEM I have owned from ISN Audio, I bought it with a small discount for the review. All impressions are my own subjective thoughts after having used them for a good time, and I have no association with ISN writing this.
This is also a very subjective hobby where everything from experience, anatomy or age will affect what we hear. Also keep in mind that it is easy to use bold words when talking about differences, while it may be perceived as a small change for you. While I can perceive something as natural sounding, I do believe we can never get a perfect performance similar to what is achieved live.


About me and my gear used for the review

My audio preference is neutral with increased low end, mids can be forward but not too much. I can also handle some treble spikes if it is not excessive. I am a believer in having different tuned IEMs for different genres or moods instead of chasing the single perfect one.
Main music genres I listen to are Metal, Electronica, Jazz, Indy rock/metal, R&B, Pop. I am a music lover, and can also listen to almost all the genres out there. I have been into music gear since the mid 90s, gifted some big speakers at an early age. Then moved more and more into headphones with the Koss Porta Pro and a Sony Discman and Minidisc.

I have also tried playing many instruments over the years from piano to sax and have a feel for what's a natural tone, but not the biggest patience in learning to play. My wife has also played many instruments from string to wind instruments and also piano.

My current standard in Headphones is ZMF Verite and Beyerdynamic T1 G2.

My current standard in IEMs is AüR Audio NEOn Pro and Penon Serial. The NEOn Pro has 10 BAs, and has a near perfect tonality for me on the brighter side. The Penon Serial that also has a near perfect tonality for me, that is more euphonic and organic sounding with its triple DD configuration. Both of them have sound signatures that I can listen to all types of music with.
Another set that has shown me how good DD can be in the low end is the AüR Audio Aurora, while not taking over the mids and showing superb natural sound.
In general 3 good sets that set the stage high when I compare other sets.

Gear used in the main rig is Topping E70 DAC together with the Topping A90 Discrete headphone Amp. I also have a Schiit Lokuis I can swap in if I want to do a little analogue EQ.
I have also used the Feliks Audio Echo, one of the more silent OTL amps.

Portable gear used during the review: Penon Tail, Truthear SHIO, Tempotec Sonata HD II , Hiby R6 III, Quidelix 5k.

I have a good range of cables from ISN, DUNU, Penon, NiceHCK, XINHS and Gladiator Cables.


Who is ISN Audio

ISN Audio is a brand under Penon Audio, Penon started in 2013. ISN has a wide range of both cables and IEMs.

When you read around on the forums about ISN, you will notice that people say that ISN is IEMs with a more bass heavy and bright sound signature. While this has some truth, the H30 has a more balanced neutral W shaped sound. And the EST50 is more of L shaped sound with great bass and no offensive upper range. NEO 5

ISN D01 7mm DLC DD
ISN D02 10mm Carbon Chrystal DD
ISN D10 9mm DD
ISN H30 9.2mm Beryllium Frosted DD Bass + 2 BAs mids and highs
ISN H40 9.2mm DD + 1 BAs Mids + 2 BAs Highs
ISN H50 10mm Composite DD + 2BAs Mids + 2BAs Highs
ISN EST50 10mm DD + 1 BA Mids + 1 Highs+ 2 EST Ultra Highs
ISN NEO 5 10mm DD + 4BA

They also have cables from cheaper models to their top model the ISN Solar.


So what is the NEO 5

Taken from the product listing:

ISN Audio NEO 5 4 BA + 1 Dynamic Driver Hybrid 2Pin 0.78mm HiFi Audiophile IEMS


ISN Audio NEO series, different tuning style

Handmade, durable and solid.

Semi-transparent purple shell

Medical grade resin material, light and beautiful, comfortable to wear.

5 drivers hybrid earphone, 10mm diaphragm dynamic driver with 4 Knowles BA hybrid.

HiFi 8 shares single crystal copper silver-plated cable, single share is 19 cores, a total of 8 × 19.


Brand:ISN Audio

Model: NEO 5

Driver: 4 Balanced Armature + 1 Dynamic driver hybrid

2 x Knowles BA for high frequency

2 x Knowles BA fo middle frequency

1 x 10 mm diaphragm dynamic driver for low frequency

Material: resin

Impedance: 26 Ω @1kHz

Sensitivity: 110 ± 3dB @1kHz

Frequency response: 10-20kHz

Connector: 2pin 0.78mm

Cable length: 1.2M


ISN NEO 5 earphone


18 months warranty



First off, what is Timbre?
From the Wikipedia:
The Acoustical Society of America (ASA) Acoustical Terminology definition 12.09 of timbre describes it as "that attribute of auditory sensation which enables a listener to judge that two nonidentical sounds, similarly presented and having the same loudness and pitch, are dissimilar", adding, "Timbre depends primarily upon the frequency spectrum, although it also depends upon the sound pressure and the temporal characteristics of the sound"

First minutes of trying a new set of gear, what I always listen to is how natural and musical it sounds. Much of this goes down to how I perceive the Timbre.

The sound of the NEO 5 is bold with a big low end, mids and treble is refined with no BA timbre. Mids are full and on the thicker side for vocals, while treble is inoffensive. The timbre is not accurate for perfect acoustic playback, but is still a high performer.

Going to use the ranges here in review:


Details and soundstage

Overall resolution is good, it is not too dark or veiled. The part that has the most detail and expression goes to the mid range, even if the bass slightly bleeds into mids. Soundstage is rather intimate, but at same time has very good imaging cues.


Bass is of the slower more mid bass heavy style, very full and euphonic. Sub bass also reaches very low with a great subwoofer like rumble and impact, not the fastest type of bass. So while it slams hard, it does not have the most snappy bounce back. At the same time this type is very fun especially within Hip Hop with sampled bass, also since the amount is also boosted.

The amount of bass is north of what is neutral in the whole bass range, very fun and should delight most bassheads.


Depending on the artist or type of singing the NEO 5 is superb, with loads of detail going to show both low and high mids. It is just that since the mid bass is also boosted it touches the midrange, it adds thickness and takes away some detail.

Female artists on the darker side are good and I like this type of vocal presentation, but when listening to more airy and bright vocals it sounds slightly off.
Affects females much more than males, personally I like a more thick sound on males.

String instruments have great detail and warmth, brass is also very nice without being shouty. Just not the crispest and clear sound, more on the smooth thick style. This goes for most instruments going on in the upper part of the midrange.


Treble is inoffensive without trouble areas making fatigue, and has good enough detail to not sound veiled. For the most part the treble is good, measurements also show great air. But for some reason I don't find the sound very airy, maybe since there is not so forward treble. So even if the air region is boosted it doesn't get the realism right. I find that some instruments lack realism, for example how a cymbal doesn't have the right sparkle and sound blunted. Or have a violin don't have that airy and crisp sound, or how the higher notes on piano seem off.



A small part about what gear I have been enjoying the most with the Aurora.

All my dongles or amps have sounded good with NEO 5, be it based on ESS or CS chips in the DACs. The resolving Penon Tail has been the most resolving and full sounding dongle for Aurora. Going into DAPs and AMPs, the Cayin N7 in Class A does give the NEO 5 more warmth and make it sound clearer with more treble detail over the Penon Tail.

As for tips most of my open bore tips work perfectly, but what I have used the most is Penon own green tips that were in the pack.
Used the stock cable ISN S8 for a long time and works great, but had to test more.
XINHS SPC is the same as Cadmus and White Crane cables, and is an upgrade from S8 with better note weight and resolution.
Then tried to use my Penon Mix, this cable does seem to push the treble more forward and keep low end similar to XINHS.
My Gladiator Cables in copper, delivering great bass and resolution.
Since I find NEO 5 slightly thick and bassy I prefer to go for Penon Mix as it balances the sound.



I will just talk about some of the music I like, the music I use here are some of my reference tracks and also just some I like. When I am listening to music and not evaluating, I prefer to listen to whole albums. When comparing the NEO 5 to other sets I have used the tracks listed here and more. I have some extra focus on music with bass this time, as it's also something the NEO 5 excels at.


Terrace Martin, Robert Glasper, 9th Wonder, Kamasi Washington - From My heart and My Soul

Terrace Martin has some great releases within the jazz or jazz hop genre, this is no exception and is a superb album and track. He has a nice voice and has an old school vibe, like a 90s hip hop sound blended with jazz. The track is very bass heavy with a thicker mid presentation.

The bass with NEO 5 is so big, and really powerful. Don’t care if it slightly steals the show over the vocal, it is so big and can rumble your brain. The bass here is of the slow type in the mix, and rumbles for a long time. NEO 5 is extremely fun with it.

The vocals are also on the darker side and I love this extra fullness, but it's at the cost of getting drowned a little by the bass.


AES DANA - Jetlag Corporation

Vibrant and powerful Electronica, not sure about genre really. Is tagged as IDM, Downtempo, Deep Tech and Progressive Trance. Perfect for checking tonality, bass and treble detail.

First off NEO 5 has bass that is big and bold here, almost too big as it drowns the rest of the mix slightly. This is nitpicking and I find bass close to perfect here. When looking at overall resolution, it's not the best but I think it competes well in its price range. The good thing is that the treble is not too forward aggressive, makes it pleasant for a longer time also at louder volume.


Symbolico - Like Water

I have been into similar music for a long time, a short while ago I discovered Symbolico. Psychedelic electronica or glitch hop, but genre doesn't matter. What matters is how good this guy from Israel is at mixing together everything into something magical.

The beat is addicting, you do get into a trance-like state of mind listening to this. When we talk about heavy hitting bass that will rattle your brain this is that, I do wonder how the sets from Fatfreq or the new Penon Turbo would do. As it already rattles your brain here, so I can not imagine how those are. Bass is huge and slow decaying, same as the AES DANA track this music deserves DD in my book.

I feel that NEO 5 does okay for its resolution here, nothing spectacular but nothing wrong. It is overall a full sound, and I personally find the tonality good for this. Maybe I just could have wished for some more upper energy or less bass.


Emanuel - Need You

Need You is an emotional song, Emanuel has a nice vibe going on here. Touching and with great emotions, the piano accompanying it feels very grounded and pure. The deep heavy bass kick also enhances the emotional vibe.

Emanual has music I love with AüR Audio AURE, and NEO 5 has very similar qualities. It is close but lacks some of the AURE magic.

Piano is on the mellow side but detailed and full, every note has weight to it. And the bass kick is dramatic and big with a slow decay that is very correct in this setting.

His voice is powerful and smooth with throbbing nuances, nothing is muddied up by NEO 5 and I would say the thicker sound of NEO 5 makes this very euphonic.


Veronica Swift - This Bitter Earth

Recently heard this one, great for checking female vocals, piano and violin. Her voice is beautiful, it is touching and emotional. NEO 5 has very good resolution and gives her justice, picking up nuances in both her more slow silent part and the more forward airy part.

Piano sounds overall very real, with just some notes that seem off, lacking something that takes away realism. Violin also has great detail but lacks that little extra that I like.



YOUNHA is a female artist from Korea with a superb voice, together with RM a rapper that is very well known. Mainly going to focus on the voice of both artists here, the instruments are not that forward in the mix.

His voice is very correct and the thicker presentation gives him great fullness, but is also slightly distant. Some of it is due to the recording, so I find it very good overall.
YOUNHA is different sounding than some other sets with a leaner vocal range. When compared to a brighter set IEMs, it will not have the same airiness.
The dynamic range of her voice is shown clearly, and when she is going intense and high it does not get sibilant or tiresome.


The Comet is Coming - Birth of Creation

Nu jazz from London, a group consisting of King Shabaka on sax, Danalogue on keyboard and Betamax on drums. This album is special and has been in my listening rotation since it came out, the track Birth of Creation is one of the best tracks on the album.

Sax is played with finesse and has a mellow and dark sound, almost like a voice singing. The drums gave a nice mix of sparkling cymbals, hits and nice kicks. While the keyboard makes this more of a mix between electronica and jazz, it's a cool track with a story being told.

The NEO 5 does not have the right tonality for me here, I find it too thick. The track is already mellow, and the NEO 5 just enhances it. Sax is a little too veiled for me, lacking ultimate detail and nuance. Cymbal hits lack the sparkle and sound unreal, while the drums are better.
It is not that it sounds bad, but it's not what I prefer for this.


Tzusing - Nature Is Not Created in the Image of Man’s Compassion

Techno or EBM album, not for everyone I admit that.. Some sets can be very tiresome here, I both like this album and use it as a test for fatigue and bass amount. BA bass fails for me here, doesn't matter if its top of the line drivers and implementation.

Just feel that bass on NEO 5, it is big and it holds the pressure under the whole length. The extra sounds are not shouty or tiresome, the metal screech dont kill my ears. The spatial cues are also quite good, and make it feel like you're surrounded by sound.


Black Sabbath - Children of the Grave

Always been a fan of the earlier works from Black Sabbath, this is maybe one of my favourites from Sabbath. Music like this I prefer on more thick sounding sets like the Penon Serial making it all sound fuller.

NEO 5 gives the whole track the fullness and note weight it deserves, similar to how Serial does this. The distorted guitar is great and full, and the bass guitar is also great with authority. The drums are also very well done, with full power and attack. But here also the cymbal is slightly off, it lacks the extra sizzle.
Ozzy has good detail and NEO 5 keeps the edginess of his voice, while being clear and forward.

The ending is really good, spooky almost. The static noise of the recording together with the whispering give a nice ambient feel. And show that the NEO 5 can be quite resolving also.


The Dark Side of the Moon - Double Trouble / Lumos! (Hedwig’s Theme)

The Dark Side of the Moon is very awesome,this is a cool album where they have covers of known songs. Here from Harry Potter with Double trouble, just in a metal version. Rusanda Panfili plays violin both beautifully and vigorously, while Melissa Bonny is great with her voice. All the players are great, superb recording in my opinion and maybe blasphemous for the Harry Potter fans out there.

Going from the Black sabbath track to this is quite different, much cleaner and detailed recording. Drums and guitars sound full with life, violin is clear but lacks some airyness. Melissa also sounds great on the NEO 5. It is a fast track and NEO 5 never feels like it struggles to keep up with the fast parts.


Anathema - A Natural Disaster (Live)

Found this group lately, recommended by a friend from Spain that is also a lover of metal and rock. This is a live recording and sounds very open and big, and the performance is superb to be live. Her voice has lots of detail, with vibrato and big control. His voice is also really nice but she is clearly the one on focus here. Guitars, cello and drums, the whole package is really good.
This track sounds good on almost everything I have, but I do like the extra fullness of NEO 5. Drum kick sounds impactful and correct, cymbals are better here than the tracks before and sound more real. The cello is great and gets a small lift from the NEO 5 warmth, guitars also sound great.

Her vocal is portrayed near perfect, with so much detail and emotion. I find the NEO 5 to be great with females if they are not too bright and airy sounding, very correct here where it just is superb.




Rough estimate of how I place them in a spider chart, some of the values tip up or down to show to show off a difference.


Penon Serial

The Serial is a reference set for me on how dynamic driver IEMs should sound like, very correct in musical playback with its analog warm touch.

Serial uses 3 dynamic drivers. One for bass, mids and treble. It has a natural sound that is more analog warm, speed is also slower due to longer resonating decay. It is very musical and fun, which makes me enjoy music more than just picking it apart. So for $300, it is a unique and special IEM. I believe there is a huge chance you would buy one after demoing the Serial.

Comfort is great on both, but after maybe 30 mins with the Serial, I start to notice it. It has a bump in the shell that is not perfect for me, while NEO 5 has perfect shell design. Both have the same type of nozzle in metal, and also length. The Serial is also much harder to drive than the NEO 5, it also seems to scale more with high end gear. Even using my OTL amp is great on Serial, but sounds off on NEO 5.

Resolution of the Serial has always been good for me, but it has still not been spectacular. Bass range resolution is very similar on both sets, same for the instruments part. Only when listening to more airy instruments does it sound more correct and real on the Serial. Some complain that Serial is dark sounding, don't agree. Maybe on the darker side but it still has some great treble details and air, but power is a thing here. Try and volume match when testing and it's much closer in darkness between NEO 5 and Serial.

Bass is very good on Serial, has a very good balance of sub and mid bass. Bass is slightly on the slower side, NEO 5 has bass that is snappier with a harder edge to it.
Sub bass has great rumble and impact on both, mid bass is also very similar. Mid bass is more elevated on the Serial, this means even more euphonic bass and instrument playing.

Mids seems to me to be slightly too thick in the lowest range on the Serial, similar to the NEO 5. The vocals seem closer in NEO 5 and further out on Serial, this makes it for me so the Serial has a slightly more natural presentation on vocals. Same goes for instruments, it is more organic sounding with the Serial. I am not saying NEO 5 has a bad midrange, but just that Serial is a step up for me. But at the same time NEO 5 has a clearer midrange, which can be better for some music.

Treble can have some blunted edge to it on NEO 5, while I find both to have similar treble detail. It is a tonality difference due to the BA against the Serial DD, the NEO 5 can also seem brighter without actually having more detail.

Stage is larger on Serial and smaller on NEO 5, this also goes for layering of the stage.

Some songs and how they do:

The Bitter Earth has more airiness and sounds more real on the Serial, be it piano or her voice. Resolution is almost the same, but there is something about the Serial not shown in the NEO 5 like how her vocal is doing vibrato. When talking about correct tonality, it is closer to what it sounds like in real life. The Serial has a clear win, there is something unreal about the NEO 5 in comparison.

From My Hearth and My Soul is a good example that actually shows the mid bass is more forward on Serial than NEO 5. It is more pleasant and correct on NEO 5, while also being boosted it stays more in line. The singing is better on Serial but it's shadowed more than on NEO 5, so in the end I prefer NEO 5 more. Only the drum hi hat is better on Serial.

Like Water has a big bass already, and both show a great thick low end. They are actually very similar in how they sound in the bass here. Biggest change here is that NEO 5's tonality is less dark, it's very clear that the BAs give off a cleaner sound.

Tzuing’s Nature track is big and gives some serious rumble on both sets, but is more bass heavy on Serial. How it all decays also seems slower on the Serial and snappier on NEO 5. There is actually more detail in NEO 5 when listening to the spatial cues and metal hammering.



The EST50 is a tribrid that I own and love, it fits quite well in here for a comparison. It is priced higher, but is the top model from ISN. The sound of the EST50 is more L shaped in the sound signature with the sub bass taking the spotlight. Price is $449 and you get 1DD for low end, 1 BA for the mids and 1 for the high frequencies. Also for ultra high frequencies you get 2 EST drivers. Comfort for me is superb on EST50 and due nozzle being longer and in resin instead of metal on the NEO 5, even if NEO 5 is smaller I find EST the best here.

The EST50 is not the most resolving set, but it is not veiled either. And I find it more resolving than NEO 5 on its low end and high end. While the midrange is more detailed with more nuances on NEO 5.

Bass is what impressed me the most with the EST50, it is known for its great low end. Providing textured bass that is boosted and reaching very low, almost like a subwoofer backing up a stereo system. Impactful bass kicks that make you smile, at least if you are a bass lover like me.
Both have impactful sub bass, but the EST50 is the most sub bass focused. NEO 5 may have similar amounts of sub bass, but I find it less detailed. Maybe since the mid bass takes over more of the bass on the NEO 5. For example cello or bass guitar has a thicker tonality and lacks some of the finesse than EST50 have.

Mids is more forward on NEO 5 than EST50, it is also of a higher quality. I guess the BAs on the EST50 show some age compared to the new Knowles in the NEO 5. Female vocals are more smooth with less tendency to be grainy. It is also more forward and thick compared to the EST50. This also goes for male vocals, but at same time darker males can get too thick for my taste and make me prefer the EST50, even if it sounds more refined on NEO 5.
String instruments do show better layering on NEO 5, but if they use the higher strings it also lacks some airiness that EST50 have. But double bass, cello or guitars sound thick and nuanced on NEO 5 and I prefer it better here than EST50 even if it's too thick sounding.

Treble detail is better on EST50 with more sparkle and airiness, some people are calling the EST50 dark. Never thought so myself, but I guess we all hear differently. I find NEO 5 darker than EST50, the more thick low end and mids take away the focus from the treble. Listening to cymbals or percussion, the NEO 5 lack that shimmer that gives realism.

Soundstage is also much more wide and layered on the EST50, going back and forth the NEO 5 is slightly boxed in.

Double Trouble is thicker on the NEO 5 with instruments and her voice being more full and refined. The Violin doesn't sound totally correct and makes me like EST50 more, but I still would pick NEO 5 for this.

WINTER FLOWER is more airy when she goes high on the EST50, while she also can have some grittiness. NEO 5 is less airy but is nicer on her voice, and his voice is also better on NEO5 while a little thick. Prefer the NEO 5 here.

Like Water is fun on both sets, and since it's not the most technical track I can go for both sets with a slight preference for EST50. It just sounds better on the bass part and is more clean in the overall picture.

Jetlag Corporation is for me EST50 everyday, the NEO 5 is darker and lacks the finesse that the EST50 treble has. The bass is even bigger on NEO 5 but at the same time more unrefined. Technical electronica deserve good treble, even if some of the main focus is in the bass.



Why the H30, first of all it is also an ISN. It is a hybrid with 1 DD and 2 BAs priced at $129. I use the H30 almost daily at work and it has a very good midrange and also sub bass reaching to the lowest octaves.

Both have an ergonomic, but the nozzle on the H30 is longer and sounds better with deep insertion. So in the end NEO 5 stays the most comfortable.

Bass is very well extended on H30, it raises almost linearly all the way. The bass is still bigger on NEO 5 as it is boosted more, the decay is faster on H30 by a good amount.

Both have good midrange, the H30 vocals and instruments appear more bright. While the NEO 5 has more euphonic thick midrange, and when listening to vocals it's more detailed going on in NEO 5.

Going up into the upper midrange/ lower treble is where it goes a little down for H30.The H30 has some extra energy around 5-7k Hz, this can be fatiguing for some depending on how sensitive you are to this range. it is not sibilant, the energy is more forward. NEO 5 is more relaxed here in comparison, and if a song has sibilance it is controlled best on NEO 5.

Upper treble is well extended on both, and I find both okay in treble extension. While some shimmer on percussion is more present on H3, in general instruments using the treble have better realistic timbre.

Also a note on soundstage. The H30 is really good for its price, and is larger than NEO 5 with more depth and width.

This Bitter Earth is very clean and detailed on H30, but lacks some soul to it and sounds cold.
NEO 5 has more organic piano, violin and singing.

Need You by Emanual is not as impressive on H30 as NEO 5, it lacks the fullness of his vocal and the piano also is too thin. The clapping more out in the track has a sharp edge to it on H30 that is more pleasant on NEO 5.

Birth of Creation is much more correct and nice on H30, more clear sound. Bass is not taking over too much on the H30, so the instruments can shine more.

Children of the Grave is clear and nuanced on H30, but lacks the extra oomph that NEO 5 gives. Cymbals while having the extra sparkle on H30 are also on the more sharp side.
And I would pick NEO 5 every day over H30 for more old metal music like this.

Jetlag Corporation has more detail going on in H30, but at the same time is slightly too sharp sounding. So I would also pick NEO 5 for this, even if the bass has a faster sound to it I prefer the boosted slower NEO 5 bass here.



I like the ISN NEO 5 very much, it has a fun and euphonic sound. And is one of the best hybrids you can get around the price, especially if you like that Penon style warm low end. It is not the IEM I would use for perfect playback of acoustic music, but more the fun set you have for electronica or Hip Hop.

ISN have full bodied sound with ISN NEO 5, and also have a more full sounding midrange with a more relaxed approach to treble. So a perfect set for those who want an inoffensive sound with great low end, should please more bass heads than the neutral crowd.

It gets a thumbs up for me, even with my cons. If Penon would come with another model in the NEO series I would have loved some changes, EST50 style bass with NEO 5 mids. And get in some ESTs, or other drivers for its treble to sound more natural.

Ranking System

1 Very bad or unlistanable
2 Listenable but not good
3 Average
4 Very good
5 Exceptional or having a special sauce

Price can push something up or down half grade.

Going by this ranking system together with my deeper evaluation matrix, the Neo 5 get a 4 in sound qualities.

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Great review, mate!
Very enjoyable review to read Leo, the Neo Series has my full attention, especially for the Neo 7 and upcoming siblings 😎
Excellent review. Thanks.


Previously known as TheDeafMonk
ISN Neo 5 - A Fantastic Fun Purple Puncher!
Pros: What I Liked:
The Price Point! A clear upgrade to entry level hybrids out there.
The tuning change between the H50 and this Neo5 is very different and shows real talent to pull off a new direction.
The tuning is well executed and offers a cohesive Dynamic Driver & Balanced Armature experience with minimal BA timbre.
Bass is authoritative and still has some good snap and texture while being tilted towards the sub bass side more so than the mid bass.
Slightly warm vocals adds a nice bit of texture to the singers voice in a smooth and organic way. Not thin or veiled sounding at all.
The highs are smooth and give enough energy to add excitement but not too much to make the Neo5 fatiguing and defiantly lets you turn up the volume for long periods of time.
Highs are crips and the quality Knowles BA bring out the cymbal crashes without getting splashy.
Love the fact you can get your choice of cable termination. 3.5 SE, 2.5 Bal and 4.4 Pentaconn
I have to mention the PURPLE SHELL bold and bad ass! Great quality and comfort for my medium sized ears.
Cons: What I Though Needed Improvement:
Not much honestly maybe a bit more upper treble energy to add the missing link for female vocals to make them perfect for me.
Slight bass bleed into female vocals where it slightly lowers them a octave not in too much of a negative way more in a coloured way so people who value tonally perfect uncoloured vocals or a less warmer sound will notice.
Stage more intimate just average not exceptionally 3D even with wide bore tips.
ISN Neo5 A New Affordable Awesome $279


Now let's get into it: The Techy Stuff

5 Driver per side configuration:
1x 10mm Dynamic Driver Composite Diaphragm ( Unknown Composition )
2x Knowles Balanced Armature Mids
2x Knowles Balanced Armature Highs
3 Way Cross Over
26 Ohms Resistance
110 db Sensitivity
Handmade Resin Shell
2 Pin flush Termination.
Cable is 8 Strand Silver Plated Oxygen Free Copper Cable
18 Month Warranty.

I Purchased my Unit with a discount from Penon - Thank You

I Don’t do disclaimers for me it doesn’t need to be said. Strait Goods always from me. If something is bad it gets called out. If its great it gets the praise and a deserved hype!

ISH Neo5 is a fantastic fun purple puncher!

More information can be found here and non-affiliated link:

Subjective Part of my Audio Review -
I share my impressions as I hear them with my ears.

As all our ears are different shapes & size so what I hear as bright or bass heavy -you might hear as dull and Vise-Versa; just something to be mindful of.

What makes my ears happy as a sound signature is a slightly more aggressive L shape. I love my Bass Sub and Mid Bass love it all actually; and in large quantity. With the Bass, I prefer a faster decay the faster the better so as to not bleed into the mids., I am treble sensitive and prefer a slightly darker warmer replay with good treble extension without excessive brightness.

I prefer the fast speedy bass of the Beryllium Coated Driver of my Xenns Mangird UP with a Beryllium Coated Driver and the PENON 10th hits my perfect tonality in bass texture.

Planar bass is out for me as again it lacks sub harmonics and texture I find Dynamic Drivers do better. Same as BA bass the only exception was from the 64 Audio U12t that doesn't sound like a BA Sub.

My music Library is widely varied from; Metallica, Great White, Cowboy Junkies, Pink Floyd, Adelle, Melisa Ethridge, Fleetwood Mac, Five for Fighting, Mänskin, Poncho Sanchez, Jimmy Smith, Chopin, The Crystal Method just to name a few. When not listening to my test tracks the majority is Jazz or Alternative Rock especially Female Rock. Lorde, Halsey, Alanis Morrisette, Evanescence. All depends on my mood.

Sources: E1DA SG3, Shanling UP5, Geshelli JNOG J2 with AKM4493 chip. Truthear SHIO (Dual Cirrus Logic 43198 DAC Chips)

DAP/TRASPORT: From Lenovo Laptop with Qbuz Samsung S22 Ultra with DSD Files.

Amps: LoxjiP20 & XDUOO MT-604 tube hybrid amps and Topping A90D Amp 4.4 Pentagon Balanced Out - Unless stated

I also use a iFi Stack with a ZENCAN and ZENDAC2 for a warmer combo.



My Format has changed with community feedback. So now I will list the music tracks I used & why with my musical impressions of the playback using that track. I hope this will give you some context for my library and give you some contexts to compare using the same tracks.

Let's Begin: Critical listening per track Notes taken NOT OVERALL IMPRESSIONS

#1 "Never Be Me- LIVE" Miley Cyrus - Nice Balance between the bass lines , the vocals , and the highs is perfect for this genre.

#2 "Prayer" Hania Rani - The Low drone bass drops are well presented , piano sounds right, not the lowest sub bass, bass seems to be focused in the lower bass between the sub bass and mid bass region.

#3 "Check It Out" Nicki Minaj Both will I am and Nicki's vocals front and center with big bass nice to hear the Neo5 can tinkle your ear hairs while belting out sweet vocals, I think the Neo5 favors male vocals over female vocals as it sounds like a tad too much energy in female vocals to be perfectly accurate while male vocals sound perfect.

#4 "Rocklandwonderland" Kim Mitchell - Fast snappy Mid Bass attack and enough highs to make rock music truly fun to listen to at volume.

#5 "Queen Of New York City" Matchbox Twenty - Male vocals are so good still lots of bass energy but vocals still not washed out.

#6 "Kashmir: Jimmy Page & Robert Plant - Wishing for a bit more upper energy but vocals and drums sound so good

#7 " Money For Nothing" - Dire Straits this track is great for getting a sense of dynamics - here the Neo5 did a better than average job of the replay enough to make the track exciting but shows its limitations of its tuning and drivers compared to other IEM's like the Penon 10th at almost double the price that’s giving good credit to the Neo5 for what it can achieve at this price point!

#8 "All I Wanna Do Is Make Love To You" by Heart - A good track to listen to female vocals. The Neo5 plays this back so nicely are the Vocals perfect NO, A tad thick I mean just a bit but hard to not sit back and enjoy this track none the less.

#9 "Steel River" by Chris Rea - a classic track to just sit back and enjoy exceptional vocals and the Neo5 makes it quite enjoyable.

#10 " The End" by Kings Of Leon - Can be a more busy track with L+R separation , center vocals and prominent instrumental mix and the Neo5 did it very well and lets you still pick up the details and keeps the vocals very organic.

#11 "You Make Loving Fun" - by Fleetwood Mac on this song you can tell the highs are rolled off but the vocals comes across as fantastic and on even par with the low end.

#12 "Dee" by Ozzy Osbourne - a great presentation lots of note weight but here I was wishing for more resolution and you would need more high frequency energy to make the pulls and slides perfect.

#13 "Nothing Else Matters" another track by Miley Cyrus - Bass hits go low and hits nicely no mid bass bloat could be heard to screw up her vocals!

#14 "Ghost Story" by Sting - Perfect male vocals and nice balance overall.

#15 "Sun King" by The CULT - For me the reason I would pick up this set for a kick ass session for a bout of rock music - The Neo5 goes loud and belts out some serious jams.

Shell Shape is Fantastic Compare Pic VS FAN2


This NEW ISN Neo5 and its new tuning has taken a great direction in its different tuning. Bass lines come off more sub bass focused over Mid bass but still has tons of energy there to make drums and instruments sound impactful and tonally correct.

Vocals and mids using the stock cable are probably designed to give a slightly warmer presentation. I found with eartips and cable rolling I could fine tune the Neo5 closer to me desired perfect. For me that was cable with silver and Gold in the mix and JVC Spiral Dot Eartips

I find the Neo5 Mids to be fairly neutral not forward nor recessed in the mix and on the slightly darker side vs thin and sharp.

Treble here on the Neo5 is fairly relaxed and gives plenty of sparkles but treble heads need not apply. The relaxed treble makes the Neo5 a easy listen and fatigue free listen good for treble sensitive people. Rock , EDM are great genre's to dial up the volume and enjoy a seriously long jamb out session.

Stage is average - decently wide and high a "I want It All" by Queen shows that the Neo5 plays back fairly intimate and center of head. This kind of stage is great for making this IEM a good one to just get absorbed in the music and not transfixed on spatial placement.

Instrument separation, Air, Instrument placement and dynamics takes a bit of a hit with the relaxed upper energy tuning and rolled off highs, a trade off for a more musical organic sound versus a more technical set.


While everyone has different tastes I personally like this new tuning direction from ISN on the Neo5 and will certainly appeal to more people than the more niche tuning of the H50.

If you are at the point of taking a plunge of a better quality hybrid set the Neo5 would be a great choice, unlike a bunch of lower quality sets I just recently reviewed where you can clearly tell the unnamed BA or Custom units clearly has a metallic timbre in the upper end, the BA timbre on the Neo5 is minimal to zero and very well tuned and coherent with the Dynamic Driver for a seamless blending.

If your looking for a more bassy set with a slightly warmer vocal presentation and don’t prioritize technicalities or a perfectly uncolored sound the Neo5 will be for you. I like how the Bass of the Neo5 goes low but doesn’t try to overexert itself and try to push the sub bass into distortion a well controlled driver with good tuning.

I don’t think the Neo5 is a all rounder and will work well for certain genre's that focus on the lower 3/4 of the sound spectrum. Classical even some Jazz might leave some wanting if that’s your preference.

I think we all need a set of IEM's that you can jam out to at higher volumes and let you just get lost in the music, the ISN Neo5 does this very well at a exceptionally good price a easy recommendation to progress your journey deeper into the rabbit hole without killing you budget!

In Comparison:
ISN NEO5.png

I will make a point here with these comparisons, And that is I think the Neo5 is a very capable IEM so much so I am going to compare with a few others I also love like the $600 Xenns Mangird UP and the $499 PENON 10th Anniversary. Both certainly better than the Neo5 but just considering comparing against these other exceptional IEM'S is speaking volumes about how well tuned the Neo5 is and what amazing value it brings into the market in 2023.

Vs - ISN H50:

I said about the H50 in my review-

"The H50 is a easy to listen to IEM, Its not going to blast your eardrums out with its overpowering bass, not will it make you totally focus on the vocals. You wont hear sibilant highs nor will the H50 blast you with ear piercing treble. The H50 just is a unique IEM one that is defiantly worth your consideration."

The tuning difference is quite noticeable and I spent a bunch of time A/B the sets to get my impressions correct.

The H50 has more BA timbre and sharpness than the Neo5 where sometimes the H50 gets close for me on sibilant on certain busy tracks that splashiness was much better controlled on the Neo5 and the BA's sounded closer to a DD presentation, Between the two the Neo5 still sounds like it has more high frequency energy over the H50.
The greater Mid Bass on the H50 added a special sauce for adding in bass texture and reverb effects that the Neo5 doesn’t have. The H50 was very much Mid Bass energy forward and the Neo5 pushes its lower energy to 50-100hz vs 60-300hz on the H50 a different presentation and great but different on both sets.
Bass on the Neo5 sounds quicker
Stage has more 3D and height
Female vocals Neo5 is better
The more energy between 1-3K in noticeable on the set giving vocals a different replay towards more my preference.

Vs - XENNS Mangird UP:
NEO5 VS UP.png

Here's where I found an interesting comparison I really do love the bass of the UP but here I found the Neo 5 very comparable the same kind of things that I loved about the up I found in the Neo 5 and for me that is a huge win I like the speediness, I like the slam, I like the fact that it doesn't distort it high volumes quite a win on a sub $300 IEM
So now there's some differences of course I found the mids and the vocals more forward on the Neo5, but the ups had definitely out of all these I MS that I'm comparing the most natural vocals and the best overall presentation of them.
Now the highs here where the Neo Five was more laid back and rolled off on the XENNS UP you definitely get more sparkle more details instrument separation air and that also played a huge difference in the next part the stage.
When you listen to an IEM and you think it has good stage it probably does but compared to what? and that's the nice thing about doing a side by side comparison and here the difference between them I would honestly say the UP takes it UP two level higher over the Neo 5. It is so much noticeable difference in the stage. The UP is dramatically more 3D it's wider it's higher and has more depth that's not saying the Neo Five is bad it's just saying the UP is that much better and shows why its double the price.

Vs - PENON 10th Anniversary:
NEO5 VS 10TH.png

So let's talk bass on the 10th there is definitely more true sub base as well as a faster mid base hit the depth of the details are noticeable in the base texture as well kind of an interesting comparison between 2-6 millimetre drivers versus 1-10 millimeter driver. The 10th space for me is the Pinnacle of base and my preferences it really hits a sweet spot for me.
Now on the 10th the vocals and the mids are presented more forward it's more of a V shaped signature and female vocals are prodigious on the 10th where they are a little bit laid back and thick on the Neo 5.
So here again on the 10th do you get better dynamics? Absolutely! Do you get an obvious difference to micro and macro dynamics? Oh yes absolutely you do! & that's why you would pay extra for the 10th anniversary but what the Neo 5 brings to the table is quite remarkable for its price and must be praised for the execution of its drivers and overall tuning.

Thanks so much, Cheers from the Tone Deaf Monk.



My Video for the ISN Neo 5 is Here:

Discord Server is here for insider information and just good conversation:

My Test Playlist on QuBuz:
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Sorry but I have to - any top-of-your-head comparisons with the Serial?
To be quite honest I didn't find love in the Serial still found it too dark for me and tho some love the bass I couldn't get into its groove. For my taste I really like the Neo5 over the Serial maybe it's the BA mids and highs that sound like DD.


Headphoneus Supremus
The ISN Neo 5 Universal IEM
Pros: Perfect size and shape, taking inspiration from the Penon Globe
Truly a universal custom in every sense of the word
Comes with the 8 share X 19 core silver plated OCC ISN S8 cable
4 Knowles balanced armatures, 2 for treble and 2 for midrange
10mm woofer gets her done
New tuning departure for ISN placing a bump at 6kHz and bass to balance it out
1st tuning of its kind in my experience
Beautiful looking see-though shells
Complete with stainless steel nozzles which hold ear-tips on in place
Balanced, even and correct at any volume used
Full-on authority for modern genres like Rock and IDM
A well formulated and complete treble and midrange
Cons: Strong mid-bass holding bass energy, not your Papa's IEM
Most-likely heavily emulated in the coming months, years
Redcarmoose June 28th, 2023
DSC_0144.jpeg two.jpegqwqw.jpeg

ISN Neo 5
The Neo 5 is a brand new approach to sound design. Showcasing a frequency range placement new to the world of IEMs. Such a development makes a rise 6kHz presence region and instead of a dip. The only way this works is if you have enough low-end to balance it out. Also different from the flagship ISN EST50, they have included a boisterous boost of the 4.6kHz vocal section. In ending this 1DD X 4 Knowles BA invention sounds even, correct and complete despite being new and different. Won’t you join me in the exploration of the exciting ISN Neo 5.

In ten years since Penon/ISN’s start they wowed us with number of IEMs. And while the 5 driver Hybrid which has been named the Neo 5 is not perfect, it’s really moving in that direction. I mean everybody hears differently, but personally I like the Hybrid methodology to building IEMs the best, yep better than Planar and better than full-range single dynamic driver builds. Why? Hybrid technology showcases the intrinsic driver character with-in the persona. Meaning the 10mm dynamic could be considered best at offering big robust bass, with natural fall-off. While the 10mm is not showcasing all the detail found with balanced armature bass, the bass is more dynamic and thorough than other driver philosophies. And laughably, I don’t think it’s ever possible for a balanced armature to procure the levels of bass found with-in the Neo 5? Besides bass, the Neo 5 has 2 extra BAs for treble and 2 for the midrange. Using Knowles drivers we are gifted with what actually sounds a little more cohesive and pleasantly arranged than prior Knowles installments. Now it’s no secret that I personally like Sonion balanced armatures better due to timbre and realness. Except these new Knowles installations have me surprised. Surprised because it’s (maybe) due to the crossovers, or the tuning, or maybe even simply the choice of Knowles drivers, but this is incredibly smooth yet cohesive and real sounding. It’s almost like the steely BA tang of BAs is a thing of the past. You know that tang is a center of research and development, being the number one negative issue with choosing BA playback. While it’s still there, I mean you can tell BAs were used, only there is an even and somehow more natural tone to be found. The positives we get with BAs are still all here. Yep, the separation into the stage, the fast attack and transient abilities, the finite focus of energies into perception of imaging….etc,etc. So somehow Knowles really came through for ISN in this case. But more than that, the Knowles BAs are slightly more forward in use, giving the Neo the name Neo. Yep, it’s a slightly new style of tune for ISN to come-up with. Now we are not trying to hide the BA timbre as it’s needed to be a focus of sound design and placed more forward into the IEM mix of abilities. This in and of itself enables the Neo 5 to offer better vocal rendition, and even come across as a more balanced player, yet still have bass.


DSC_0138.jpeg one.jpeg two.jpeg

Bass is fully achieved having the Neo 5 utilize the low frequency registers of genres like IDM and Rock, you know the genres of music that somehow comes-off incomplete without the needed bass added. Later I will go into the use of both cables, sources with ear-tips to help dial that bass response in. As just the the Neo 5’s older brothers, the ISN EST50 or the Penon Globe, the use of different sources and cables along with ear-tips go to either promote or diminish the bass and it’s effect on clarity and pace.

Taking a philosophical design perspective, the ISN Neo 5 is much in many ways a combination of winning ideas. While most like the Globe, the ISN Neo 5 moves ahead with a stainless steel nozzle like the Fan series. Then absolutely see-through like the ORB, the Neo 5 really takes ideas from past successes.


First row: Penon Globe, Penon ORB and ISN Neo 5
Second row: ISN EST50 and Fan 1

Treble and midrange completeness:

The tuning trick, that ends as departure from previous ISN models centers around seemingly breaking the rules! Yep, this is a new sound and is from a very different tuning to the right way to tune an IEM. While going ahead and matching the 4.6kHz gain identical to the Serial, they then went one step further into the weirdness of a 6kHz bump.............instead of the regular recess.

one .jpeg

1) Now to start with the 4.6kHz lift is still going to sound different than the Serial due to the use of Knowles BAs and not the smaller DD of the Serial. They are taking what’s famous with the 3DD Serial and adding to the ideas.

2) While we find the 6kHz and secondary 7kHz peak of lesser energy than of the 4.6kHz, that is still a departure and I’m going to get to what it does.

Typically the anti-sibilance or presence region of 6kHz has been used to do just that, diminish sibilance. But a tune if structured right this peak actually off-sets the bass energy and creates balance. You need a deep low end, and while we are more of a middle bass emphasis rather than a sub-bass tune, this regular bass is off-set by the clarity the 6kHz bump and (what the) 7kHz bump bring to the table. Now all this talk of bumps may have you believe this tune is somehow pieced together and is a patchwork of sorts? Where nothing could be farther from the truth, here we are met with heavy bass, but the mids and top end are dovetailed together to form the most beautiful example of simplicity. You see this presence region is doing it’s job to actually promote a new style of presence………hence the name Neo 5. It’s a new day for ISN and I feel I really don’t want to compare it to past IEMs………..all except one more. The Globe is very much an inspiration for the Neo 5. Reason being is form, I have said this numerous times before that the extra depth thickness of the Penon Globe, instead of wideness, gives it a unique shape. Such a shape you will note upon first seeing the Globe, as it’s simply different. The Neo 5 takes those form factor ideas and actually improves on them. The Neo 5 is absolutely one of the best fitting IEMs I have ever come across. Now fit is personal, except there are basic values that fit many across the board.

Comparisons to other IEMs:
Such a departure from Penon’s typical house sound, and different from the ISN directions as of recent, there are still subtle remnants leftover of previous ISN joy. Gone are the recessed vocals like the EST50, replaced with added vocal energy. In combination with the added Neo 5 4.6kHz, 6 and 7kHz added V shape resulting from slightly more bass energy. Though due to the Neo 5 highs (in balance) it is very much an end result of prior EST50 bass character, except for the added mid bass. And what is fascinating is how they matched the bass energy of the Serial, and have the exact same 4.6kHz peak too! Yet that is where comparisons to the Serial maybe stop? When it comes down to it there is still a slightly metallic sound to the Neo 5’s BA drivers, which the Serial bypasses using all DDs. Yet this sound, this BA character is so well done, so infinitely (still) smooth, that you could be forgiven for falling in love with the Neo 5’s top-end.



There is a stainless steel nozzle port much like the Penon Fan/Fan2 and ISN H50. The really good thing about the Neo 5 in that this single feature actually is better than the Globes resin nozzle, in that it holds ear-tips on in a more precision fashion. Yep, rejoice my friends in that the nozzle holds tips on in the optimal such a way you even forget to visually check after a while………perfect! This example expresses that we are simply living is the future of IEM production design, overcoming any drawback of the past. The shells offer a semi-transparent medical grade resin, when that is the name, though it is more transparent than semi-transparent. Yep, you can see every detail, every wire, every driver…….plain as day though this lightly toned resin. In many ways reminiscent of the ORB IEM. This form I would call a maximum universal custom form. Such a shape gets its beginnings from the amalgamation of thousands of ear-shapes. And while the very outer ear is indicative of the ears owner, the inside is remarkably universal in shape. Hence our ability to chose a semi-custom shape. I hate to say this as it could lead to (reader apprehension due to the sheer) questionable believability, but this is the one of the best fitting IEM I have ever used.

One of the best fitting IEM I have ever used.

There is a large air vent ringed red of the right and blue for the left, very close to the 2 pin receiver. Probably the optically clear construction is the most noticeable feature of the build, showing no mistakes or sloppy debris upon close inspection. This single feature (to me) shows we have a thoughtful work of art in our hands, hand-made by a master craftsman. And if they pay so close attention to the overall atheistic appearance of the Neo 5, it makes you wonder how much attention was spent on the connections and driver seating, let alone the rest of construction………perfect.

Cable choices:
While Penon/ISN is really first a cable builder (if you study their history) and they included the ISN S8, a $32.50 standard cable on its own.


ISN Audio S8 8 Strands 19 Cores OCC Sliver-plated HiFi Earphone IEM Cable


High purity makes the cable extremely soft, providing the comfort of wearing,
Gold-plated plug is more beautiful and durable, using insulation treatment technology
Natural and transparent sound, delicate and smooth; lift medium and high frequency, strengthen high frequency extension

Brand;ISN Audio
Model: S8
Material: Single Crystal Copper Sliver-plated
Number of cores: 8 shares, single share is 19 cores, a total of 8 × 19.
Connector: MMCX/2pin 0.78mm
Plug:3.5mm audio/2.5mm balanced gold-plug
Cable length: 1.2M

In fact the S8 cable has been included with the ISN H50 and ISN EST50 as a way to get the combination of best sonics and value. Penon has also done the same including the CS819 with a handful of Penon products. The Penon 10th Anniversary Special Edition, the Vortex IEM and the Serial all sport the CS819, and for good reason. Both the ISN S8 and the CS819 go about their business offering a balanced, transparent and all-around basic character. Penon/ISN leaves it up to the consumer if they want to add more character to the signal by rotating in various new cable tones. Different than some manufactures that include just the basic wire with their IEMs, Penon/ISN know cables are important. And even if you don’t believe in cables changing the tone of an IEM, you will defiantly appreciate the ergonomics and overall feel of the included S8 cable. Also if you are just getting started on your IEM journey there is nothing wrong with simply using the S8 cable to enjoy the overall character of the Neo 5. The S8 truly gets the message across with what the Neo 5 is trying to accomplish. And out of completeness here, I’m attempting to interface the ISN Neo 5 with 7 other cable upgrades to learn if a new Neo 5 tone would be more my ticket.


Top to bottom, Penon Leo Plus, Penon OSG, ISN H2, Penon Bass, Penon Vocal, ISN S8, ISN G4, Penon Mix.

It testing the same music was used as well as the Sony WM1Z and identical wide-bore silicone ear-tips. I also spent an extra entire day with a handful of these cables using the more mid centric Sony WM1A. The interesting part was how the ISN Neo 5 responded accordingly regardless of source? Meaning the cable results were closer to the same regardless of source used. So it many ways the ISN Neo 5 is consistent and predictable? Still due to soundstage requirements I used the silicone wide-bore through-out my testing, finding fit more than perfect as well as a more desirable end-tone, holding better bass definition and pace.

Penon Leo Plus Cable:
Deeper blacker backgrounds provide a clear window into slightly wider stage and image size, kind-of like the effects you perceive from louder volumes. The instruments are fuller, rounder and smoother, this goes right along with what the Neo 5 is doing….completely. More accessible than the included cable, more 3D and better separated. Cymbals now take-on a slightly smoother yet more airy form, I know that sounds contradictory, but it’s not.

Penon OSG Cable:
This is the cable I really wanted to try. Yep, number one in enthusiasm, taking the cake of all the others………..and so far it is the very best. I mean it should be costing $299.00? But the way it worked-out was slightly different than what I was expecting. It took and added clarity by far, clear as there was less omnidirectional BA noise. Thus a quieter and more real response, boiling down the essence of tone and offering-up what is true. True being more real, and showing a deeper stage due to a blacker background. Out came tonally correct examples of better timbre. More clear, better seated into the sounding stage, showing a realness that was hard to argue with. Somehow quieter and smoothed out harmonically enhanced.

ISN H2 Cable:
I cheated in the use of this cable. While often in use though-out the week, this was the second most used cable other than the included ISN S8. A more robust sounding offering than the S8. Nice imaging and separation, really clarity for what it is. In case you don’t know the H2 is the ISN lesser costing Hybrid cable, a mixture of silver and copper. Cable material: 6N+ OCC & silver-plated OCC hybrid, at $79.90…..the perfect match-up in this case. A tighter (due to the) silver over a pure copper affair. Separation and imaging into the stage and very well balanced, meaning really this leaves the Neo 5 to almost be what it naturally is, only a clean-up of the deep-end and a faster pace to be found. Such focus on the bass imaging is addictive and of spectacle here, as I can’t get enough of what the H2 is capable of? Clean is my word for the day for the ISN H2! But more than that I’m using the V shaped 4.4mm output of the WM1Z, and there can always be a chance of too much bass or too much treble, yet in all its glory, the H2 is repositioning the sonic elements into a fabulous synergy, creating evenness of playback. I actually don’t ever remember this particular cable being this good? Very very, even?


Penon Bass Cable:
Another cable I’ve spent a few days with, though not that much time. The newest Penon Cable, there is a lot of cable provided for the $99.90.

Here we are offered stage, yep more stage than you would guess? Stage and midrange accentuation into that stage. Big elements and nothing is foggy or not clear. I’m hearing the Bass Cable providing more bass now, which it does just like the name says it does. Somehow the Bass Cable is showcasing what our 10mm DD is up to. That and vocals are one of my favorite attributes of the Bass Cable, an I have been wondering why the vocals are so good here with the Neo 5? It could in fact be from separation, as there is space between the vocals and the music? Bass is tight and not over board like the name (Bass Cable) would have you believe. Think of the Bass Cable as smoothing out the BA character and making a more cohesive rendition of all your instruments, but not offering the blackness of background like the Leo Plus or OSG, but offering a little bit of added blackness. Really it is hard to tell, with the operation at hand? But once again the Bass Cable becomes a favorite here. Also don’t worry adding a cable named Bass to this style of IEM, as it totally works out in the end.

DSC_0057.jpeg top.jpeg

Penon Vocal Cable:
Here is the second to last cable Penon has come-out with. And while I’m now demoing the Vocal Cable with more V shaped WM1Z player, earlier in the week I attempted the blend with the more mid-centric WM1A. Though my take is still the same, yep…..the Vocal Cable is just OK with this set-up? Not the best and not the worst. It really depends on how you are with the intrinsic 4.6kHz peak, that or maybe the 6kHz, as both are more forward than needed to my humble ears. Though I will tell you the stage is amazing as far as spacial displays that go hand and hand with the resulting mids boost! Really not that bad, but not my favorite, but they look great together. This is one of those borderline calls, that I will leave for others to determine the value of. :) But slightly thin sounding?


ISN G4 Cable:
Big, big and full of those things you relish in the perception of stage. Yep, this has been a cable I have used for a few days with the Neo 5 and it still delivers what I originally thought. Graphene is adding a smooth displacement of stage and making the out reaches found like cymbals to become even father outside creating drama. Drama in drums, drama in guitars heck just drama period. Need I say more? One of the best ever with the Neo 5, looks cool together too! But I will add, here we are met with lesser midrange energy than the Vocal Cable, witnessing a style of smooth yet fully actualized playback with big bright instruments, though without any of that brittleness that came with the Vocal Cable. Remember the Vocal Cable has other uses, it’s just the Neo 5 is not one of them. Let me put it another way…….the G4 and Neo 5 were made for one another!

Penon Mix Cable:

Really I don’t know what to expect here? The pure silver is adding a great lift, lifting the high pitched splashes to become just that, splashes. And while clear, I don’t think this is going to be the best match, except for the real treble head amongst us.


Tune similarity:
In all of my interfaces with different IEMs I have only heard this tune one time before.

Now while the Shozy TWS AVA is darker showing less involvement (no 4.6kHz peak or 7kHz peak) though the 6kHz peak is there just like the Neo 5. Also the bass is also added as a necessity for this style of tune to work. And it just so happens the AVA is my favorite TWS IEM being used at the GYM 4 days a week. This tune is unusual but at the same time I see it as the first of many. I purposely didn’t look at the Neo 5 frequency graph before listening as if you really take note, the frequency graph will create massive expectation bias to occur, possibly causing for you to not hear the IEM fairly. After hearing the IEM it reminded me of the AVA and sure enough, the tell-tale boost in the 6kHz was the culprit. I don’t expect you to view the IEM as well balanced, as any new thing is first viewed with skepticism. Yet in the three weeks since it was out, the ISN Neo 5 has garnered grand reviews from listeners, so you don’t have to take my word for it. Read reviews as many are to follow, and makeup your own mind.


Music Examples:

All music was listened to with the ISN S8 included cable, just to be fair. There is a good chance that some of the sound qualities could be improved upon with use of an aftermarket cable.

And Love Said No
44.1 kHz - 16 bit

And Love Said No:
Really the perfect music for the Neo 5. Such deep low-end authority makes this song move. The clarity of BA interpretation of guitar harmonics, and the found separation presented out into the stage. This is why you choose Hybrids over other driver methods.Traversing through my sources I ended up with the Sony WM1Z being the perfect playback with this song. And while there is a slight steeliness to the guitars, I’m actually not sure if that tone is just the recording or BAs aboard, or a combination of both? There really is a crunchy sparkly vibe that shows up as the character known to be occurring in this song. The separation of elements through mixing adds at the opportune time………like the single cymbal crash way out to the right and left at exactly 00:35. This cymbal accent is a reoccurring tool used to (of course) accentuate the groove and rhythm taking place.

Join Me In Death (Razorblade Mix):
The great piano theme, rolling into the guitar presence at 00:16. After 6 days of burn-in, I know the bass is well matured, finding its place in the pocket. There is a looseness here where the most regimented feel comes from the beat at 02:25. Such single bass activities go ahead and show the deepness and style of our low-end, somehow becoming of a physicality that is special. Going back to the start again, there are new found nuances, that come from closer examination. The vocals are placed just right, not too forward or back. I know this album as I purchased the import CD right when it came out in 2004. After playing it for what seems like years and years, the album provides endless vocal harmonies. Most of all here though I’m finding a well done separation of crunchy guitar work that ends up a non-stop fascination along with the glorious vocals.

Heartache Every Moment:
Completely natural going………and going. There is an add to the mix that's really subtle, but there none the less. It’s an additive of rhythm guitar and the Neo 5 gets it, at 00:40 it takes place, it is simply the producers way of adding drama to a simple song structure. When the lead hits it's short but fun at 02:25……….it’s not too bright or lacking luster. That is what I noticed at the very start of hearing the Neo 5, and I still hear it now, where the tune is simply complete, and while not being a vocal forward (specialist) IEM, this is more about everything dove-tailed together. The benefit of hearing the actual guitar chords (harmonics) and bass interactions seemingly complete and hitting home. While there is the slightly bright (probably) 7kHz showcasing the treble technicalities, it comes from a balance with no sibilance found. Such theme in treble goes ahead to add definition to the guitar parts boosted in contrast to the rolling lows.

Album summery:
While not the most imaged-out and expanded version of this playback I’ve heard, it’s not bad. Meaning there is separation, though there is also a trait where the mix has a level of slight confusion to it. Yet when the amazing drama of the stereo mix throws an extra sample of musical adventure outward into an authoritative splendor, all is well. An example would be the imaging of Funeral Of Hearts……… 01:13 the chorus comes in and the song really contains intensity. There is the sound of every one of these 5 drivers coming into play, and while big sounding, it’s not the biggest, though pretty spectacular for $279.00. At least the vocals, guitar and bass sound correct in timbre? I mean if anything this IEM does is dial the timbre in. Drums are not the tightest but follow through offering a unique style of bass focus on this album. The producers have engineered a style of perfect floating bass separation, which is parlayed by the mid bass bump, yet not sloppy really, but well positioned and true to the recording. Really this album contains the perfect example of this style of bass mixing, where it’s not too much or too little, and the Neo 5 gets it, and performs this critical aspect.


The Serenity Of Suffering

44.1 kHz - 16 bit
I have to laugh, as this choice (of music) is again tailor made for the Neo 5. There is a fine line which the Neo 5 walks. Like the story of Goldilocks, where there is a balance of everything, nothing too bright, or too bass laden, while yes, this is a noticeably heavy bass IEM, once you’re acclimated to it, it is not that noticeable. What happens is the bass provides this authority which is critical to music like this. There is also a separation of guitars farther-out into the stage holding itemization which have a crunchy-ness to them. Call this the character of the Neo 5, as it is character, though not off timbre, just the Knowles BAs firing and doing simply what they do day in and day out. The overall effect is that of smoothness inside of what separation is to be found. Here is the song example “Insane” obviously boosted in the lows, boosted by the song and boosted by the Neo 5. To where is found a natural correctness in bass replay, sure there is that slightly loss of pace that comes with a mid-bass boost, but nothing out of the ordinary for music like this. Such emphasis is what is heard when hearing this band live, or simply from a good set of speakers, in that we are receiving the goods from this 10mm DD and they fall into place. The other additive that makes this work is the fact that there is a nice separation always. Now not any style of dislocation, except there is nice room for all sound constituents to be heard and felt. Breaks happen to where you hear new sound elements found holding their timbre and tone................showing-up as a relief against this throbbing back-drop. And I don’t care who you are, you’re not going to find the vocals dark or shouty, as they are in that designer zone, the Neo 5 designer zone. Such a feature is probably one of the curiosities at first......then as you go from album to album trying to cause vocal trouble........when in fact the vocals are amazingly consistent, even though not showy. :)


The Paradigm Shift
Prey For Me:

44.1 kHz -16 bit
Coming in as my all time favorite Korn album. The production never fails to thrill. A fast switch-up in styles which started with the wild fan-base splitting 2011 album, The Path Of Totality. Now really this is a way home for the band, while still not forgetting TPOT. More electronic and more fun though circus synth glides. More drums and more edgy guitar movements, yet the Neo 5 pulls out the magic here. Where you really would have to hear the playback, except it’s all here, really all I would want, and more than I could ask for at this exact price-point. Reason being is the tone and groove found. This is incredibly fast changing music, and the Neo 5 is totally up for the task. At exactly 00:54 the main vocals sing Prey For Me and we are completely on board with the playback. Prior, the lead-up into the song showcased a set of drum accents at 00:28 and somehow the sheer massiveness of the adds takes form. An accent that is really a pre-fire up to what we are going to be introduced to. Like they are starting the album off fluidly, and can do what ever they want, because they are Korn. To rewind to the very first intro, there is a cymbal strike, actually two cymbal strikes right at 00:09 and the Neo 5 nails the tone, fully separated and while not the brightest I’ve ever heard it, it gets the message across, especially fully separated into the stage, like only a good BA can do. Fast attacks and decays here, as what this music calls for. Because of the over-all tone you can choose any volume at will. No worries about stridence or bright heat! To me this is a much better recording than the next album to come out, 2016's The Serenity Of Suffering? Coming out three years earlier, it has remained one of my absolute favorites 10 years running. And what takes the cake here is how the Neo 5 is parlaying both the vocals and those drum accents. All the stuff I’m all about and wanting to hear…………..I selfishly get with this style of replay.


A new unorthodox tuning departure (different) from anything ISN have ever given us. At first gaze upon a looks like one of those crazy attempts at IEM design by the other guys, who are just learning. But upon getting aquatinted with the Neo 5, it is obviously different, but beautifully different. A masterstroke in sound design, the first of many that will arrive this year featuring this experimental tune...........turned hoopla. Yep, hoopla is the only outcome I can fathom taking place? And sure, after one successful mission into sonic surrealism.......there will be the obvious imitators. You know the impostures, the resembling ones made by the copy-cats. Except this tune is no accident,’s a thorough display of IEM understanding and design.

There is nothing like it.

Made into a form which is not too big or too small, the Neo 5 fits into the center of your ear like no other exactly. Easy to drive and well rounded as you can play the Neo 5 simply from a phone, or upgrade to your best equipment and the Neo 5 will show you the ropes. While I selfishly explored Alternative Metal and Love Metal……lol, I had to find my own personal nirvana with the Neo 5. Now that’s not to say you won’t find other genres equally so well done, simply try them! Equal (great) sonics at any volume, and great from a slew of cables and sources, the Neo 5 is sure to generate market disruption and a pack of devoted followers. In fact I gave it the full 5 star score as there is very little fault to be found, unless you’re looking for that old-school linear style of audiophile playback? The sound is big, involving and fun….what else do you want? The thing is ISN didn’t make another IEM just to make another IEM, no……………this here is the fruition of a dream, a dream ISN didn’t even know they had a year ago. A new introduction that shows a new step forward, a step into the right direction, nothing ever stays the same, as there are always new ideas to prove and chances to take. Yet when you’re ISN, there are no mistakes, only innovation, quality and value. And while ISN has never made a bad sounding IEM, there are ones I like a little bit more, than others. Call it finding your sound, or destiny? The Neo 5 is a winner in my book, as it plays just what I want to hear, the way I want to hear it, maybe it will be the same for you too?


Currently Penon/ISN manufactures and sells.

ISN Audio Cable Products:
AG8 Cable
C16 Cable
C2 Cable
C4 Cable
CU4 Cable
G4 Cable
GC4 Cable
GD4 Cable
GS4 Cable
H16 Cable
H2 Cable
H8 Cable
H8Plus Cable
8 Core Cable
S16 Cable
S2 Cable
S4 Cable
S8 Cable
SC4 Cable
Solar Cable
Type C Audio Adapter

ISN Audio IEM Products/Earbud products
Neo 5 IEM

Rambo Earbuds
Rambo II Earbuds

Penon Audio Cable Products
Bass Cable
CS819 Cable
Fiery Cable
Flow Cable
GD848 Cable
HiFi Balanced Adapter
Penon Impact Cable
Leo Cable
Leo Plus Cable
Mix Cable
Neo Cable
Obsidian Cable
Orbit Cable
OS133 Cable
OS133 Adapter
OS849 Cable
OSG Cable
Space Cable
Storm Cable
Totem Cable
Totem Adapter Cable
Totem Adapter Type-C DAC
Vocal Cable

Penon Audio IEM Products
Penon IEM
Impact IEM
Legend IEM
Globe IEM
Serial IEM
Sphere IEM
Volt IEM
Vortex IEM

Penon Tail Dongle
62 individual personal audio products


I want to thank Penon Audio for the love and for the ISN Neo 5 IEM review sample.

These are one persons ideas and concepts, your results may vary.

Equipment Used:
Sony WM1Z Walkman DAP MrWalkman Firmware 4.4mm and 3.5mm
Sony WM1A Walkman DAP MrWalkman Firmware 4.4mm and 3.5mm
Sony TA-ZH1ES DAC/AMP Firmware 1.03
Electra Glide Audio Reference Glide-Reference Standard "Fatboy" Power Cord
Sony Walkman Cradle BCR-NWH10
AudioQuest Carbon USB
PENON AUDIO TAIL Dongle DAC/Amplifier 4.4mm and 3.5mm



Included with your purchase is a shirt clip, a brush, nine pairs of silicone ear-tips and a nice case.
ISN Audio-Neo-5F-700x700.jpg

Photograph courtesy of Penon/ISN Audio

Update: August 10th, 2023
News Flash:

Penon is changing out the S8 included cable with the ISN Neo 5 for the S4. When I did my ISN Neo 5 review I tried all kinds of cables. But.......last night a 2Pin S4 arrived in the mail. Previously I only had MMCX of the S4, and the adapters were only allowing me to add 2Pin to an MMCX plug.

Long story short really there is a big difference to the S4 with the Neo 5. This was something that probably should have been included at the start, but better late than never. Rome wasn't built in a day and everyone is learning at some point. I mean KZ has probably come out with three or four new models of earphones since ISN released the Neo 5 with the S8. Instead of making more and more earphones, they are perfecting what they sell.

While I did try a bunch of cables with the Neo 5, some folks may have less choices right from the get go. Or if they have choices, then possibly they still don't have a cable like the S4. To tell you the truth, the S4 is a enigmatic cable despite its retail price, and despite now being included with the new ISN Neo 5.


So I have a long history of using the S8, in fact it was one of the main cables I used during my ISN EST50 review last year. And while very even and natural, it's really not offering the stage of the S4. Some already know this from experience, of having on hand already the S4 and S8 cables. But to kind of add a little power to this conversation. The S4 opens-up the Neo 5. It makes the Neo 5 live up to its potential as an earphone. Of course if you already have the Neo 5 then there is a good chance it came with the S8 cable. Getting the update is really really important as not only is the stage bigger, but there is more detail inside the imaging. The Neo 5 is actually way more complex than I first gave it credit for. I will be the very first person to tell you that after my review is all finished and posted on Head-Fi, there is still a learning process which takes place as I interface continuously with the IEM in question. Reviews are a liquid thing, even though we look at them as final and offering all there is to know about a particular IEM.

First off the S4 bass with the Neo 5 is more elaborate coming from a slightly more refined area. Such a placement throws out any furry baggage, offering almost a style of simple clarity and positioning that wasn't possible with the S8. I didn't know this in my review? I didn't have the S4 at the time.

The midrange is now expanded into a new stage getting better separation and enhanced involvement. Vocals hold a slightly more forward stance which while the S8 vocals were not bad, it is not arguable that this way is better. Vocals are more upfront and alive, holding more life? Sorry I know of no other way to describe them?

The new S4 treble is simply better elevated. But what comes along with that elevation is harmonics, enhanced areas that were most likely sitting there almost submerged there waiting to be brought into focus.

The total end-results are more clarity and naturalness with added involvement due to such gifts. Quite simply the stage (mainly) is of a different IEM than the S8/Neo 5.


The new Neo 5 with S4 additive!

Last edited:
Yes the Liqueur tips are great, the only ear-tips I have ever experienced where I find fit in two sizes even. They have thick walls that promote a good air-tight fit. But exactly no EQ, and the Neo 5 kinda adds a thickness to where you feel the tones and still has great vocals so you are not missing out there either!
Hello @Redcarmoose,
I noticed that the R & L connectors have a groove on one side and are smooth on the other. Do they have polarity? I have them mounted with the groove facing out. What do you think?

Thank you.👍🏻
Yes, that is super important......:in that is why the groove is there, to showcase the correct polarity in use.