The Periodic Audio website leads with "Masters of Sound." Its Twitter handle reads "Mobile First Hi-Fi," and the high-end audio outfit wants to put "a high-end audio system in everyone's pocket."

Those are bold claims, and if it sounds ambitious, that's because Periodic Audio has come a long way since its 2016 launch, producing exceptional audio hardware crafted with premium materials. Each IEM bears the name of the material used to craft its drivers.

The Periodic Audio Carbon IEMs are what you might expect from a set of in-ear monitors: soaring bass, wonderfully clear and accurate mids, and a delicate top-end that lets any music shine through.

In short, the Periodic Audio Carbon IEMs are fantastically fun, beautifully detailed, and are perhaps some of the nicest IEMs I've had the pleasure of plugging in with. If that sounds intriguing, keep reading for our full Periodic Audio Carbon IEM review.

Periodic Audio Carbon Features

One of the most interesting things about Periodic Audio is their attention to detail. Everything inside each of Periodic's IEMs is built in-house, and the company has a strong understanding of applied materials science that translates through to their products. The Carbon IEM "utilizes a lab-grown diamond layer (8 microns) on our own proprietary high-temperature polymer substrate," which translates to a completely unique bit of driver hardware.

The Periodic Audio Carbon IEMs under review aren't the first iteration of these earbuds, either, so this latest generation comes with further refinement than those that came before (along with detachable cables).

Interestingly, the build quality of the Carbon IEMs doesn't feel luxurious. You'd be forgiven for mistaking them for a regular set of wired buds, the Carbon's relatively simplistic design hiding the audio goodies found inside the barrel-style copolyester thermoplastic. However, despite the unglamorous aesthetic, they feel solid, and that the exterior casing will protect the inner workings. Given the manufacturing material is used in plenty of other high-stress products, it's safe to say the Carbon IEMs are well protected.

As above, the new Carbon version comes with one of the most requested features: detachable and replaceable cables. Where the previous version used an integrated design, the Carbon now has a 3.5mm TRS to dual 2.5mm TS jack cable, meaning if the cable or jack breaks at any point, you can easily swap it out. Plus one for sustainability, then. The 2.5 TS jack (which the company calls IDEEL—IEM Direct Electrical Engagement Link) is also of Periodic Audio's own creation, measuring just 3.6mm across and minute 9.5mm mounting depth.

In the box, you'll also find multiple ear tips, a handy gold-plated airline adapter, a 6.35mm TRS adapter jack, and the exceedingly useful protective carry case. As ever with any earbuds, take the time to swap the ear tips around and find the right fit for your ears. It makes a huge difference to how you'll experience the earbuds.

Periodic Audio Carbon Sound Quality

Periodic Audio's attention to detail translates to the audio experience, as you might expect. Plugging in and listening to music with the Carbon IEMs is, simply put, outstanding. No matter what music you turn to, it sounds excellent, pushing me towards the end of my list of superlatives.

The biggest difference you'll note when switching between your regular headphones or earbuds to something like the Periodic Audio Carbon IEMs is clarity. Every single part of each track you listen to sounds like you're hearing it individually. The mixing for each layer comes through crystal clear, and you'll begin to hear different parts of tracks you've listened to already.

Compared to "standard" headphones or earbuds, the balanced, unimpeded sound is brilliant. These IEMs aren't completely flat, as you might find with other IEMs, but the slight tuning is what makes the Periodic Audio Carbon sound so good.

Putting the Carbon IEMs to test Pink Floyd's Shine On You Crazy Diamond, and you're whirled through a masterpiece of composition, with each of the nine parts delivered with beautiful clarity, the guitar strings resonating as if you were there in the studio. Switching up to Aphex Twin's Windowlicker, which is something with faster, punchier transitions across a wide frequency range, and the Carbon is again excellent. The subtleties of the track shine through, and you hear each different layer of the track as clear as it was designed, particularly during the heavier transition phases towards the end.

The Carbon IEMs deal with complex arrangements with ease, too. Michael Jackon's Beat It is rattled out with precision, each vocal layer remaining clear and accurate throughout the entire track. Steve Reich's Music For 18 Musicians is another excellent option, the growing cascade of instruments harmonizing wonderfully, the Carbon IEMs ensuring that the complex structure of the piece remains easy to follow in and out of its pulsing twists and turns.

Describing how music sounds through a set of headphones is always an interesting task. With the Periodic Audio Carbon IEMs, the most important word is clarity. Everything you play through these IEMs sounds exceptionally clear, and the craftmanship of Periodic Audio shines through again and again.

Periodic Audio Nickel Amp

We've also had the pleasure of testing the Periodic Audio Nickel Amp alongside the Carbon IEMs. The Nickel Amp is a tiny, battery-powered amp that fits in your pocket yet delivers a surprisingly big boost to your listening experience. It delivers a fixed gain of 6dB, which isn't heaps, yet the clarity that it delivers that boost with is most impressive.

While the Periodic Audio Nickel Amp was supplied with the Carbon IEMs, it's worth noting that this pocket-sized amp will work with any wired earbuds or headphones, providing a tidy boost for any bit of audio you have. And it's powerful, too. Don't let the fixed gain rating trick you; this amp is rated for 250mW per channel.

The Nickel Amp is battery-powered, too. Like the Carbon, this is the second iteration of the Nickel, and it has a larger, 400mAh battery (versus the 220mAh original) that will keep going for hours at a time. It charges fast, gaining a full charge in just 30 minutes or so.

Placing the Nickel Amp between my smartphone and the Carbon IEMs does make a difference to the audio output. Overall, using the Nickel Amp appears to deliver more detail, another level of audio, perhaps elevating the full frequency response in such a way that it will benefit almost any set of headphones or earbuds you care to use it with. In that, the Nickel Amp is interesting, as it is a portable, battery-powered amp that will make any headphones or earbuds sound better, yet it's likely only going to be the most ardent audiophiles that buy such a piece of audio hardware.

Should You Buy the Periodic Audio Carbon IEMs?

These are exceptional IEMs. There are no two ways about it. The Periodic Audio Carbon IEMs sound sublime, and heading back to other earbuds and headphones after using these is tricky.

If you have the money and you want an exceptional audiophile experience, these are the IEMs for you.

On that, the Periodic Audio Carbon retail for $499, which is what will really decide whether you go for these or not. Not everyone needs a 500 buck set of IEMs, and not everyone will even feel or realize the difference they make to your listening experience.

It's not like when you buy a set of wireless earbuds with a companion app and a customizable EQ and all the other gizmos and doodads that come in the package. Also, consider that while these exceptional IEMs are brilliant for walking around or sitting at your desk listening to music, they're not what you need if you want to go running or use them for other activities. These are very much for enjoyment, immersing yourself in the musical experience, eschewing the outside world to take in the audio.

When you buy a Periodic Audio IEM, you're buying a complete audio product, crafted to excellence. So, what I can say, is that if you do decide to buy these incredible IEMs, you won't regret it. Not for one minute.