Moondrop Solis

disclaimer:  I was sent the Solis and Illumination for review as part of the lending library from Moondrop Labs.  I have received no compensation for this review, nor was either in-ear given to me for the purpose of these reviews.  If anything, I lost roughly $50 on postage and insurance costs.    If  you have an interest in Moondrop products, Please see their website or facebook page for more information.  To purchase moondrop products, visit your favorite reseller.

 

Unboxing / Packaging:

I received both the Illumination and the Solis in their soft cases with a few extra tips and alcohol preps for cleaning them up as these are tour sample units.   For that reason, I am forgoing the unboxing notes as these two were far from retail packaging and already well traveled by the time they arrived in my possession.  One was even missing some of the tips so I can’t speak to the accessories that come in the retail packaging.

 

Build/Fit:

The Solis is a handmade model with a two part shell consisting of an outer faceplate and an inner shell/nozzle assembly in the now familiar semi-custom style inverted teardrop shape.   The shells are resin throughout including the nozzles and are mid-sized so should not present a fit issue for all but the smallest ears.   Face plates have gold dust and a gold emblem of the sun surrounded by dragons (my guess) while the inner shell is solid black in color.   A clear version is also offered and shown below in the internals discussion.   Nozzles have a distinct forward offset so sit largely in front of the body when in ear which somewhat limits isolation as the bulk of the body sits behind the ear canal.   Nozzles have 3 sound bores but no lip for tip retention although this was not an issue during my testing.    The bi-pin connector is well fitted with no glue showing and it not even found by a fingernail dragged over it so polish is up to a very high standard on these shells.   I had no issues wearing the Solis for an extended period and found that quite comfortable for long wear.

 

Internals:

The Solis has a lot going on internally with 4 balanced armatures per ear and a pair of electret driver on top of that.    The bass drivers are a Sonion 37 series dual armature package that houses two drivers and a shared expansion chamber.  Mids are handled by a pair of Softears D-Mid-A drivers and highs by a pair of Sonion EST.   Some refer to these as electrostatics but truth be known they are more closely related to the older electret drivers than to the electrostatics used in things like Stax headphones.    Having said that, the stated goal of the tuning of the Solis was to match the sound of the Stax 009 in an in-ear (pretty lofty goal).     These are markedly easier to drive than any of the over-ear electrostatics with a nominal impedance of 7.5Ω and a sensitivity of 120 dB/mW.   I found these were well driven by my LG phone in high-output mode, but did scale well and improved both qualitatively and quantitatively with better sources.

Cable:

The provided cable uses a 3.5mm 90º jack in a translucent housing before a 4 wire braid of copper wire in a clear coating exits.   The splitter is the standard Moondrop coin style in black before two wire twists exit above.   The twist above the splitter is tighter than the braid below which creates an interesting contrast.  The north end terminates with earhooks without memory wire and .78mm bi-pin connectors in housings that match the jack stylistically.    This makes the markings for left and right quite difficult to find and a red dot on one side would be a appreciated but is not present.   The cable wears well, has good pliability, and  doesn’t transmit movement to the ears so it does a good job although I cant escape the thought that the quality of the cable may not quite equal the iem itself.

 

Sound:

Bass:

The Solis has a very typical balanced armature sub-bass with notable roll-off below about 40Hz and a bit less slam and rumble than will please bassheads.  What is there is clean, fast, and has some texture so it is hard to call it poor, it just is not emphasized.  Those looking for a big sub-bass punch wont find it here.   Mid-bass is more emphasized comparatively, but still remains in good proportion to the rest of the signature with the mid-bass and mids being very linear.   Bass textures are good with fast attack and decay and again as expected from the armatures, decay is slightly too fast to be wholly natural.    The Sonion 37 comes as close to natural tone as I’ve heard in a bass armature which gives me hope, but there is still progress to be made.

 

Mids:

The transition from the mid-bass to lower-mids is very clean with no bleed or missteps.  Male vocals have good weight and tone and manage to cut through the instrumentation well enough to be convincing.   Guitar growl is quite good with sharp edges and enough rasp to the tone to feel a bit ragged where it should.   Strings have good energy as well with String quartet pieces being well voiced in both lower and higher registers which is a nice surprise.   Female vocals are mildly forward of their male counterparts but what emphasis is there is mild and if anything when fed tracks that are harsh to begin with, you get the sense of a little smoothing to the sound as there is no tendency to fatigue or sibilance here.    (This is a surprise between BA mids and the Electrostat top end).

 

Treble:

Lower treble shares the small emphasis of the upper-mids but I have to say those who have tried the Sonion electrostat driver before and expect a really sizzling treble will be pleasantly surprised here.  I had not heard this good an implementation of the stat to date and applaud Moondrop for a tuning that gives great extension without being overly hot and forward in the process.   Matter of fact, if you didn’t read the documentation, you’d be forgiven for thinking the Solis packed one of Sonions top-end armatures as the sound has lots of detail and air without getting overly bright or harsh.    If anything, I think the Solis could use a touch more energy  as snare rattle seems a bit muted and smoothed and cymbals also need a bit more in the 6-8kHz range to be completely natural, but that is nitpicking at best.

 

Soundstage / Imaging:

Stage is somewhat wider than deep but does manage good height and a decent sense of proportion.    Seating the orchestra is straight forward as instrument separation is above average and layering is also quite good so while the stage is a little shallow, it does seat everything as it should.     Imaging is only average here which is a bit of a let down.  Movements are more generalized than I would like to see as positions are imprecise and often tracking movement is more of a it went left than it went from point a to point b in space.    I found no tendency to compress as tracks got busier either so that is another point in the Solis’ favor.

 

Thoughts / Conclusion:

First off, kudos to Moondrop for having figured out the EST.  That driver has been a hot item recently but a lot of models got it just plain wrong.  I can honestly say that the treble here is very polite and if anything maybe a little too much so which is nothing short of amazing considering the EST’s natural tendencies.    That alone is a big deal because it means it is possible.   Having said that, most don’t purchase an in-ear for its technical merits, so does it merit your money?     The Solis does a good job with a lot of things and I really appreciate the near neutral tuning with enough energy to keep it engaging.  Too often neutral means boring and that is a tough line to walk with few iems below the stratospheric price points doing it well.    I think the issue for many may be that the market is quite crowded and even in Moondrop’s line other models may steal sales from the Solis.  To my ear, the S8 was very similar to the Solis and other than a bit of top-end extension gives the user 95% of the Solis for about 50% of the money.   I think the Solis is well worth an audition as it is a detail oriented near neutral with good extension particularly at the top-end but whether buyers will decide to grab one may well depend on how much improvement they perceive compared to things like the Moondrop S8 and Dunu Sa6.