Symphonium Audio Helios - Official Thread

This is a place to discuss the Helios, a quadruple BA IEM from the brand Symphonium Audio.


Here you can find the review by @Precogvision:

Some additional comments by @taronlissimore:

And some brief first impressions from @antdroid:


@Rush and I just did a livestream podcast on the Symphonium Helios and gave our pros, cons, comparisons and random chit chat about this product.


New YouTube Episode airing tonight at 5PM PST featuring two of the collaborators of the new IEM from Singapore called the Helios from Symphonium Audio and Subtonic.

I’m not in this one, so I’ll be watching it for the first time later. :slight_smile:


The Helios is a new in-ear monitor product from a relatively new brand out of Singapore called Symphonium. The brand started out in 2017 and have three current products in their line-up. The Helios is their flagship product and comes in at about $1099 USD.

The Helios features four balanced armature drivers in a configuration that was developed in collaboration with some familiar faces for those of you who have followed Audio Discourse on YouTube – mainly Leneo, Toranku, and Valoncia, who have started their own brand, Subtonic, and working on exciting new products together.

So that’s a heavy disclaimer here, as I have worked on Audio Discourse’s YouTube channel along side some of the folks involved in the creation of this product. This tour unit was loaned out to me from Symphonium directly, and this unit, along with a few others across the world, are being sent to various people in the community for feedback and impressions. All that said, as usual, I try to minimize as much bias as possible and have come into this with excitement, but also will provide my critical takes as well.

The Helios tour unit was sent with two copper-colored balanced cables in 2.5mm and 4.4mm varieties. These two cables are very soft and supple, and I find them both attractive and easy to use. They terminate in 2-pin connectors, and unlike most cables available, these cables do not have pre-shaped hooks.

The package also comes with a hefty round screw-on metal case that is polished metal and has a nice attractive and luxurious look to it. I am typically not a big fan of these screw-on round cases, but this one is pretty nice and I’d probably use it for storage at home.

The Helios shell design is a rounded triangular shape that isn’t too dissimilar from others like 64 Audio and Tachijim’s general shape and design. It is however quite large, and has a deep cavity and a longer than average nozzle that is also about 5.75mm in diameter. It is a bit on the large side, and is meant to for a deep insertion into your ear canal.

This can present some challenges to small-ear hole folks like myself. My left ear was able to get a deeper insertion than my right, as my left ear canal is just slightly larger and has a less sharp bend to it. My right ear is narrow and has an early and sharper bend, and so the nozzle length and diameter hits up against my ear canal a bit prematurely, and so no matter how deep I try to push it in, its maxed out due to the interference.

This causes the IEM to stick out a little further and at a kind of strange angle out of my ear. All that said however, with the right sized tips (in my case, SpinFit CP100 Small), I was able to get a tight seal and no real issues with pain or discomfort. It just didn’t look or feel as secure as I hoped it would. I did not have the same types of pain I felt with the Moondrop Blessing 2 or the Campfire Solaris despite them also having similar fitment issues due to nozzle length, width, and angle.

Sound Impressions

The Helios is a very well-tuned IEM that expresses a nice deep sub-bass presentation with clean lower-mids, and a smooth mid-range and treble response that falls in-line with my preferences. It can be perhaps a smidge bright but nothing really to concern about if I had to nitpick its tonal balance. I could also ask for just a little more mid-bass for extra warmth and smoothness, but man, this is a nicely balanced IEM that should be a great all-arounder for most genres.

If I had not known the quantity of the driver count, I may have thought there were more. The 4-BA configuration gets a lot of performance on this IEM, especially when I compare it to my beloved 4-BA Viento B Custom IEM. Yes, that one is several years old now, but it still stands strong in my opinion due to its fantastic tonal balance and coherence.

The Helios takes a similar tonal balance, but adds more sub-bass performance and adds a lot more dynamics to the overall quality. Bass has better texture and punch, and there’s a nice amount of sub rumble that can be felt in my ears. It can slam when it wants to, though not as much as some other IEMs I have tried of course. The Monarch and Odin slams just a bit more for similar sounding gear.

Symphonium’s mid-range is a perhaps a tad lean in the lower end, but has a nice balance in the upper mids where I don’t find it too lean nor too hazy. Some people may find this to be a tad lean overall given the entire mid-range response as whole, but for me personally, I really enjoy this presentation, which is slightly dry, but very clean and clear, and strikes a good equal balance to the spectrum.

Treble, despite being perhaps just slightly more elevated than I like, is very smooth. There is a refined and buttery slickness to it that reminds me of the best EST IEMs (i.e. Odin), or even the all-BA ultra-warm and laidback Vision Ears sets like VE8 and Erlkonig.

One of the most noticeable sonic impressions I found with the Helios, for good or for bad, is that it sounds like some notes or some frequency range sounds a bit more forward and closer to my ear than others. The midrange just seems a little bit louder than the rest, which is good for those who enjoy hearing the mids, and for some reason, I do feel like I am turning this IEM a little higher up on the dial than others. Still, I do find that I prefer a slightly more relaxed tuning, and at times I do think that the Helios’ mids are a bit aggressive.

The dynamics are very well done. Despite what I say in the last paragraph, there are nice varying levels of sound range here, and quiet moments come off quiet while loud moments are intense. It’s not the best IEM in terms of macrodynamics I’ve heard, but it’s definitely above average.

I spent a lot of time with the Helios in all sorts of genres and musical selections – anything from old classic rock, to jazz, to electropop and folk, to country and to classical. It does well with all genres. I did find it best for some music specifically though.

For example, the subbass gain, tacked on with the nicely tuned upper-midrange is a great combination for the newest Chvrches album, “Screen Violence.” The Helios does well with the electropop band’s mix of deep subbass synths, and Lauren Mayberry’s vocals. Even the dark, emotive track “How Not to Drown” featuring The Cure’s Robert Smith sounds fantastic on this IEM.

I also spent a bit of time listening to Massive Attack and Morcheeba, trip hop legends from the past with the Helios, and again felt it works well with this electronic brand of music. Helios provides the much needed deep subbass this genre asks for, while also the electronic synthesized keyboard play on full display.

I will say that my most listened to music of late, trio-based jazz music, is probably the least favorite stuff I have heard on the Helios. Perhaps it’s due to the lack of low-end warmth and just not having the real grunt of the double bass stand out, or the slightly forward piano notes being a distraction. This wasn’t my favorite combination for the music I played with on the Helios, but again, it is still very enjoyable and well-resolving for this music.

The Kilo-buck Market Competition

The Helios enters competition against a lot of other $1000-ish in-ear monitors that are very popular and very good. Here are just some of the ones I can think of off the top of my head:

  • Campfire Andromeda (2020)
  • Sony IER-M9
  • Hidition Viento
  • Thieaudio Monarch
  • Unique Melody MEST

There are definitely others to consider, but these are some of my top ranked IEMs and are tough, tough competition for a new company with a new kilobuck entry. How does it stack up?

The Helios’ defining difference between most of these IEMs is their sub-bass elevation and focus with the exception of the Thieaudio Monarch, which have very, very similar tonality. The Helios is more coherent, with better clarity and resolution from my memory versus the Monarch, and the treble is smoother. It’s also a little more costly at $350 more.

The Andromeda is quite a bit different sounding, while also sharing an all-BA setup. Both have good dynamics and resolution, while the tuning is where they go off on different tangents. The Andromeda is warmer with a significant amount more lower mids and midbass compared to the Helios.

The IER-M9 is also an all-BA setup, and just has a much different sound. It’s ultra smooth and warmly tuned and darker. Its a more relaxing listen and does not have a sub-bass focus. It’s been a while since I really listened to the M9, but I never felt the technical performance as compelling on first glance as I did with the Helios. It’s not saying that much, but perhaps it the smoother, warmer nature of the M9 not showcasing its full talents.

Finally, the two IEMs I do own: The MEST and the Viento…

The Viento is also a 4-BA setup, but I feel its tonally better than the Helios with similar upper mids and treble, but less subbass and more mid-bass warmth. It gives a more even sound throughout, while the Helios has probably a bit better clarity, texture, and excitement.

The MEST is quadbrid, that also has a subbass focus, but not nearly as energetic as the Helios. It also differs in the uppermids, where the MEST is quite a bit more relax and darker, given the comparison between the two very different flavors.


The Symphonium Helios is a really nice entry to the market. I am quite impressed by its technical ability and it has a tonal balance that I think will make it a favorite amongst many, especially those who enjoy electronic and other sub-bass focused music. It has a lot of the tangibles in place to really set itself as the top “neutral with sub-bass” top dog in a crowded marketplace. While I still prefer my Viento-B, another “neutral with sub-bass” IEM just a little bit more for its tonal balance and warmth, I can see the Helios being a close runner-up, but with better technicalities.

The biggest gripe I really have with the Helios is the shell design. It’s large, requires deep insertion, and I’d prefer a lighter acrylic shell over the metal housing it comes in, but for many, this might not be a big deal.

The Helios is good and a solid-buy. I look forward to the next Symphonium and Subtonic collaboration as I hear there’s something(s) even bigger down the road in the high-end market that gets me very excited. This is a teaser, and a really good one at that.


Has anyone tried throwing in a 2dB bump at 150Hz with a Q of 1 to see how it effects the “slightly thin” upper bass/lower mids?

This IEM is a serious contender for me right now.

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I haven’t delved into digital EQ yet with my tour unit. Playing with analog ASP on my iFi amps and the Schiit Loki+.

Had Been listening just before with my LCD-2 connected to an iFi iDSD Black Label DAC/Amp hosted by my trashcan Mac

Had a craving for some Halsey and decided to playback her latest 2 pop masterpiece albums, on each headphone, for an truly unfair apples to oranges comparison

Upfront, I’ll tell you, listening on this chain… this is the best sound I have.

To make this even more unfair, I’m running SoundSource’s parametric EQ, using the preset created by AutoEQ from the measurements generated by for the LCD-2F I have

So how does this stunningly performing in-ear instrument fair against, literally and figuratively, my heaviest guns?

Yeah, it was crazy unfair to do this

I’m confused by your wording. Are you saying you prefer the Helios to your EQ’d LCD-2 Fazor?

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Sorry i left it hanging like that. The setup and comparison were unfair. The Helios synergy and setup works great outdoors and on the go. They really are shining at this moment with the best tips for my own ears and nice DAP. Things are going better now.

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Getting a chance to spend some time with the Symphonium Helios - seeing if it lives up to the hype (no matter how sneaky I am, @taronlissimore hasn’t let me steal them from him until now). So far… it absolutely does.

Here’s the Symphonium Helios frequency response against my own IEM preference target (for now, I’ll likely tweak it a bit but this is ballpark):

This is definitely an IEM for me. It kind of sounds like CFA Andromeda level detail and imaging (within that conversation at least), with a more balanced tuning and tighter bass. If I had to nitpick, this has a similar kind of ‘lean’ effect for music that doesn’t token the full sub-bass range, not unlike what you get with the Thieaudio Monarch. But for stuff that’s well recorded, this is some of the best BA bass you can find. It’s very punchy.

For tonal balance, this sounds to me somewhere in between the Dunu SA6 (or 64 Audio U12t), and the Thieaudio Clairvoyance - a really solid balance between relaxed and ‘correct’, with strong and distinct sub-bass. I think a lot of people are going to like this.

Other aspects:
This will all depend on the individual, but for me the comfort is a bit… unique? I have no issues with the shell or how it sits on my ear (it’s very no-nonsense), but the nozzle is quite long and so I had to switch to smaller tips than I normally use to get the fit right. This may be one of those instances where long-term comfort is actually okay once you get over the initial nozzle violation. At least it’s more comfortable than the SoftEars RSV so that’s good. It might be worth experimenting with a variety of tips.


Super excited to see more people’s thoughts on this one.

I loved it, and between the U12t and this, it is on the to-buy list.


The more I wait to try this IEM, the more I worry about my wallet :smiley:


Haha, I feel the exact same way. Nonetheless, I look forward to getting my ears on it.


Here I my video on them


Great vid, thanks Tyler!


Thanks for pairing them with our stuff.

Can’t wait to get my Helios tour unit in a month or two!

From what I can tell, our stuff will do really well with it in general.

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Yeah, it did really really well. It seems to like some good clean amplification. Details really opened up with more volume, in what was quite a magical unveiling.

I think we need to refer to the Helios as the Tuxedo from now on - loved that visual analogy.


The following, as usual, is also available in Spanish on my blog and on YouTube, links at the end of the post.

The Symphonium Helios have been sent to me on loan from the company Symphonium Audio without a request for anything at all. I am very grateful for the loan of these IEMs as I would not have had a chance to try them out and they are certainly a set that have changed my view on IEMs as a whole, but more on that in a moment.

You can find the Helios on the Symphonium site here: Helios – Symphonium Audio

As always, my review and opinions will be as sincere and honest as possible but you do need to factor in two things, first that it hasn’t cost me anything to try out these IEMs and second, I may have already had some preconceived impressions of these IEMs before I even received them.

I will explain more on why I may have some preconceived impressions in a second but as I am someone who believes in honest and unbiased reviews, along with sharing as much information as possible, I have arranged with Symphonium to allow me to send these on to two other Spanish reviewers who know nothing about them. The Helios will be going to both Vertex, who posts his reviews on the YouTube channel “Auricular ORG” (in Spanish), and to Cqtek, who posts his reviews in English and Spanish on, so please check out their reviews as well (I have no idea what they will think of them but I do know that they will share their unbiased opinions!).

Anyway, with that cleared up, let’s get on with the Helios!


The Helios is a very recent release from a company called Symphonium Audio that has very few models and I only know about them due to the Helios and the talk of these IEMs in a Discord server that I am part of, along with people who worked on the design of the Helios and some reviewers whose opinions I have a lot of trust in.

This is the reason for the possible preconceived impressions that I mentioned, as I have heard nothing but praise for these IEMs since they started getting heard by those reviewers and by some other non-reviewers who have also had the chance to try them. It was actually quite an experience to see people try them and as soon as they passed them along, place their order for them. This obviously made me expect something great from the Helios, as there is no better positive publicity than people hearing them and then spending 1000€ to own them.

And that is another part of my impressions, I have never experienced a 1000€ set of IEMs before. In fact, it wasn’t too long ago that I said that 100€ was my limit for a set of IEMs and although I have broken that limit a couple of times, I am still a long way from having spent such an amount on a set of IEMs. The main reason is that I always prefer headphones, however, I have started to realize that I do use IEMs more than headphones, mainly due to the heat here for the majority of the year, so I have been more open to higher priced IEMs lately (although I still haven’t made the commitment).

All this is basically nothing to do with the Helios but I thought I would include this information as it gives you an understanding of where I am coming from with my impressions of the Helios, which I can already say is the best set of IEMs I have ever heard.


I am not 100% sure if what I have received is actually the same as what is received in a retail set of these IEMs, as I said, these are a demo unit, but I think that things like cables can be chosen when purchasing from Symphonium.

This set arrived in a black box, which I understand is the retail box, along with another case containing a second cable, wrapped separately.

The extra case is a very nice travel case which is (imitation) leather on the outside, sporting the Symphonium logo, with a nice furry interior. As I said, I am not sure that this case is included with the retail version but I have seen that it is available on the Symphonium webstore for $10 and it really is nice to have the lined interior. Inside this travel case they included a 2.5mm balanced cable.

Inside the main box we get a rather special aluminum storage case, which is round and has a screw off lid. I say this is a storage case as I don’t think I would personally use it for transporting the IEMs due to the size and weight of it, but again, it is very nice and does make it seem like you are receiving something special. The round case is located at the top of the box and has a metal plaque underneath that reads Symphonium Audio Helios. This presentation is rather simple but elegant, again, making it seem like something special.

Inside the storage case are the IEMs, a 4.4mm balanced cable, a small cleaning brush and tool, along with a few Symphonium Audio stickers.

The bottom end of the box has a small drawer that slides out to reveal another metal plaque with the serial number engraved, under which we find 6 extra sets of silicone tips, 3 sizes of large bore and 3 sizes of small bore. As this is a demo unit and I already have hundreds of tips in different sizes and styles, I haven’t actually used the included tips.

As far as the presentation, that about sums it up. Again, it is rather simple but elegant and includes enough accessories, although an unbalanced cable would have been nice but that will depend on the source that each person is planning on using.

Build and aesthetics…

Starting off with the IEMs themselves, they are very simple rounded triangles, all black, with Helios on one side and Symphonium on the other. To be honest, they are nothing much to look at, they are a simple shape and finish that does not jump out as being anything special, they certainly aren’t something that screams “expensive” to someone who doesn’t know IEMs, which can be a good thing depending on your use case.

They are also quite large and have a fair weight to them, with quite a long nozzle that is also on the larger side (although not to the extent of some nozzled like those of the iSine or Blessing). I found that a lot of tips didn’t slide all the way to the end of the nozzle, making the Helios stick out from my ears a little too much, although they still weren’t uncomfortable in this way. However, they are meant to be used with a deep insertion, meaning that I needed to select tips that are a little longer and also of a smaller size (as the seal happens further inside my ear). To be honest, I am not a great fan of deep insertion but they still weren’t too uncomfortable even when pushed deep.

The rest of the contents are of good quality, the accessories are great, as I mentioned, and the cables are nice. I guess my only complaint, which is not really a complaint, is that the cables do not have preformed memory wire or ear hooks, but that is not my complaint (I actually praise them not being preformed), it is the fact that the 2 pin sockets on the IEMs do not have a guide for the connectors and as the cables are not preformed, it makes connecting them out of phase very easy. This is easily overcome by looking at the channels on the connectors themselves, making sure they are the correct way round, but I can see people making mistakes and ending up with left and right out of phase by accident.


So, I already said these are the best IEMs I have heard. That is obviously enough to know that my impressions of sound are very positive, but that still doesn’t mean that they are perfect for everyone, or that they are even perfect for me.

I am going to go through my usual steps as far as sound but I want to point out beforehand that any negatives are minor and they are relative to what I want from a 1000€ IEM, not because the IEMs have any faults themselves.

As I have said with reviews of headphones, once we reach a certain sound quality, the rest is more about preference. That doesn’t mean that all headphones or IEMs above a certain price point are great, there are some that don’t hit the “certain quality” mark, but that is definitely not the case with the Helios, they surpass the that “certain quality” with ease, so it puts them in a zone where personal preference becomes the main deciding factor.

Starting off with the subbass, it is excellent.

Ok, I guess I better be a little more specific :slight_smile: The extension of the subbass is great, reaching far lower than my hearing range, providing plenty of rumble but keeping it very clean and articulate, never seeming to lose control over even the lowest frequencies.

Now, I already knew what the measurements of these IEMs looked like way before I got them, and also heard praise for the subbass, but even so, I was very surprised. As I have mentioned many times, I am not a bass head and the graph of the subbass would place these well over my preferences, but the sound doesn’t. The cleanliness and presentation of the subbass means that the power to rumble is there, but it doesn’t just add it to everything, it just presents what the track needs at each time.

I don’t think I have mentioned yet that the Helios is a 4x BA set up, which is something that doesn’t really attract me on paper. I am a lover of dynamic driver bass, probably due to the fact that I have spent all my life listening to bass from dynamic drivers so it is what I find natural. In the case of headphones, I said that the HE1000se (and now possibly the Arya Stealth Magnet version) were the first headphones to make me feel that I didn’t need a dynamic driver for bass tonality and it seems that the Helios can take that same claim for subbass in IEMs. The rumble, articulation, coherency are all just mixed together perfectly for my tastes in subbass.

I can’t finish the subbass section without mentioning “Chameleon”, which is usually a good stress test for an IEM subbass, however, in this case, it is more of a massage for the eardrum, giving a sensation of power that I have not experienced in an IEM before without it becoming overpowering and uncontrolled.

Moving up to the mid bass ranges, the articulation and speed are again there, making any tracks, no matter how busy in the bass areas, sound clean and never seeming to lack any dynamics in the bass area. However, and this is my first negative (which I repeat, is relevant to what I am looking for, not because it is bad), I feel that the midbass is lacking a little bit of warmth and presence to be totally natural on the majority of music that I listen to.

I listen to a lot of acoustic guitars and basses in my music preferences, some samples of which can be found on my test list, such as “Tears in Heaven” by Eric Clapton, “Free Fallin’” by John Mayer or “Seven Nation Army” by Zella Day, just to name a few. With this kind of music I find that the acoustic guitar (and upright bass in something like “Back it Up” by Caro Emerald), lacks a little bit of body to meet my preferences for these instruments.

I know by looking at the graph that the mid bass is slightly below my preferences as far as presence but even with a little bit of EQ in this area, I still don’t find it to be as natural as I would like, which I think could be due to these frequencies being handled by a BA and not a DD. Again, I must stress that this is some very minor nitpicking on my behalf, it is not that the instruments sound totally off, far from it, they just don’t seem to have the body that I love about the midbass of an acoustic guitar or bass.

When listening to similar styles of music that uses electric guitars rather than acoustic, such as “Give Me One Reason” by Tracy Chapman or “Sugar” by Francesco Yates, I do not get this same feeling. I feel that is more relative to the fact that I have been listening to acoustic guitars in a live setting (unamplified) since, well, forever, and it makes it difficult for them to sound the same.

With tracks that move more towards rock, such as “Whole Lotta Love” by Led Zeppelin, then I find the midbass to be great, with great clarity and coherency that makes it possible to even appreciate effects used in dirty tones such as “Bombtrack” by Rage Against The Machine.

Moving out of the bass and into the mids, there is no need to mention the transition as there is absolutely no hint of anything that resembles bleed or bloat. This is obviously helped by that small lack of presence in midbass (in comparison to other sets) but also the fact that these IEMs are so clean and fast that it is not even something to consider.

The mids themselves are very well presented, keeping up with that clarity and speed found throughout the whole of the frequency ranges. Voices are clear and upfront but without becoming harsh or pushing their way too far forwards. From vocals such as Dominque Fils-Aimé on “Strange Fruit”, through to Beth on “Don’t You Worry Child” (who can easily become harsh), I have no complaints about them at all. There is great balance between the male and female vocals on tracks such as “Billie Jean” by the Civil Wars, without either overshadowing the other.

Songs with multiple voices, such as “Hallelujah” by Pentaonix or “These Bones” by The Fairfield Four, are separated perfectly and allow all the layers to be easily identified. I also need to point out that the very deep voice on “These Bones”, which could possibly be affected by the midbass that I mentioned earlier, does not seem to be lacking in warmth at all, which goes to prove even more my point about it being relative to my expectancy of the acoustic guitar rather than the IEMs.

Moving up into the higher regions, I must say that this is by far the best treble I have heard on a set of IEMs. Everything is smooth, articulate, airy, all those words that actually mean nothing but serve to try and explain the sound. There is no issue with sibilance, although it doesn’t tame it either, so if the track is recorded with sibilance, the Helios is not going to hide it. I can see that maybe the treble would be slightly too much (but only slightly) for some people but personally I really can’t pick faults with the treble of the Helios, it is great and, again, by far the best I have heard in an IEM.

The soundstage is also way above the average I have come to expect from IEMs. I mean, it is not an Arya v2 (nothing is really an Arya v2) but it does place itself in the category of being open and spacious, something that is not common on IEMs that I have tried.

Something that helps add to the spaciousness is the detail and placement of images inside the soundstage. This means that it makes the most of the space that is available, placing images in a way that makes it easy to appreciate small changes in placement and making the whole picture seem larger than it actually is. This is by far the most detailed IEM that I have heard also.


I think that I have made it clear that I am very impressed with the sound of the Symphonium Helios, as I have already said a couple of times, it is easily the best sounding IEM I have heard. The details, spaciousness, sound signature, there really isn’t anything that can be called an issue, it is just an amazing set of IEMs.

Now, I guess that thousand euro question is… would I actually spend a thousand euros on the Helios?

Let me say that I am very tempted and just the fact that I am even contemplating spending this kind of money on a set of IEMs is proof that I am really impressed with them.

So, what is stopping me?

Well, apart from the fact that I still feel that 1k is a lot of money for a set of IEMs (it was only a year ago that I thought it was crazy), if I was to spend it, I would want something that is perfect. By this I don’t mean a perfect set of IEMs, I mean something that is perfect for me, and there are really only two things that I don’t find perfect about the Helios for my personal taste.

The first is comfort. While these are not uncomfortable IEMs, they are also not the most comfortable IEMs I have worn. I always notice them in my ears. As I said, I am not a fan of deep insertion and these do go a little deeper than my preference. I can also get a good seal by using tips that sit further away from the shell and they still sound great, but not quite as amazing as when inserted properly. I also find that the back part of the triangle shape rests on my ear and the top sticks out at an angle, causing the cable to be at a weird angle also, which is not terribly uncomfortable but it is something that I notice constantly.

The second thing that has me hesitating is the mid bass / lower mids timbre that I mentioned. With almost all music except for that based on acoustic guitars and basses, this is not even an issue, however, a very large part of my listening is based on music that revolves around these two instruments. Again, this is not bad by any means, far from it, but it is just not the perfection that I would hope to achieve by spending this much on a set of IEMs.

Now, both of those reasons are completely personal. Comfort is a very personal thing and my impression of an acoustic guitar’s natural timbre may not coincide with yours. You may not even listen to any music that involves acoustic instruments at all, in which case I would not be able to point out a fault at all as far as sound. I have listened to all kinds of music throughout the week and there really isn’t any genre that I haven’t enjoyed on the Helios. Even music that is based on acoustic guitars has been thoroughly enjoyable, I really am nitpicking when I talk about that “body” of the instrument.

You might even be someone with plenty of disposable income and think that 1000€ is a very reasonable price, which I guess it is in comparison to other IEMs that are twice as expensive, or even 3, 4 or 5 times more expensive. I obviously haven’t heard any of those more expensive models but based on commentary from people that I trust, I don’t think the Helios has anything to worry about as far as sound quality in comparison.

So, I am still on the fence about the purchase but what I am not on the fence about is the fact that they are an amazing set of IEMs that I am very grateful to Symphonium for sending out to me, giving me the opportunity to get to hear them.

As I mentioned at the beginning, I am sending these on to Vertex and Cqtek for them to share their unbiased opinions of these IEMs as, again, I might have already had a preconceived opinion before starting this review, so I would suggest checking out their reviews once they have had chance to publish them (heck, they might not even like the Helios!). I will update this review with a link to their reviews once they are available.