Disclaimer: The Billie Jean by Astell&Kern was sent to me free of charge for this review. It does not have to be returned. Astell&Kern is not affiliated with Headfonia and not a site advertiser. Many thanks for the generosity and opportunity!
Astell&Kern is a South Korean high end brand for digital audio players (DAPs). Astell&Kern is a branch of Korea’s iRiver, which actually is the first company to ever build a portable audio player. Astell&Kern was launched with the mission to offer the absolute best where money is no object. Ever since their launch, they have redefined what is possible from portable devices. With the AK100 they introduced their first product in 2013 under the A&K brand.
Astell&Kern has pioneered a few things we know of today. They were the first to build a DAP with two DAC chips inside – AK120. AK was the first brand ever to introduce native DSD playback in a portable device – AK240. The AK380 was the first ever digital audio player that came with a Parametric Equalizer.
Just recently AK has introduced what they call Teraton. This is an audio module that contains their digital and analogue design. This module can be implemented by third party brands in order to get closer to the AK sound. The first product has already been released that utilizes Teraton – the Activo CT10.
AK also cooperates with many other industry leading brands. In partnership with brands like Beyerdynamic, Final Audio, Jerry Harvey Audio or Crystal Cable, Astell&kern has brought out many different products under their name. Together with JH Audio they have released a good number of different universal In Ear Monitors. The most recent being today’s review’s guest of honour – the Billie Jean.
About Billie Jean:
The Billie Jean is a dual BA monitor that uses a single BA for bass/mids and a single BA for highs. It is part of the Siren Series by Jerry Harvey Audio, under which also products such as the Angie or Layla have been introduced. Billie Jean also features the patent pending Freqphase Time | Phase Wave Guide. Which is said to cancel out any phase inconsistencies for a more harmonic sound. Here’s a video of Jerry Harvey explaining it in more detail:
The Billie Jean is also the first JH Audio product to come with an acoustic chamber introduced in the nozzle. This chamber is located after the opening of the sound bores and offers a small chamber for the sound to be optimized.
Billie Jean is available in two colours, red and blue. It’s impedance is measured at 18 Ohms, there is no information about frequency response or sensitivity. Though I must say, that the Billie Jean to me seems like a rather sensitive monitor, as it is fairly easy to drive to loud listening levels (not advised of course). It also picks up noticeable noise from my Chord Hugo2.
Billie Jean is available for 349$ at your local Astell&Kern shop. If there’s none in your country, you may consult Astell&Kern’s online shop.
Here is another video by Jerry Harvey where he discusses the birth of Billie Jean:
The review continues on page 2!