Secrets of Home Theater and High Fidelity - Best of Awards 2020


Marketed as simple yet precise, the Periodic Audio Beryllium IEMs provide a high-quality audio experience with no unnecessary fluff or frills.

Periodic Audio Beryllium In-Ear Monitor Review


Periodic Audio Beryllium In-Ear Monitor

  • An appealing, utilitarian look
  • Durable and light polycarbonate body
  • Tried and true Bullet style design
  • Balanced and full sound quality
  • Excellent in-ear fit

Periodic Audio Beryllium In-Ear Monitor

When it comes to my preferred listening experience, I lean towards in-ear monitors. Their convenience makes them the most readily available means of listening to music. So, when my father arrived back from Rocky Mountain Audio Fest with a pair of Periodic Audio’s Be (Beryllium) earbuds for me to review, I happily made the switch from my slightly less upmarket pair of in-ears. Immediately, I was attracted by the bullet design, which seems to be less and less preferable among IEM designers these days. I prefer the simpler approach; I’ve never liked having the wire wrap around my ear. After a good length of time using these on the regular, I’m prepared to assess how the Periodics stood up during extended use.

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Frequency Response:

12 Hz to 45 kHz


32 Ohms nominal


100 dB SPL at 1mW in ear

Power Handling:

200 mW continuous

Peak SPL:

123 dB


Less than 1% THD at 1mW

Cable Length:

1.5 m


2.8 / 9.3 g (IEM/Set)

Overall Length:

21 mm

Body Diameter:

12 mm

Nozzle Diameter:

6 mm


Black with gold end cap


6 pairs of silicone ear tips, 3 pairs of memory foam ear tips, ¼” phono adaptor, airline adaptor, metal carry case.


5 years




Periodic Audio


periodic, beryllium, iem, bullet, Earphones Review 2019


Periodic Audio Beryllium In-Ear Monitor Set

Periodic Audio Beryllium In-Ear Monitor Case

Periodic Audio refrains from smothering these IEMs in unnecessary detail or gaudy bells and whistles. They stick to a simple black polycarbonate shell, black cable, and plain bullet-shaped design. They are fairly sized, with a 21 mm length and a 12 mm diameter. Each enclosure has dual ports which Periodic claims extend the bandwidth of the BE and reduce diaphragm motion over a two-octave range. The only hint at the slightly higher price tag is the gold cap on the back that bears an embossed logo. Mind you, that end cap isn’t simply there for aesthetics. According to Periodic’s literature: “It is a counterbalance. The counterbalance sets the center of gravity perfectly to avoid pressure on your Tragus, and/or Anti-Tragus, as these are the areas you’ll notice pain after extended IEM use.” Beyond this, the product looks fairly standard, which is not a bad thing. There is no in-line play/pause button on the wire. Periodic Audio seems to have distilled these to the most fundamental parts, filtering out anything not needed. I don’t like overly flashy things, so this suits my tastes very well.

Periodic Audio Beryllium In-Ear Monitor Closeup

Periodic Audio Beryllium In-Ear Monitor In Hand

The slightly plain outside does not indicate a lack of quality, however; the driver held within has a pure beryllium foil diaphragm, which is the source of the Be’s namesake. Periodic Audio states that this material choice “results in high efficiency and extremely low distortion.” The aforementioned polycarbonate shell ensures a design that is lightweight with high durability and low resonance. These IEMs manage to combine the worlds of high quality and low profile, creating an experience that is consistently enjoyable without the annoyance of overly ornate earbuds. In place of the typical monogrammed L and R to indicate the respective listening channel, the Periodic Be have driver grilles that are colored red and black to identify themselves.

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Included with the Be’s is a small metal, screw-top carrying case, 6 pairs of silicone tips, 3 pairs of foam tips, a 1/4” phono plug adapter and an airplane adapter. It’s worth mentioning that the case is very light and compact making it convenient to keep in the pocket or carry in a bag.


I used these earbuds with my Samsung Galaxy S10, switching between Spotify streaming and listening to FLAC files that I had saved locally. Upon initially putting these earbuds in, I noticed the seal that the units formed in my ear. It was tight, but not so tight that it was uncomfortable. Throughout my use of the Periodic Be’s, the seal sat squarely in the sweet spot of strength and comfort with no need to switch tips out. The earbuds are comfortable in use and out; despite my decision to refrain from using the carrying case, the earbuds never caused me discomfort while I was carrying them. I enjoyed their low profile nature, as well as their convenience and power.

In Use

When the Beryllium earbuds get to stretch their legs, they make the full extent of their quality known. They flourish a balanced sound, melding highs, mids, and lows in a way that ensures they all cooperate; no one has the spotlight and no one is left out. The sound is crisp, full, and void of any strange echos or other unwelcome phenomena. The goal of the Be’s is precise sound, and they deliver exactly that. The Be’s filter out outside noise very nicely as a result of the excellent seal, and beyond that the sound that they deliver is clean, tight, and full. Deep lows set up a foundation for the strong mids, and the highs pierce through just enough to make their presence known, but not enough to grate. Each aspect knows its place and function and executes them in cooperation with one another, creating a formidable sound that more than justifies the price tag. Throughout my test period, the Be’s created an immersive experience by directing my focus to the music itself. I felt no need to adjust the volume in an unorthodox fashion; my usual listening levels transferred perfectly well.

My only concern in the Be’s is their ability to stand up to rough use. Not the IEMs themselves, but the wire that holds them together. It stood out to me that the cable seemed flimsy and slightly weak, and I tend to be fairly aggressive when untangling my earbuds. It doesn’t seem impossible to me that someone ends up spoiling these rather nice earbuds by busting the wire when they’re unpacking them in a hurry. I never experienced any issues with the wire deteriorating during my trial run, but it did seem rather strained at certain points.

Soul Burn

Dealer “Soul Burn”

Australian hardcore supergroup Dealer made an explosive debut earlier this year with their Soul Burn EP. The band makes it immediately clear that they do not want there to be any nonsense, as the six-track package stays compelling and aggressive from start to finish (with a small moment of reprieve during “You in Frame”).

Squealing, chugging guitars and a startlingly sharp vocal performance spell an introduction that is bound to make an impact. The EP certainly made an impression during my time with it, as the Berylliums’ balanced sound allowed the full spread of Dealer’s aggression to become startlingly apparent and poignant, without one end of the sound ruling over the rest.

Weeping Choir

Full of Hell “Weeping Choir”

Full of Hell’s sinister menagerie of grinding anger was given another outlet on Weeping Choir, a follow up to their 2017 effort, Trumpeting Ecstasy. From start to finish, the blast-beats and walls of noise batter the listener from all directions, and these macabre howlings make use of the full breadth of the Be’s power.

Full of Hell is among the most extreme acts to surface in recent years, and their chaotic churnings, while being an obstacle to some, also compel others in a strange way that is almost impossible to understand. In conjunction with Periodic Audio’s IEMs, Weeping Choir swept through the Beryllium drivers and kept my head moving.


Portal “ION”

The mysterious collective of entities known as Portal unleashed the album Ion in early 2018. The true nature of this confusing, oxymoronic collection of sounds still eludes the metal community, but it is universally regarded as a landmark album that consistently warps the mind.

Portal’s enigmatic songwriting, like the other albums sampled with the Be’s, makes extensive use of all slack that the IEMs can provide, commanding brutally heavy bass tones with chaotically fast guitars and haunting whispers, meaning that Ion is not suitable for everyone. Again, however, it shares a trait with the former two albums in that those who can stomach the whirling chaos of Portal are rewarded with an unnaturally compelling experience. The earbuds performed well during the recitation of this album, delivering the eclectic sounds with balance, impact, and precision.



The PERIODIC AUDIO BERYLLIUM IEMS are a simple, high-quality product that provides the consumer with an exceptional listening experience. I’d consider them almost a necessity.

  • High playback quality
  • simple design
  • excellent seal
Would Like To See
  • A slightly more robust wire

My time with the Berylliums was thoroughly enjoyable, and I consistently looked forward to using them when I listened to my music. I find the simple design aesthetic appealing and noted an exceptionally balanced and full sound across the spectrum. After all is said and done, the Periodic Audio Beryllium IEMs are a set of earbuds that are worth the $300.00 price tag. Just don’t be too quick to judge a book by its cover. Their simple, unassuming design may not look the part, but they sure as hell sound it. An ultimate stealth product and highly recommended.