Dynamic Ear Company’s ambient filters: the audiophile’s perspective

Continue reading Dynamic Ear Company’s ambient filters: the audiophile’s perspective

Knowles, industry leader in BA design and production, teaches us about IEM design & tuning

Andrew Bellavia (Twitter) of Knowles Corporation gave a talk at AES@NAMM 2018 last month on the 27th of January and went into depth about the acoustic science behind in-ear monitors and multiple balanced armature acoustic design.
Continue reading Knowles, industry leader in BA design and production, teaches us about IEM design & tuning

Critical Analysis: 1964|ADEL — Science or Science Fiction?

Editor’s Note: At CYMBACAVUM, we’re constantly trying to bridge science with the wonderful audio experiences we have. @miceblue takes on an scientist’s curiosity to examine Asius Technologies and 1964Ears’ ADEL — how it functions, the scientific principles behind it, and what it might or might not be. Continue reading Critical Analysis: 1964|ADEL — Science or Science Fiction?

LIFE Acoustics & Kickstarter

Editor’s Note: We tend to publish in bursts. That’s just the way it works when none of us on the writing roster does this for a living — we write when we can, and all of us do it essentially on a volunteer basis. Not having much activity in between these bursts doesn’t mean we’re not working behind the scenes. After all, CYMBACAVUM is not purely a review platform; we seek not only to identify folks doing good work within the audio community, but also to push for ever better standards of performance. We may never be the first to “review” something, but we always strive to be the most insightful.
Continue reading LIFE Acoustics & Kickstarter

LH Labs Verb: Indefensibly Bad

LH Labs, a subsidiary of ultra high-end audio company Light Harmonic (maker of the $20,000 Da Vinci DAC), has wafted massive ripples across the personal audio industry over the last couple of years. With their seminal Kickstarter campaign for the pocket-sized DAC/amp the Geek Out, they popularized crowdfunding as a viable option for audiophile products, spurring a bunch of follow-up campaigns in the Geek Pulse and Geek Wave, as well as campaigns by other companies. Continue reading LH Labs Verb: Indefensibly Bad

Electroacoustic Measurements from speakerphone

Editor’s Announcement: Ladies and gentlemen, we have great news to announce — CYMBACAVUM will now provide in-house acoustic measurements!

Our newest contributor is speakerphone; he has been running his own acoustic measurement blog, http://clarityfidelity.blogspot.kr/, but will be partnering with us to deliver measurement results on select items featured on this website. Occasionally, he will also be delivering commentary regarding measurement results and products. As a modest guy, speakerphone claims that his English isn’t that good and is reticent to provide opinion pieces, but Mr. T thinks otherwise and will be encouraging him to open up with thoughts!

We believe speakerphone is an invaluable addition to the CYMBACAVUM team and will help enrich readers’ experience by helping us correlate our perceptual experience with data sets comparable across products. His measurement methodology is finely tuned to comply all current international standards of information for the measurement of headphones and earphones, as well as recent developments and revelations in headphone acoustic research.

The following details protocol to be followed in all forthcoming electroacoustic measurements:


All posted measurements, unless otherwise noted, ​will comply with IEC 60318-4 (formerly IEC 60711), ITU-T Recommendation P.57, and ANSI S3.25 standards for artificial ears.​

Measurement Acquisition

Acquisition follows a modified IEC 60268-7 standard, with ~0 Ω output impedance (instead of 120 Ω) for the output amplifier (NwAvGuy’s O2 headphone amplifier). The modified standard is used to better suit low input impedance devices, such as the IEMs and other earphones being measured. For reference, both Knowles and Sonion also qualify their balanced armature receivers with output amplifiers possessing ~0 Ω output impedance.

For frequency response analysis, the source signal is pink periodic noise (smoothed 1/24th of an octave). For harmonic distortion analysis, the source signal is stepped sine (1/6 octave increments).

Unless otherwise noted, unprocessed data points obtained from frequency response analysis will further apply the following compensation models:

  • Diffuse Field Target, following the ISO 11904-2 standard (indicated only from 20 – 10,000 Hz), with a 10,000 – 20,000 Hz extension at -6 dB/octave
  • Olive-Welti In-Room Target (Olive, Sean; Welti, Todd; McMullin, Elisabeth at AES), from acoustic research at Harman International.


  • IEC 60318-4 : Electroacoustics – Simulators of human head and ear – Part 4: Occluded-ear simulator for the measurement of earphones coupled to the ear by means of ear inserts [Link]
  • ITU-T Rec. P.57 : Series P: Telephone transmission quality, Objective measuring apparatus : artificial ears [Link]
  • IEC 60268-7 : Corrigendum 1- Sound system equipment – Part 7: Headphones and earphones [Link]
  • ISO 11904-2 : Determination of sound immission from sound sources placed close to the ear [Link]
  • ​Olive-Welti Target : Listener Preferences for In-Room Loudspeaker and Headphone Target Responses [Link]

The Biz: What companies make Balanced Armature Speakers?

Legal Disclaimer: All information produced in this article has been obtained through publicly accessible means. CYMBACAVUM and its editors and writers, have not been privy to nor have disclosed any confidential information.

There are countless manufacturers for dynamic coil speakers in earphones. However, due to their miniature size, the number of balanced armature receiver makers is far lower. In the past, the market for BA manufacture has been (and still is) dominated by two companies: Knowles and Sonion. However, as the market for in-ear earphones has expanded, global demand for “premium sound” has propelled more and more companies to get into the game for manufacturing balanced armature drivers. While both Sonion and Knowles continue to dominate, earphones using balanced armatures in the future might not necessarily use their products.

So without further ado, here is a posting of the fruits of our labor… (in no particular order) Continue reading The Biz: What companies make Balanced Armature Speakers?