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Periodic Audio Carbon IEMs – Detachable Cables, Attracted To Bass

Periodic Audio Carbon IEMs – Detachable Cables, Attracted To Bass



Periodic Audio decided to refresh their IEM like with detachable cables, and a slightly tweaked sound, so today’s review will focus on the flagship Carbon, priced at 500 USD, and which will be compared to other popular IEMS in the price range, including Earsonics Onyx (560 USD), IMR Audio Ozar (500 USD), Campfire Audio Holocene (650 USD). 







Periodic Audio is a company from the USA, and which takes great pride in producing IEMs as well as amplifiers and DAC/AMPs that have a scientific flavor to them. Each one of their IEMs has a base element that they coated the driver membrane with, and which changes the sound drastically compared to the others. Since the IEM chambers, design elements, cables, tips and all of the other elements are the same, Periodic Audio is most probably relying on the differences between those coatings to tweak, tune and voice their IEMs. The company has superb support for their customers, and I know friends from Romania who own Periodic Audio IEMs, and who are really happy with them, as they have a reliable quality, and superb sonics. Periodic Audio Carbon has 5 years of warranty in the United States, and 2 years of warranty everywhere else. Happily, most Periodic Audio products are available on Amazon, so you can choose between Amazon and their website, which accepts paypal, for a worry-free shopping experience. 



It is a good idea to reference my original review on the Carbon, the variant with non detachable cables, to get an idea of how things changed with the release of the new variant. 


It should be noted that I have absolutely no affiliation with Periodic Audio, I am not receiving any incentive for this review or to sweeten things out. I’d like to thank Periodic Audio for providing the sample for this review. Every opinion expressed is mine and I stand by it. The purpose of this review is to help those interested in Periodic Audio Carbon find their next music companion. 




Product Link


You can grab one from www.amazon.com here: https://amzn.to/3JMy4cK


If you’re in the UK, you can grab one from www.amazon.co.uk here: https://amzn.to/3uEPqUK


And if you’re from Europe, you can grab one from www.amazon.de here: https://amzn.to/3JDBM8t






First things first, let’s get the packaging out of the way:





All of the Periodic Audio IEM packages are exactly the same, except for the technical information and the IEMs found within, so it is interesting to see that they provide a nice package with their IEMs. Inside the package we can find:



  • The IEMs
  • One detachable cable
  • Golden Carrying Case
  • Gold Plated TRS Adapter jack from 3.5mm to 6.3mm
  • Gold Plated Dual Mono Adapter for airplanes
  • Memory Foam tips – 3 pairs
  • Dual Flange Tips – 3 Pairs
  • Single Flange Silicone Tips – 3 Pairs




Build Quality/Aesthetics/Fit/Comfort


At a technical level, the Carbon is a really well made IEM, with a ton of scientific research behind the IEM itself. The company has lab grown diamonds, 8 microns in thickness, as a layer over the proprietary polymer used for the drivers. Periodic Audio takes great pride in engineering their IEMS from 0 to 100% in house, with their own tools and research. 


Generally speaking, carbon has a higher stiffness, but is lighter than any metal, so it should theoretically provide the best material for sonic membranes, as it can move the quickest, but should also have the most control. 



Although the IEM shells look kind of cheap, that is because they are incredibly light, and inside they have superb acoustics, as Periodic Audio redefined those with an even lower noise and resonance than their previous IEM releases. Periodic Audio has been working with Eastman Chemicals to develop the materials needed to refine the C IEM, and Carbon uses the Tritan Copolyester for the material of the Carbon IEMs. 


If you see something new, that is the detachable cable, and Periodic Audio changed the design of their IEMS to have a 2.5mm IDEEL Connector. This is the world’s smallest 2.5mm jack, and it has 3.6mm across, with a 9.5mm housing depth. Theoretically, the 2.5mm plug is more solid than 2-Pin or MMCX, but it is considerably larger than both. I do wear it over-the-ear for lower microphonic levels, as I have a bit of a beard and I can hear the cable brushing against it, but the IEMs seem designed for straight-down stealth wearing. 



We have a normal 32 OHMs of impedance, which means that Carbon is not overly sensitive to hiss and output impedance, and we also have a somewhat low sensitivity of 98 dB, so you will need some extra power to drive the Carbon, but most portable DAC/AMPs should do just fine. The THD is lower than 0.2% at 1mW, so C is good for classical and super busy tracks too, at least in theory. 


At a subjective level, the Cabron is lightweight, fun to wear, but can only really be worn straight-down. Since I do not have any other cables to compare the original cable to, it is hard to say how it changes the sound, but it is probably the most flexible, lightest cable I’ve seen on an IEM to date. It feels slightly sensitive, but it didn’t break during my photoshoot and usage tests, or when it was thrown in my backpack and crushed by the camera equipment, so it should be strong enough for most folks. Of course, aftermarket cable makers could offer cables like Evo 1 from Effect Audio or Plussound Copper+ with the right jacks, but I never needed a 2.5mm cable for IEMS before, so I do not have any around the house. It is also important to notice that all periodic audio IEMs are single ended only, with no options for 4.4mm balanced connectors at this moment. 



There’s some minimal microphonic noise coming from the cable, and the IEMS do not have any driver flex. The IEMs are fully symmetrical, so the differences between left and right are given by the cable, rather than the IEM shells. There is absolutely no hissing or background noise I can hear with Carbon, and it is generally pleasing to wear and use, once you get used to the cable. Although physically, I do see the connectors as being a bit large and hard, wearing the IEMs over-the-ear provides absolutely no issues for me, and in practice, Carbon is one of the most comfortable IEMs I’ve tried over the past year. 



Periodic Audio C Carbon isolates well from the outside noise, with about 15-25 dB of passive noise isolation, depending on the frequency, enough for casual listening, and they leak a little bit, but unless you’re blasting music, most people won’t notice that you’re even listening to something. If you’re playing music, even at medium volumes you will not hear anything from the outside, as I had my girlfriend screaming at 1 meter away from me and I couldn’t hear her at all while wearing the Carbon. 




Sound Quality


Periodic Audio is well known for high-quality IEMs with excellent sonics, so I was quite excited when I heard that they improved their Carbon IEMs with a better cable, and hopefully with even better sonics. I have allowed the Carbon over 100 hours of burn-in, and used them with a multitude of sources, including iBasso DX300, Lotoo PAW 6000, Astell & Kern SE180, Khadas Tone2 PRO, Dethonray DTR1+, and FiiO M11 PRO. Carbon shows no hissing or background noise with any source, and is generally safe to recommend even for smartphones, but it eats quite a bit of volume, needing around 95 / 150 on Astell & Kern SE180 for a satisfying listening experience. As far as the pairings for Carbon go, they sound best with warmer, thicker, fuller and smoother sounding sources, including iBasso DC05, iFi Hip-Dac2, Astell & Kern SE180, Hiby FD1, Palab M1 Mini, and Tempotec E35 Sonata DAC.



The overall signature of the Carbon can be described as thick, full, heavy, V-Shaped, with a strong treble, and good emphasis on the lower treble and upper midrange, and with a recessed main midrange. The sound has tons of body and impact, a lush presentation, with tons of details, and Carbon is best listened at medium and lower volumes, sounding more aggressive and more V-Shaped at higher volumes. Carbon generally sounds best with EDM, Pop, Dubstep, Electronic, Classical, Jazz and Cabaret music, and Rock. The signature is super detailed, and presents music as it was recorded, with good emphasis on female voices sounding sweet, and male voices sounding deep and realistic. A perfect song is Geoxor – Bloodlust, where you can hear every little reverberation in the bass, but all of it is super full, rattles your jaw, and provides a subwoofer – concert like experience from the Carbon. C also has a tendency to emphasize macro details and macro textures, for example the texture in a guitar riff is quite obvious, but it has a natural way of doing this, so it doesn’t sound like Chifi brightness, and it rather sounds close to real life guitar texture. 


The bass of the Carbon is super full, deep, and has one of the best reaches from any IEMs out there. Exactly like the original C released by Periodic Audio, the bass can be said to be the central focus of their sound, but it is well balanced by the treble which is also fairly emphasized. With Cabron, you really hear bass guitars, but not just the bass notes within, but also the texture and overall notes of bass guitars. With Pop and EDM music, the bass is super full, deep and has a really satisfying presentation. The bass is emphasized up to the upper bass, which gives all music some extra thickness, and some added decay to each bass note. The overall speed of the bass is natural towards slightly slow, and provides a satisfying – natural decay to each note, having superb definition and low distortions even if you’re listening loud. 





The midrange of the Carbon is detailed, recessed behind the bass and the treble, but has a super sweet presentation for female voices, and a deep, lush presentation for male voices. Guitars are textured, and most instruments have a full, bountiful presentation, inherited from the uplifted bass, as Carbon plays music with tons of soul and depth. The soundstage of the Carbon is wider at lower volumes, and the sound gets more focused at higher volumes, but you still hear a lot of information and instruments playing in the background, as Carbon excels at providing detail alongside impact and dynamics. Indeed, the sound is very dynamic, and you can easily EQ some of the treble or the bass out, if you want to get a more midrange focused presentation from the Carbon. 


Carbon has super low distortions, and it is super easy to notice new effects, new background instruments and more details in music compared to most ~500 USD IEMS out there, but they also do it while being thick and heavy, not analytical or bright. A good song to study the midrange of the Carbon is Demondice – Sick Outta Fashion, a pretty classical rap song. Karen’s voice is sweet and has a natural tonality, while the bassline has a frontal position and leads every other instrument, giving the whole song groove and a wide presentation, with a clean background. Another favorite artist to test the midrange is YFU Baby, and her song YABAI is perfect for this, because it has a strong bassline that has superb fullness thanks to the longer decay and high amounts of bass in the Carbon’s sound, plus the song has a super sweet voicing for YFU’s voice, and a lot of detail in general. 



The treble of Carbon is actually fairly bright and emphasized, to create balance for the strong and full bass. The treble provides the much needed sparkle and detail for the sonics, along with air to the sound. Most of the energy in the treble is in the upper midrange – lower treble zone, so the treble can be hot, especially with brighter recordings, which is part of the reason I stated earlier that Carbon sounds best at medium and lower volumes, and can be aggressive at super high volumes. Songs like ChuggaBoom – Bohemian Rhapsody are perfect to notice this. Piano strokes are super clean and have zero distortion, and the perfect upper midrange volume to have an emotional sound, but guitars and especially cymbals can be fairly strong and bold, which is expected from this song in particular. Other songs from ChuggaBoom, like Ohana Means Family, do not have such a strong treble, and are easily listenable at high volumes, so it is safe to say that Carbon is revealing of the original recording quality.







Periodic Audio Carbon vs Earsonics Onyx (500 USD vs 560 USD) – Onyx is much more mid centric than Carbon, and also larger in size and design. The comfort will be a bit better on the Carbon, and it comes with more tips and a wider selection of accessories. The overall sonic presentation has much more bass extension, better depth, more impact and bass volume, everything sounds fuller, chunkier, darker and more lush on the Carbon, while it sounds more open, more natural, cleaner and wider on the Onyx. Onyx is perfect for you if you enjoy a Grado signature, it sounds like a high-end Grado headphone, while the Carbon is a thick, lush and deep experience with tons of lows and incredible impact. 


Periodic Audio Carbon vs IMR Acoustics Ozar (500 USD vs 500 USD) – Ozar is actually known for Bass, and IMR Acoustics generally has superb bass and treble quality for their IEMs, so it is fair to state from the start that both IEMs do well with heavy basslines, and both have tons of impact. The sound is much more configurable on the Ozar, thanks to their design that has many filters and can be configured. The overall comfort is better on the Carbon, as it is smaller and lighter, but Ozar comes with balanced cables in the package, and with more cables, which feel more resilient, but are heavier. The overall sonics are heavy and V-Shaped on both IEMS, and I like both with the same music, they are direct competitors. Carbon has slightly more bass quantity and fullness, and a stronger upper midrange / lower treble, being more aggressively V-Shaped than Ozar is at its maximum V-Shaped configuration. The maximum detail is comparable, and the stage is wider on Ozar. I would go for Crabon if you find that comfort is generally problematic for you, while Ozar can provide more stage, and a slightly less bass and treble, but for the cost of comfort, as Carbon is smaller and the tips seem to work a bit better with my ears. 


Periodic Audio Carbon vs Campfire Audio Holocene (500 USD vs 650 USD) – Holocene is an IEM that is considerably lighter sounding than Carbon, because it has much less bass quantity, but the overall treble is not quite as aggressive as the one on Carbon, and it is easy to enjoy the Holocene at louder volumes, even with albums that are somewhat distorted and not so great in mixing / mastering, while Carbon tends to reveal the quality of the original recording / mixing / mastering a bit more. Holocene is slightly more sensitive to source quality, and the Carbon needs more power to sound loud. The decision here is rather simple, if you love a fat, thick bassline, Carbon is the one for you, while if you prefer a lighter, more natural overall sonic presentation, Holocene is the one to go for. The comfort is great on both, Carbon allows for straight-down and over-the-ear wearing, while Holocene just over-the-ear, but Holocene has a more common MMCX standard (for IEMs). 




Value and Conclusion


Priced at 500 USD, Periodic Audio Carbon has a superb price / performance ratio, as long as you’re a basshead. The kind of full, smooth and impactful bass lines such tiny and lightweight, comfortable IEMs are able to deliver. The overall package is also good, they come with a tiny, but effective case, and now have a detachable cable with a pretty common 2.5mm connector. 



Allowing for over-the-ear wearing, to fully eliminate microphonic noise, and having a super flexible cable, along with a lightweight, but ergonomic shape, Periodic Audio C Carbon is super user-friendly, and they allow straight-down wearing, being the kind of IEMs that you could recommend to basically anyone, especially if you’re a basshead or recently discovered that they have a bass kink. In fact, I like the Carbon so much that I will be adding it to Audiophile-Heaven’s Hall Of Fame as an easy purchase for bassheads in the 500 USD price range. 



At the end of the day, Periodic Audio Carbon is the perfect IEM to recommend to anyone looking for a high quality, lightweight, heavy-hitting, full-sounding, detailed and clean IEM with detachable cables for 500 USD. 




Product Link


You can grab one from www.amazon.com here: https://amzn.to/3JMy4cK


If you’re in the UK, you can grab one from www.amazon.co.uk here: https://amzn.to/3uEPqUK




And if you’re from Europe, you can grab one from www.amazon.de here: https://amzn.to/3JDBM8t







— Please remember to stay safe, and always have fun while listening to music!—







Full Playlist used for this review


We listened to more songs than those named in this playlist, but those are excellent for identifying a sonic signature.  PRaT, Texturization, Detail, Resolution, Dynamics, Impact, and overall tonality are all revealed by those songs. We recommend trying most of the songs from this playlist, especially if you’re searching for new music!


If you have a dime to spare (donate), it would make my day much brighter, as it would help me improve things around the website and increase the frequency of my posts.


Youtube Playlist



Tidal Playlist






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1 Comment

  1. Man, can’t wait to read your input on all the other mdoels as well! Love your works, and love those IEMs, thank you so much for all your effort for bringing something of quality to the public!

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