Planar Bass from Out of Space!

PROS: dual Planar Magnetic driver design (14mm and 6mm), rich sound texture, powerful bass, hi-res treble, fast dynamic sound, comfortable lightweight shells, two Time Stream cables included (3.5mm and 4.4mm), and other custom accessories.

CONS:  very noticeable sound dependency on eartips and source selection.

The product was provided to me free of charge for review purposes in exchange for my honest opinion.

Manufacturer website:  CFA.  Available for sale from authorized retailers like Musicteck and Bloom Audio.

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Intro.

Two years ago, when Campfire Audio introduced its first Planar Magnetic driver Supermoon, many audiophiles were caught by surprise since CFA is better known for perfecting IEMs with DD and BA drivers.  According to Ken Ball, the founder of Campfire Audio, while attending many global audio shows, they are often approached by various transducer manufacturers.  That is how they came across custom subminiature planar drivers implemented in Supermoon and later in Moon Rover.  Staying true to their outside-the-box thinking instead of following other popular EST and Bone Conduction drivers’ trends, CFA continued exploring new planar driver ideas, arriving at their latest creation of dual Planar Magnetic driver Astrolith.

As a fan of Supermoon which I have reviewed before, the announcement of Astrolith (Astro) caught my attention, but after reading several reviews and impressions, I found a bit of a discrepancy in its sound description.  That made me even more curious about the role of different sources and how they affect the pair-up synergy and sound tuning of Astro.  When the opportunity knocked on my door to review this latest CFA release, I decided to go for it and… became addicted to their tuning!  I have been listening to Astro for a few weeks now, spending more time enjoying the music rather than analyzing the sound.  Finally, I was able to finish my review and would like to share with my readers what I have found.

Unboxing and Accessories.

I find the unboxing of any CFA product to be a very satisfying experience filled with many surprises.  The compact box Astro arrived in was covered in artwork that reminded me of old-school comic books, including lots of useful info all around it on the outside and inside.  It’s an environmentally safe cardboard box you can recycle, but I doubt anybody would do that considering how fun it looks, just like a collectible comic book.  In fact, after removing the contents of the box, I took my time to examine it inside-out before getting to the included goodies.

In there, along with a pair of Astro IEMs, you will find CFA’s silver-plated copper Time Stream cable in both 3.5mm and 4.4mm terminations.  There was also a custom Black Dimensional Folding leather case with magnetic closure and a small aluminum carabiner clip.  This soft premium leather flat case looks and feels like an elegant wallet, and is quite functional to carry your IEMs and cable.  Of course, it could be used to carry other things in style as well.

There is also a two-pocket soft mesh IEM protector bag with a drawstring in bronze color which CFA refers to as Breezy Bag Micro.  Along with it, there was a matching bronze color mesh Breezy Bag Jr. bag with a zipper and removable shoelace string attached with clips to wear it over the shoulder.  The accessory bag was compact and still roomy enough to carry IEMs with a cable, and maybe extra cable and spare eartips.  I have to admit, I wouldn’t mind at all wearing this breezy zippered bag as a “man purse” 🙂

Also included were two sets of eartips, one was Marshmallow foam tips (in S/M/L sizes) and another one was Silicone tips (in S/M/L sizes).  There was also a traditional earphone cleaning tool, a cleaning cloth, and an exclusive Campfire Audio lapel pin.

Cable.

You can find Time Stream cable with some of the other premium CFA releases.  This cable uses 4 separate enameled silver-plated copper conductors encased in individual “non-migratory” PVC jackets.  This custom soft non-microphonic cable stands out with a unique ribbon design where each wire is isolated to reduce crosstalk, interference, and noise coupling.  The cable features silver metal hardware with a matching plug, flat y-split to accommodate the ribbon design of 4 conductors on one side and a pair of 2 conductors above the split, clear plastic chin-slider to accommodate the ribbon design as well, and compact housing mmcx connectors.

Yes, CFA still features mmcx connectors, but these are custom-made of copper and beryllium materials to ensure durability and longevity and feature a very secure snap-on design.  Another thing to note, CFA offers their Time Stream cable in 3.5mm, 2.5mm, and 4.4mm connectors, separate cables with individual fixed terminations instead of a modular plug design.  Astro came with 2 separate cables, 3.5mm SE and 4.4mm BAL terminated.

Design.

In the heart of Astro, you will find 2 Planar Magnetic drivers, a 14mm (14.2mm to be precise per CFA product description page reference) driver for lows and mids, and a 6mm driver for high-frequencies.  As far as I can tell, for now, this is the first and only compact IEM featuring two separate custom Planar Magnetic drivers in a crossoverless design.  While these don’t require a crossover to shape their tuning like in many other multi-driver IEMs, CFA implemented custom acoustic chamber tuning elements for each driver.

The new high-frequency 6mm Planar tweeter is wrapped in a custom Particle Phase Resonator (PPR) tuning chamber to shape its high-resolution sound. The next-gen 14mm Planar, which covers low/mid frequencies and features refined mechanics and updated grille patterning (relative to the original 14mm Planar in Supermoon), has its sound shaped by a new Additive Acoustic Optical Inclusion (AAOI) housing along with a unique front choke damper element.  These chambers are carefully engineered to create precisely controlled acoustic volumes that affect the performance of both drivers as their sound blends in.

Astro’s shell is relatively lightweight, surprisingly compact, and quite comfortable to wear.  It has a 3D-printed polymer body and a full CNC billet mirror-finish polished stainless steel faceplate and nozzle with pre-drilled holes.  The faceplate has a cool modern art design with a layered stepped effect and an etched CA logo.  The polymer body of the shell has limited transparency, allowing you to see the outline of internal chambers as you bring these closer to the light and rotate to catch the view.  And as expected, you will find a solid-build mmcx connector socket.

The fit.

Page 2 – Sound Analysis, Eartips selection, and Cable pair up.
Page 3 – Comparison, Source Pair up, and Conclusion.