Heir Audio 10.A CIEM Review


Heir 10a Review Heir Audio 10.A CIEM Review: The 10.A’s are one of the finest pairs of CIEMs that money can buy. The craftsmanship is very good even if more artistic approaches should become available, the audio quality is detailed, ever so slightly warm, and highly revealing, whilst the overall package is exceptionally thoughtful. Purchasing the 10.A’s will, undoubtedly, be one of the best audio purchases that you will ever make.


Heir Audio is a Chinese boutique manufacture of high end balanced armature (BA) IEM and CIEM designs. With an extensive range that accommodates a whole plethora of budgets and sonic tastes, the 10.A currently stands as Heir Audio’s reference flagship model. Having said this, Heir Audio have confirmed that a new top-banana twelve BA design is in development, so if you’re looking for the ultimate then it’s best to head over to the Heir Audio website to check out the release date, or to keep an eye out for our forthcoming review. Regardless, the 10.A still packs serious heat, as you’ll read about within this review, but it does needs to be understood that it is currently only available as a custom so you will need to have your ear impressions taken and sent to Heir to produce your one of a kind. At $1399.00 a pair some may be questioning their prestige price-tag, but I can conform that they are certainly well positioned and won’t leave you with any regrets the moment that you hear their siren song.

Unboxing, Presentation, and Included Accessories:

Heir 10a Review With every product, Heir Audio include a nice crush proof Pelican style protection case and cardboard sleeve. In terms of the 10.A’s, Heir have ditched their usual stainless steel with red logo nameplate for a luxurious gold design, and will even CNC mill your name into the 6.5” x 4” x 1.5” ultra strong ABS plastic case for no fee whatsoever. Internally your CIEMs, and included accessories, are adequately protected with a 3mm thick high density foam lining, and the case even has a rubber gasket with two click-clips to make sure that the entire design is water resistant.

If the included hard case isn’t quite your thing, or feels awkward for ‘on-the-go’ transport, Heir have included a small branded short pile velvet drawstring bag for storage. The bag itself feels moderately well made, and is actually large enough to store a small DAP instead of the CIEMs if you so wish (ie. iBasso DX50/DX90 or AK100). Alongside the drawstring bag, Heir have nicely included a couple of branded rubber DAP straps, a VIP card (more on this later), an industry standard gold plated 3.5mm to ¼” adapter, dual prong flight adapter and, of course, a small universal cleaning brush with ear wax hook. In order to keep your CIEMs on top form you’ll need to make sure that you check the tri-bore design is clean and clear of foreign objects and prevent a wax build up. With CIEMs it’s always good to have a fine layer of wax on the outside of the bore as it helps with the fit and maintain a good seal, but it’s all to easy for a build up to occur on the inside. This build up will change the sonic characteristics and, over time, will clog up the respective frequency bores. A good tip to help you keep on top of things is to opt for transparent, or translucent, canals with your design to help make your job a to easier. This does add a meagre $30.00 onto the cost, although if you choose to order a transparent/translucent shell design you need not worry.

Heir 10a Review Earlier we mentioned the inclusion of a VIP card within the 10.A package. Although, at first, this card seems a little odd, this item is unique to the 10.A CIEM package and includes an individual VIP number. Not only does this card list your unique serial number and 10.A ‘born date’, but it offers the purchaser a range of benefits including; a one time 20% discount off your next purchase, lifetime 10% off new orders, unparalleled exclusive customer services (Phone, E-Mail, and Skype), 10% off a repair or later refit, and free shipping twice. I haven’t quite seen this level of customer service with any product before, so I can only say that Heir Audio’s generosity is outstanding and can be of significant benefit – especially if you’re a repeat customer. On top of all of this, Heir Audio don’t just stop there, they offer a two year warranty with their IEMs and CIEMs so you can rock on knowing that you’re at least safe for that period.

Ordering, Build Quality, and Features:

Whilst there are a number of boutique retailers that can take your impressions and perform the ordering process for you, ordering your CIEMs direct from Heir is a quick and easy process that is simply done through their online store form and settled through PayPal for peace of mind. As mentioned previously, the retail price for the 10.A’s is $1399.00, but if you choose to wait Heir do typically offer great discounts over Black Friday and the Chinese New Year.

As the possibilities appear endless, you do have to take into account the limitations of working with such a tiny product. An example of this is that I initially ordered a Rosewood Faceplate with a silver boarder and the Heir crown in hammered gold. Unfortunately the silver boarder was difficult to do and the hammered gold finish on the crown was also not viable, so in the end I had to compromise with Heir to end up with the design that you see in the adjacent pictures. Thankfully during the entire redesign process Sunny kept me updated and helped me to select a design that was viable and would look great. Before you go ahead and select your design I would advise you to send Sunny an email to check whether the design that you want is something that they can easily do as it could potentially take some time to amend, because if you then choose a significantly amend design then you will end up having to pay a $79.00 process fee.

Considering that Heir are known for their bespoke wooden faceplates I’d advice a design based on this classic appearance, but ultimately the option is up to you and there are thousands of possibilities when you look at the order page. If you do wish to purchase for a rush order, then Heir will manufacturer your CIEMs within seven days after receiving your impressions. The problem with this is that, at $280 per order, it is exceptionally expensive. I would like to see this price significantly drop to be fair to the customer and potentially increase rush order transactions. To put things into perspective (from the UK), it took one week via Royal Mail Signed For International for my impressions to arrive at Heir Audio HQ, it took a further five weeks for CIEMs to be made, and finally a week to arrive via DHL – during which they were traceable at every single stage (even though they seemed to be inbound/outbound scanned in more countries than you can shake a stick at). The production time period of five weeks is fairy acceptable due to their custom nature, and is a similar lead time to their competitors, but it’s certainly not speedy by any means. Also if you are wondering what happens to your trimmed impressions, I noticed that Heir did not send these back to me. I would have liked them back for curiosities sake but, if you plan on purchasing more Heir CIEMs, you can pay $50 for them to store your impressions for two years – much cheaper than going back to the audiologist!

The main cable that Heir include with the 10.A is the Magnus 1. We’ve previously discussed the Magnus 1 on the site and have praised it for a neutral detailed sound signature and robust build quality. At 1.4m the cable is more than adequate for most users and it sports a striking quad braided design that both functional and aesthetically pleasing. The internal core conductor is Oxygen Free Electronic (OFE C10100) Copper cable with a silver coating, tin foil insulated, and reinforced with black Kevlar before being coated in smooth PTFE plastic. Unfortunately the cable does have one flaw, and that is with the Y-Splitter because it has no individual housing to protect the braid and direction, instead Heir have pinned their hopes on two layers of heat-shrink tubing – very disappointing considering that the cable alone is meant to be exceptionally strong. In terms of the connectors, Heir use non-recessed 92pin CM sockets so the Magnus 1 is terminated as such with gold plated terminals and clearly labelled L/R aluminium posts. At the other end the cable is fitted with a 90° gold plated gun metal Neutrik Jack, which helps to reduce strain on a DAP’s output socket. Despite the fact that this cable’s construction is very good, some may feel the need to upgrade it to get the best sonic performance out of their 10.A’s but, also as the CM sockets have memory wire, some glasses wearers may be irritated by this.

Heir 10a Review Alongside all of the included accessories, and included Magnus 1 cable, Heir Audio go one step further with the 10.A and allow the customer to pick between an extra Techies Android or iPhone cable. This 1.3m cable appears to have an internal structure that is similar to the Magnus 1, but adds basic Play/Pause and call functionality. Instead of having a raw separate quad braided conductor design, this ‘Technas’ cable appears to apply a similar principle beneath an extra smoother black PE skin, but you can opt for a white variation instead. However, if you choose the Android comparable cabe it’s important to know that the cable only comes in one colour; white. Essentially the 92pin CM socket connector is fundamentally the same as the Magnus 1 cable, although the 3.5mm connector follows a completely different principle as it points 180° instead of 90° on the Magnus and has a slim aluminium billet design. If we follow our eyes up to the Y-splitter we will see that, again, it differs from the Magnus 1 with the use of a much more reliable aluminium splitter. Why this design wasn’t also implemented on the the Magnus 1 I’ll never know, it just doesn’t make sense, but it would certainly be a hell of a lot better than the heat-shrink tubing. What does seem to make sense is the placement of the activate call button and microphone. Thankfully Heir have placed this small plastic housing 20cm past the Y-spliiter, and in the most logical positioning – next to the mouth, and at a position that doesn’t involve undoing coats or moving clothing out of the way to make the microphones call quality better. Having said this, it leads us nicely on to discuss the reliability of the switch and microphone, and I have to say that everything is more than adequate in this here. Personally I opted for the iPhone cable and, in use, the switch has a nice degree of firm resistance so it isn’t accidentally activated. Away from calls, I found that Siri could be swiftly initiated and the voice recognition accurately understood my commands no less than just speaking straight into the phone. During call tests I found that the recipient, on my end, was loud and clear although I did find that not having access to an in-line volume up/down rocker switch was a tad awkward. On the flip side, the recipient commented that I came across clearly, at an adequate volume, and without too much distortion at all, but I do have to say that the microphone is of a good quality and apparently FaceTime audio calls sounded even better – nothing is lacking here! With functionality aside, I have found that this cable doesn’t quite have the same resolution as the Magnus 1 cable. In comparison, this Technas cable just isn’t as dynamically rich and the general performance is sonically veiled, but hey! The 10.A is a premium product that is designed to be used with a premium source so, with a limited source, you can only expect limited quality.

Despite the fact that silicone shells are slowly becoming popular with rival CIEM manufacturers, all of Heir’s products are only available in acrylic, including the 10.A. Even if Heir did adopt a silicone design, the internals of the 10.A would simply not fit, but Heir choose to focus on what they know and they clearly do it well! In fact prior to sending my impressions to Heir in China I was skeptical about whether they would be able to fit such a complex design into such a confined space, but incredibly the engineers managed to pull it off a seemingly impossible task without the design protruding too far from the outer ear. So, what makes the design so complex? Well, like the name suggests, each 10.A shell packs ten precision matched Knowles balanced armatures arranged into a four way passive crossover design thanks to the careful implementation premium AVX OxiCap capacitors and Vishay resistors. This design results in two BA’s being used for low frequency production, a mighty four balanced armatures for the midrange frequencies, again another two BA’s for high frequency production, and finally two for the super high frequency production. In order to allow the 10.A’s to pair well with DAPs Heir have thankfully kept the impedance to 26Ω, which ultimately makes the 10.A’s relatively easy to drive without an external amplifier and perfect for both portable and at home listening. Finally it’s notable that, in order to save precious internal real estate, Heir only opt for non-recessed sockets. The benefits of this design is that you can be sure that a wider range of third party (92 Pin) CM style socket cables can be used with your precious 10.A’s so feel free to go forth and explore the sonic possibilities.

Review Equipment, Fit, and Isolation:

Heir 10a Review Various lossless files from 44.1kHz 24bit to 192kHz 24bit, MacBook Air Mid 2013, Sonic Studio – Amarra, Channel D – Pure Music 2, iBasso DX90 (2.1.8 Lurkers Mod), Chord Electronics – Hugo, Aurender – Flow, Lynx – Hilo, iPhone 5s, and Comply – Custom Wraps.

Overall I have found the work of the craftsmanship very good and the Heir engineers have adequately judged the tolerances from my open mouth impressions. In use the seal remains consistent (moderately tight) without too much movement and, over time, the CIEMs do not need to be readjusted too much. My only complaint that is during open mouth vocal exercises I have found the seal to be a little loose, so to remedy this I have used the Comply Custom Wraps. Installing the Custom Wraps onto the CIEMs was a quick and painless process and has genuinely improved the bass articulation, presence, and imaging – more than I ever thought that they would. For this reason, when you purchase your 10.A CIEMs, I strongly advise that you purchase a pack of the Comply Custom Wraps as they make the CIEMs fit even tighter, whilst adding a luxurious comfort, and improve the sound quality. As a final note of this thought… if you intend to use the 10.A’s for live performance purposes, the 10.A isolation is perfect for this environment as it easily blocks out foldback monitor performance (critical if you’re the only one in the band with a pair of CIEMs) and, again, your individual CIEM foldback mix will be adequately isolated to judge your performance pre or post effect – whatever allows you to perform better.

Another key aspect of the 10.A design is how well they isolate the wearer from external ambient noise and vice versa. On the Heir Audio website they claim a -26dB external noise attenuation, and this is certainly noticeable when worn. In use I have found the external ambient noise rejection to be so good that I can moderately hear my heart beating when no music is being played. This is not only testament to the build quality and craftsmanship, but it also means that you are getting a more than adequate seal so you can be sure that you are listening to your music in the way that Heir intended. During external listening tests I found that I could enjoy my music to near-dangerous levels, and my assistant noticed that the leakage, in a silent room, was negligible. If you are one of those people that worries about whether fellow commuters can hear your music, or not, you really should not worry with the 10.A’s at all – the attenuation is significant. To put this into perspective, I was able listen to heavily compressed Pop music (Sia – 1000 Forms of Fear) on my iBasso DX90 with the gain setting marked at ‘High’ and the volume set at 216 without my assistant even noticing that music was being played back – incredible.

Sound Quality and Previous Flagship Micro-Comparison:

The Heir Audio 10.A’s are an outrageously exquisite pair of CIEM’s. Clearly the 10.A’s are some of the finest pairs of ear candy that we have ever come across and I can comfortably say that, without doubt, they easily rival speakers costing many times their value. I totally understand that you may already be screaming ‘Lay off the superlatives!’, but I cannot sing their praises enough – I’m hooked and I know that you would be too. One of the most impressive qualities of the 10.A’s is that, somehow, they are able to bring the very best out of any Genre, recording, and even pair beautifully with almost any source that you have available – although certain devices, such as the DX90 (2.1.8 Lurkers Mod), have a delightful synergy with the 10.A’s. However, if you compare the 10.A’d to the previous Heir flagship, the 8.0’s, the 10.A’s are leagues ahead in definition, treble extension, and imaging, whilst they lay off on the heavy warm rounded bass presence in favour for beautiful lush textured mids to compliment the mid-fast dynamic attack and sheer distortionless super high end definition.

To put the 10.A’s in to perspective, I’d have to say that they exhibit a revealing, yet smooth, ever so slightly warm balanced character. The image is very wide and goes very deep to the point where you can draw attention to micro nuances within the micro details if you so choose. The super high trebles extend well beyond what is expected, but the lack of distortion makes this area very tangible so you can pump the 10.A’s up high, if you so wish, and never experience sibilance or premature listening fatigue, and likewise still maintain an excellent stereo image with superb layering. Essentially the 10.A’s exhibit a mildly fun, yet analytical, attitude in order to deliver a universally accepted performance that doesn’t intend to fit into any stereotypes or ostracise any specific genres. The 10.A’s certainly aren’t quite reference because they do have a mild U shaped frequency response… almost as if what we describe as ‘American’ sounding had a child with the ‘British’ sound – that’s the 10.A’s in a nutshell.

Despite the 10.A’s being energetic and emotive, if we come back to the stereo imaging, we should really discuss the separation and limits of each frequency boundary. If we begin at the sub-bass frequencies, it has to be said that they have a dryer stereo separation in comparison to the rest of frequency range. This is actually highly desirable as it acts as a solid central reference point for the range and positioning of the X-Axis, but the 10.A’s deliver a continuous tight biting stereo separation for the transience of the beat to be build upon… something that we shall discuss in the nest paragraph. In the general bass region the 10.A’s typically follow a similar path to that of the sub-bass frequencies, but instead they have a tiny bit wider, yet still central, positioning. I have found this modest area of breathing space to be highly desirably as, against the treble X-Axis extension, they naturally compliment each other and allow heavy bass instruments in orchestral / classical music, such as timpani’s and double-bass (harmonics), to come across with accurate grandeur and spatial awareness along the X and Y-Axis. As the bass frequencies progress into the low-midrange the stereo separation and depth exponentially expands to untethered boundaries – essentially the 10.A’s don’t appear to shackle the listener to any specific width and depth, so the listener only hears a sense of space as it was crafted by the mix-engineer. This is an outrageously difficult ideal to achieve when designing any form of transducer, or indeed transducer array, and it suggests to me that the 10.A’s have followed a lengthy tuning/matching process to achieve such harmony. With the right high resolution recordings, and equipment to match, you can expect to feel as if you are directly plugged into the intended spatial surroundings – the 10.A’s are pure bliss. As we progress from the mid-range into the high midrange, I have to say that nothing much changes apart from the fact that there is a slight dip in the frequency range, but still the same luscious, expansive, qualities that we previously discussed are applicable, just slightly lower on the Y-Axis. Having said this as we enter the low-high-range to mid-high-range the same expansive quality is evident and that highly praised spatial environment around the Y-Axis is restored. If we continue further on into the high-treble range it appears as if we’ve lost some of the depth resolution on the Y-Axis and X-Axis spatial separation, yet this feels entirely appropriate. The reason for why this feels entirely approbate is so that the articulation and central positioning of the bass groove can relate to the, often, rhythmic sizzle of supporting percussion. From this you don’t quite get a sibilant performance, but you do get an edgy presentation that screams definition. This slightly flatter image is quite fun to listen to, but this generally summarises the 10.A’s performance perfectly – they’re a multifaceted energetic CIEM that delivers a shockingly addictive performance that can relate to both audiophiles and the average consumer.

In terms of dynamic range, the 10.A’s are such a contrast rich pair that have the ability to nimbly navigate the range with sheer natural progression. In the high-mids to upper treble range the 10.A’s have an ever so slight edgy bite due to their moderately fast attack and slightly faster decay, yet the dynamic synergy between this specific area of the frequency spectrum is well judged and generally more than adequate to gel critical finer room reverb reflections into a coherent, well judged, convoluted transient window into the intended final mix environment. Coming down to the mid-midrange now, the 10.A dynamic range follows a flipped typology, in that they sport a mid-fast attack and a slightly slower decay. The resultant performance is perfect, to my ears, for a wide variety of genres and allows a myriad of multi layered vocal performances to have a sense of realism due to the sheer dynamic depth of field that’s exposed. With the 10.A’s the blacks are certainly as black as one could possibly hope for and likewise the finer white areas appear perfectly placed. This doesn’t solely come from the nimble acrobatics of the treble and midrange, but it also largely comes from the power and emotion expressed through the timing articulation of the bass frequencies… needless to say that this is, again, and area in which the 10.A’s excel at. In terms of the sub-bass frequencies the 10.A’s have a perfect moderately fast attack and moderately slow decay timing measurements coupled with a steady, distortionless, deeply low depth of field… and boy do they go low without ever loosing the reigns. The 10.A’s, slightly unnaturally, orchestrate the sub-bass frequencies in a regimented fashion in order to pull out the best of this region for your brain to translate it with gut wrenching emotion. With this said you shouldn’t confuse this statement for meaning that the sub-bass is too far forward, instead it is held in the right balanced measure – we’re not talking ultra artificial here, we’re talking about honest sub-bass slightly brought forward that is balanced against the expansive treble depth of field. With this said if we come up to the bass region, the attack here is slightly faster than the sub-bass and holds a moderate decay. Against the sub-bass and the midrange, the coherent transient nature of the bass allows melody supporting bass instrumentation to hold a rounded smoothness against an emotive pumping kick drum. Simply put, the 10.A’s never miss a beat and are so full of emotion that even the most serious audiophile will be rendered into submission.

Review Conclusion:

If, like me, you believe that the micro details are just as important as the macro’s, the 10.A’s will not disappoint. Their highly detailed and well crafted imaging is on par with speakers costing many times their price, and their oddly charming and transparent mild U-shaped frequency response is, no matter who you are or what genres you listen to, audiophile bliss. The 10.A’s are a dream to use and will have you hooked in seconds. The Pro Audio Web Blog awards the Heir Audio 10.A CIEMs with a full five star rating and the Editors Choice Award. Now rediscover your music collection…

Recent Content