Sennheiser IE 600

Sennheiser IE600 was a groundbreaking release for Sennheiser. They restored their position in the IEM market which Chi-Fi saturated. In 2024, do they still hold the place to challenge other IEMs with a heavy year-long discount? Let’s see

Sennheiser as an IEM Company​

Sennheiser is the most reputed audio brand in the world. But they always struggled with their IEMs. Their mid-tier IE300 was good enough for its time but struggled in the Chi-Fi-dominated market. Their flagship IE900 recently became popular among audiophiles worldwide for its technical capabilities and resolution but was neglected due to the tuning choice they followed.
They always established themselves as the pioneer of Research and Development. Two years ago they introduced the world with their latest 7mm DD-equipped masterstroke named IE600. The market flooded with praises and compliments. But do they hold up in 2024? Let’s see.

Pros​

• It is the most comfortable IEM I have ever tried
• The resolution is excellent
• Technicalities are well-implemented
• The Sub-bass is addictive
• The construction of the shell is very well done

Cons​

• MMCX Connection
• Timber could be a hit-or-miss
• Treble might be too much for some

Burn In is real​

First Audition​

A little story I must tell before starting the review. This is my second review of the IE600, first time I listened to it in 2023-Nov and disliked this IEM tonally, in almost every way. Everything with this IEM felt wrong. I thought it was my psychoacoustics but I listened to it for more than 95 hours and tested it with another reviewer too (Shabtab Quaiser). OnFacebook published a full review from my personal FB account and got backslashed a lot. I always had second thoughts since then.​

Second Audition​

In March 2024 I got to try this IEM once again and my god – it has changed. It jumped from my B- Tier to A+ tier straight. So what happened in the meantime, keeping the source, tips & wire unchanged? Burn In. I get some of you might disagree with the term like me (before the incident).​

So this is the review of Sennheiser IE600 from my perspective​

Dig a little deeper into the tuning methodologies​

IE600 is a very fun IEM to start with. It is tuned having a different tuning philosophy in mind than the Sennheiser IE900. You can watch the interview of Jermo with Doug on the YouTube channel DMS. The first time you put this IEM in your ears, everything would sound very fun, from bass to treble. So throw neutrality out of the window and spectate this IEM as if you are in for fun.


Let’s start the discussion with its timber characteristics. (It is the worst part of this IEM still I would suggest you to not judge it with its timber only).

Timber​

Violin – Sounds transient and very fast. They do miss a little bit of low-end that gives them a fuller body. The upper registers are clear as glass and vividly detailed.

Acoustic Guitar – They sound more digitized than the neutral. They hold the sub-bass in great quantity and the details are excellent but they lack the lifelike feel and you might imagine it as a Contrasting image than a natural one.

Drums – Decay and attack of drums are exceptional. They feel organic and very satisfying in general. They also do not sound very original. Although you will enjoy drums on this IEM a lot just to give it a reference, it sounds less realistic than Softears RSV. Cymbals are very airy and full of details. Trailing edges are exceptionally expressed in this IEM.

Classical Guitar – Classical guitar is not optimal for this IEM, it makes the classical guitar sound body-less and note weights are not well presented.

Cello/Bass – The bass on this IEM sounds very average too. The midrange recession is to blame here. They are full of details but they lack the natural feel too.

Wind Instruments – Wind instruments sound amazing in this IEM. Everything is full of air, full of details and the transient nature is extremely satisfying.

Getting straight to the tonality of this IEM​

Don’t trust graphs alone, without listening first.
Duggu

Click to expand...

Tuning Analysis​

Sub-bass​

The sub-bass of this IEM is extremely good. I am astonished at how they could pull out this performance from a 7mm driver. The attack is full of air, thump is real and authoritative. Attacks are full-bodied and won’t miss a spot in your ambience. In one word the subbass is addictive. I do sometimes EQ the sub-bass 2 / 2.5 db just for extra fun and even then they don’t sweat a bit.

Mid-bass​

The midbass is not as authoritative as the sub-bass but it holds a great body and the fall of the sub-bass never feels unnatural. It was there when needed, and provided the entire spectrum to have a very happy base to play.

Lower Mids ( & Male Voice)​

Lower mids are recessed but they hold the resolution in return. Of course, this is not a mid-focused IEM and you should not expect very much at this price point but even then they do not fail to provide. I am a very mid-centric listener and even then it was not bothersome to me.

Upper Mids ( & Female Vocals)​

Upper mids are very forward in a good way. Anything that occupies the range produced the instrument with excellent resolvability and forwardness. Upper mids flowed like a liquid without giving any harshness to my ears.

Treble​

The treble of this IEM is the showstopper again. Full with resolution and details. Airy as an open field. The extension is excellent for the price. Not only did it give a shining and glittering effect to sound but it held the trailing edges of instruments for decades. Everything was fluid like liquid and effortless handling of the post 10Khz range kept me in awe.

Cable Rolling​

Effect Audio Eros S Cable​

With this cable, Midbass got a boost, which made the mid-range more recessed. But the overall low-end got fuller and more authority is there. Midrange texture improved but they became somewhat pushed back a bit.

The metallic and sizzling feeling that came with this IEM somewhat vanished. It became more organic. The soundstage although got a massive ~15-20% increment.

Everything sounds so cohesive. But mid-range took a backseat tonally.


Now let’s discuss its compatibility with different genres of music.

POP​

This IEM is well suited for Western pop music. The shimmer and shine might be more than enough in some songs but the overall fun element of the genre can be felt in great proportion. This is mainly achievable because of its low-end performance.

Music 1: Loving on Me

Voices are dry and feel over-recessed. Subbass is pure fun. Midbass is very tasteful in proportion. Attack and Slam are on point that it doesn’t bleed into basshead territory. Treble is a bit much for treble-sensitive people.

Music 2: Paint the town red

Highly detailed. Upper registers are sculpted tonally to perfection in this price range. The vocals are very well done & sit perfectly on the mix. Treble is spacious and airy and won’t give you a chance to complain.

Music 3: Death of a Bachelor

Vocals are textured. The upper registers of vocals are very nicely done. Although mids sound a bit recessed. Sizzles and Shines in the whole album is inoffensive and doesn’t overpower the upper mids.

BLUES​

I find this IEM to be extremely good in this genre. The midbass and treble perfectly match the genre. Crispiness is very well provided and the transient nature is a match made in heaven.

Music 1: Do I Move You

Feels spacious enough but not extremely, balanced enough to not feel intimate or huge. I like this Spatial presentation which is a jack of all trades. The treble and resolution are excellent. The vocals lack a bit of texture but feel very natural in the mix.

Music 2: Hummingbird

Feels highly detailed. The bass is just perfect in ambience. Voices are placed beautifully in the mix. Everything in this song feels amazing with this IEM. The treble crispiness showed its ability in a great sense. Everything just snapped, from little cymbal hots to snare drums.

Music 3: Layla Acoustic Live

The same as above. Great attacks and decay, feels tactile and fast. Clean yet it is clinical or inorganic. Treble on this IEM is addictive, to say the least.

ROCK​

This genre might be a hit or miss according to your library. For my library it was average. Never felt that I was missing something but never got the full-bodied feeling that I often look for from this genre.

Music 1: Dreams

The bass is very satisfying, full and thumpy. Voices are very natural in the mix. Spatial elements are very well placed. The acoustic guitar on the left sounds a bit sizzling with a bit of metallic timbre. Again very detailed sounding.

Music 2: Hotel California

Very detailed again. The vocals are slightly recessed but fit well with the mix. Electric guitar misses the time to shine here as the timber is kind of not accurate. Too much treble and less body is there in the guitar. Cymbals are a bit spicy too.

Music 3: Comfortably Numb

Feels spacious enough to enjoy but not too much to lose intimacy. Again very detailed, the nuances are present everywhere. Drums are very well dictated in this song. Midrange texturing is well done too. The guitar solo was excellent too. Atmospheric, had a body, full of details.

HIP-HOP​

For Hip-Hop this IEM is excellent, the sub-bass in this IEM makes the genre so much more enjoyable that 70% of the time after review, I only listen to this genre. The details and resolution capabilities of this IEM greatly go hand in hand with this genre too. Vocals are a very nicely placed mix.

WESTERN ORCHESTRA​

This IEM fits this genre very nicely too. The halls feel spacious and large-sounding. The position of the instruments is very accurately done, and air frequencies are present in a great margin. The resolution of this IEM matches with the textural information in the tracks very well. Every instrument is well-defined and can be isolated from the other ones. For the discounted price of $534 in India, it is hard to find anything that competes with this regarding this genre.

Technicalities​

Soundstage​

Soundtaging on Sennheiser IE600 is a pretty tricky thing to achieve. I am glad to say that this IEM did a very good job of providing a large enough stage and not too large to feel disconnected from the emotion of the songs like the IEM Yanin Aladdin. It is round and projects instruments on the stage very precisely. It is slightly less than or on par with Aful Performer 8 depending on HRTF.

Imaging​

Imaging is very natural for its price. It does not project fake imaging nor it is very precise to a point. The localisation is good enough for the price and will feel very natural and not microscopic. Artists like Amber Rubarth are a joy to listen to on this IEM.

Resolution​

The resolution of this IEM is excellent. It eliminates IEM far beyond its discounted price point in terms of sheer resolution. It is more resolving than something like Aful Performer 8 and on par with something like Monarch MKII.

Drivability​

This IEM scales. And it requires a clean and powerful source to show its potential. It wouldn’t run properly on something like the Abigail Pro dongle. The bare minimum of this IEM is Moondrop Dawn Pro or AFUL Snowy Night. DAPs like Aune M1P matched great with this IEM and Hiby R6 Pro II matched well too.

Conclusion​

I thoroughly enjoyed this IEM even in 2024. And I can recommend this IEM left and right for its discounted price of $530. The sheer amount of fun I had with this Sennheiser IE600 is not something I am ignoring and I am optimistic about the next releases from Sennheiser’s IEM lineup. If you are a neutral listener and trying to break into the fun side of audio, I think it is a perfect entry point for that.


Ratings

Sub Bass – 7.5/10
Bass – 6/10
Lower Mid – 5/10
Upper Mid – 6.5/10
Lower Treble – 6.5/10
Upper Treble – 7.5/10
Timber – 5.5/10
Resolution – 7/10
Imaging – 6.25/10
Soundstage – 6.5/10
Overall Rating – 7.05/10

Tonality = A-

Technicality = A/A+

IE 600​

Here's the second of my reviews of my collection, the quite popular IE 600. I bought my pair at launch in early 2022, for the full MSRP of $800, as a more comfortable alternative to the IER-Z1R that I daily drove at the time. While comfort was certainly a massive improvement, there were a few significant drawbacks. Note that this review was done with the Final Audio E Type tips. While I generally try to use stock tips, that was impossible in this case. No pictures again, cause I need to take better photos.

Build & Comfort​

The actual build portion of the IE 600 is absolutely superb - it's small, comfortable, and clearly built to last. Even the proprietary MMCX was designed with durability in mind, although at massive cost to replaceability. The zirconium alloy shells, being solid, strong, and textured, feel practically indestructible. In the ~1.5 years I've owned my pair, there's not been a single scratch or blemish on them. And while the nozzle is plastic, Sennheiser's history with plastic suggests there is nothing to worry about there.

In isolation, the IE 600 is extremely comfortable being one of the smallest high-end IEMs out there. The shape also lends itself well to setting deep in your ear, without being an overly-deep insertion. The nozzle, while being a little wider than many other IEMs, also doesn't go far enough in to be an issue. The actual isolation isn't incredible though, which leads us into the most serious problem with the IE 600...

A solid 9/10. Would be 10 if the isolation was better.

The Accessories (and related issues)​

The IE 600, with little exception, comes with some of the worst accessories I've ever seen in an IEM. And not just for expensive HiFi, but in general. Seriously, ~$30 earbuds I bought from JLabs 10+ years ago had better accessories. The only thing in recent memory that was equally bad was the BL03, an IEM that goes for 1/20th what I paid for the IE 600. This has been an issue on every Sennheiser IEM I've owned, since the IE 80, and it's sad to see that they've failed miserably to rectify it after all these years.

Now, those are some awfully harsh words, but words I fully intend to back up. Let's start with the ear tips. The IE 600 comes with a nice selection of foam and silicone tips. The foams are a collaboration with Comply, while the silicones are Sennheiser's own in-house design, and both types have a thin filter attached – a nice way to keep earwax/dust out of the IEMs.

This is where the problems begin. The filter, thin as it may seem, is an essential part of the IE 600's tuning and keeps the treble from being piercing and sibilant. Meanwhile, the foam ear tips will blunt the micro details while in typical Comply fashion also degrade in the span of just a month. Never mind how you'll only have 1 pair in your size, and they're not even as comfortable as regular Comply tips.

The silicone tips however, are somehow even worse. It is almost impossible for me (and it seems most other people) to get a consistent seal with them. They're way too thin and thus when squished will collapse instead of filling your ear canal like normal silicone tips. And seeing as how human ear canals aren't perfectly cylindrical, this will consistently happen unless you're extremely careful with the insertion depth. I don’t think I ever once got them to seal perfectly in both ears and actually stay sealed.

The solution might seem obvious - 3rd party ear tips! But this is when that filter comes back to haunt us. Without it, the already spicy treble will be sibilant and piercing on many of the 3rd party tips out there. I've settled on the Final Audio E types, the best of a bunch of poor choices, but your results may vary. Do let me know if you’ve found something that works better than the E Types though, I’m always open to improvements (just not so much paying for the experimentation).

This isn't even mentioning the stock cable(s), which come in 3.5mm and 4.4mm balanced. These cables are absolutely atrocious. They're poorly behaved, prone to tangling, uncomfortable, and even worse, microphonic. The shapable (yet non-removable) ear hooks are a huge part of the problem here. It's difficult enough to shape them properly for your ears, until they change shape the moment you take the IE 600 off or wrap them for storage. The cables and ear hooks will also pull on the shells, breaking the seal on the ear tips.

But it gets even worse. The MMCX connector on the IE 600 is actually proprietary, with an extra lip that means regular MMCX connectors will be too short to make a proper connection. It might be better for durability, but this gave me hell when trying to find 3rd party replacements. It's a little better now that they've been on the market for a while, but most compatible cables will either be more expensive, or you'll need to take your chances with random AliExpress cables.

It's almost like every product Sennheiser makes has to have a proprietary cable or they won't approve it. HD600 2-pin, HD800 janky thing, IE80's weird semi-circle 2 pin, now the IE_00 line and their recessed MMCX connectors.

I find it absolutely mind boggling that Sennheiser, a huge powerhouse in the audio industry, would somehow let an $800 ($1200 if you consider that the IE 900 comes with the same accessories) product leave the lab with such terrible tips and cables. Especially when the tips and fit directly impact the sound so significantly.

The included carrying case is better, being a nice zip up hard shell. It's a little on the small side, however, and would only hold the IE 600 and your choice of USB C dongle. Anything larger and you'd run into difficulty zipping it up and possibly crush a connector. Not terrible, just not ideal.

0/10 - I'd give it a -2/10 if the case wasn't a little useful. It's like nobody even tried to use them before shipping them out.

Anyways, enough griping about the accessories, here's:

Sound Quality​

Overall, the IE 600 is a high performer, with a V-shape sound that extends well into both ends of the frequency response. While it's not my favorite type of sound, the IE 600 does what it does well really well.

Bass​

The bass digs deep into the subbass, with clear impacts and good delineation from the mid-bass and mid-range. There is no bloat or muddiness either. Overall, the IE 600 has very high-quality bass, and is relatively bassy, but keeps away from being warm or laid back. On my standard bass test track, Free Tibet (Vini Vici Remix), the IE 600 truly shows this off. At 1:40, when the bass kicks in, you can clearly feel each individual bass hit and subbass fluctuation. There’s really not much to say here, it’s just really great bass.

10/10

Mids​

The mids however are a little more recessed than I would like, even more so depending on the singer’s voice. Deeper male voices generally sound more natural, although still more pulled back than I’d like, with good rumble and gravel where expected. Brighter voices, especially brighter female vocals, however, show some issues. They tend to be a little hollow on the lower end, due to the mid-range scoop on the IE 600’s FR. On the higher end, the voices will be a little too shrill and piercing at times. Combined, this creates a sense of unevenness in the vocals – you can sometimes hear voices exhibit this as a singer moves up the frequency range.

7/10

Treble​

Finally, the treble is a little too sharp and piercing, depending on the ear tips that you’re using. This is where the horrible stock tips peek their ugly head again – without the filter in the stock tips to pull back the high end, the treble will be unpleasant and piercing especially with wide-bore tips. This combines with the pulled-back mids to make certain voices and instruments sounds hollow and flat or have an icy edge. However, this is also very tip and insertion depth dependent, so your mileage may vary. It’s not all bad though; the IE 600 extends well into the high end and sparkles where expected and prevents anything from sounding lifeless or dull. And despite being piercing at times, the treble is never quite sibilant.

7/10 to 9/10 depending on your sensitivity to treble and the tips you use.

Soundstage and Technicalities​

Perhaps a result of the emphasized treble, the IE 600 is a very detailed and well separated IEM. There’s never any sensation of blurring, muddiness, or losing track of instruments in busy sections of songs. The attack on all parts of the FR is clean and fast, with a clear delineation note to note. Microdetails as well are clear and present.

In a similar vein, the IE 600 also does a great job with instrument separation and positioning. This means that everything is clearly around you in a 3D space and can be picked out just by focusing a little on its location. And while it also manages to create layers of different pieces of the track, the IE 600 doesn’t quite manage to give them depth. Certain things will sound more forward than others, but none of it will quite sound quite distant or spacious. Especially in the central channel where things like vocals can take on an “inside your head” sensation. This is most obvious with female vocals.

The FR also doesn’t lend itself well to natural timbre, although not egregiously unnatural and strange. Instead, vocals may sound a little too grainy, hollow, or sharp depending on their range. For example, on Miwa’s ‘Hikarie – From THE FIRST TAKE’, the singer’s voice sounds almost hoarse or with a sore throat instead of a more natural texture. This holds true for most instruments and voices, although it varies for each; IE 600 is most natural with deep male vocals. This is another aspect that I feel was remedied by the filter in the stock tips. Too bad they’re absolutely unusable.

Again depends on your ear tips. Between a 6/10 and an 8/10.

Conclusion​

As you can see, I’m quite a bit more negative on the IE 600 than many other reviewers here are. However, I feel that once you factor in the atrocious accessories, the IE 600 is only left with its comfort and bass as standout qualities. And those are absolutely incredible strengths that are weighed down by so many issues (most of which are indirect results of the accessories). Perhaps if you can find the perfect 3rd party cable and tips the calculus changes, but I easily went $200 in on accessories before finding a combination that was “good enough” (Hart Audio NK + Final E Types). For my total cost (~$1k USD), there are definitely better options out there that should be considered before the IE 600.

Background and personal preferences

The headphones I love are hd600 and akg k701, esp hd600 with tubes (I use a Cavalli Tube Hybrid). I have owned an LCD 2C, though I loved it a lot I found myself using 600 more. Also had grado sr80 and 225 at some point which followed the same pattern of me moving to 600.

On the good iem side, I have had blon bl03, er2xr and xba N3. I really liked oppoty, and the isolation of etys. But in terms of pure fun, N3 was the clear winner. I am slo an owner of sr846 since last three weeks, which I really really enjoy.

Now that my preferences and experiences are out of the way, here are my impressions on ie600.


Me and ie600 :-

I will be comparing the ie600 with N3 since it has been my daily driver for so lone.

The fit is okay for me. Maybe its the shape of my ears, I don't feel very comfortable with them, they are okay though. The cable is not for me, there is cable noise and I find myself constantly bothered with it touching my neck. Tips aren't perfect for my size either but they are okay. In terms of these experiences, I find N3 much much better. SE846 is the most premium in this regard, I love the cables and fit, and all accessories. They are a more comfortable fit than ie600 for me, and with ety styled 3 flanged tip, they seal so damn good.

I should also mention that I did some tip rolling since that was suggested for reducing treble. I have tried tips from Sony N3 pack, the one from mh755, and some Brainwavz delta tips I had lying around. There wasn't much difference, atleast worth changing to. Anyway, in the end, I think that the sound signature is just not for me. It is not bad, and I would have no problem listening but when there are comparisons to be made, I will go with the rest.

My impressions on the sound (secondary parameters) -

Details are really great, on par with se846. Maybe ie600 delivers more, but it probably comes from the treble extension since se846 lacks there. I find the soundstage pretty decent, but I prefer 846 in this regard. Imaging is good and overall everything sounds crisp.

I can stay its a step up from N3 but diminishing returns, I am more than happy with N3 details and though ie600 is superior, they aren't too much of a step up to N3 in terms of these factors. In terms of 846, I don't call it an upgrade. ie600 is more like a different flavour of sound.

My impressions on the sound (primary parameter) -

By primary parameter, I mean the factor that make me keep the iem. For example, N3 replaced er2xr for me. There was a bit more detail to N3, more bass which surprisingly I loved and overall sound signature of sony which is really fun. N3 did all of this without being fatiguing.

Now, when it comes to ie600, I am not really happy with the signature. The metallic nature of sound (treble sided signature) is off putting at times, also fatiguing. Since my audiophile vocabulary is limited, I will try to explain using some songs I know well and how they sounded on ie600. To put it bluntly, I find 846 more natural and ie600 more treble heavy. In crude terms, for example, the cymbal sounds in background sounds more like 'tttt' in ie600 while in 846 they are more 'dtdtdt'. When it comes to vocals, 846 is more echo-ey and nasal in comparison to ie600. Remember, these are exaggerated expressions for comparison purposes.

I tested all with apple dongle dac. My CTH gave hissing sound to ie600 and 846, not sure if its the amp or iem's sensitivity.

Song testing :


> Ciel errant by Alcest; Storm by GY!BE (non flac file)

In Ciel errant, where the distortion guitar kicks in at around 3' , the song felt artificial. The vocals in background is way too back to the level of being almost inaudible. I had to take the iems out the first time and check if something is wrong with connection. It maybe a case of mids being recessed by bass and treble. With this experience, I tried to 'critically' listen Storm by GY!BE. I was expecting the south Indian wedding pipe music at 4.30' to be muddled similarly since a lot of instruments are at play in background. But it played just fine.

> Ciel errant by Alcest, Storm by GY!BE (flac file)

Ie600 played both fine. I don't know what to take from this. I have had those songs on my phone for so long n I never felt this way while listening with N3. I think, I will just say that ie600 needs better mastered songs to bring out the full potential (?) and are not very forgiving to rest. With this experience, I moved the comparison only to flac files.

> Caspian - Hyms of the greatest generation (flac)

This song starts with a very acoustic sounding strings at the start where you can hear the clanking sound along with main notes. With ie600, it feels like very poor mixing since it elevates the clanking sounds but not with N3 or 846. Thus, one of my favourite song is rendered artificial with ie600 which sucks.

> South London forever - Florence + the machine

With ie600, the 's', 't' etc. in her voice are so damn prominent. With this song, I found the iems quite sibilant. With N3 and 846, this issue was not there.

Conclusions

In general, ie600 is a bit treble heavy for me. I can't use it for longer sessions. There are many times where I find them really nice but they are more one off than universal for my preferences. Also, this is my first time reviewing so do take my views from that perspective.