Future Sonics Ear Monitors with 13mm MG6pro Dynamic Drivers

Average User Rating:
  1. shotgunshane
    "Sadly dissappinting and tragically flawed"
    Pros - Friendly staff
    Cons - 3k-4k boost is harsh, echoey and fatiguing; bloated bass
    Future Sonics MG6Pro
    If you’ve read any of my previous reviews or impressions, you know I’ve been a fan of dynamic drivers for a long time.  In general, I find them to be more textured in the low end and overall portray a more natural or realistic sound for most instruments.  As of recently I’ve rediscovered a love for the separation, layering and intimacy many great balanced armature designs bring to the table.  Some have believed that hybrid designs could possibly bring out the best of both worlds.  I guess you could say that I’m a believer too, as I am quite fond of the UM Merlin and its musical and engaging presentation; but for anyone that’s a fan of dynamic drivers, that means you’ve ultimately had your eyes on the Future Sonics MG6Pro – with its 13mm driver and heritage from the Atrios line, known for its unmatched sub bass performance.
    I’ve been considering and ultimately planning to purchase the MG6Pro for many months.  It just so happens I stumbled into a UM group buy that eventually led to a UM Global Promo event, that ended up postponing my plans for the MG6Pro but back in mid February, I decided to take the plunge on what I hoped was the dynamic driver end game.
    I decided to have my impressions taken with the same audiologist that did them from my Merlin purchase, since those turned out so well on the first try.  Turnaround time from Future Sonics receiving them to shipping them back to me was a little over 3 weeks.  Turns out they had a very large order for the singing competition, American Idol, which was placed around the same time.
    The Carousel:
    Upon receiving them, the first thing I noticed was the classic fit issue.  They were too small in areas and easily lost seal.  I noticed that I was also experiencing a lot of harshness and an echo effect that made them very fatiguing to listen too.  I immediately contacted Future Sonics customer service, which were very friendly and professional.  They ask me to send them some pictures of CIEM’s in the ears to determine if a refit or complete rebuild would be necessary.  Unfortunately a complete rebuild ended up being necessary, so I had to return to my audiologist for additional impressions.
    Since this time, I have learned several things regarding impressions, molds, and the CIEM final product.  The first is that the customer plays a large part in the quality of the impressions.  For instance, did you clinch your jaws or where you relaxed?  Did you look down or look up too much?  Did you schedule them when you were sick or dealing with allergies?  Secondly it is also important that your audiologist follow the manufacturer’s directions in making the impressions.  Did they use a bite block? Do they have experience with musician’s monitor impressions?  They are made slightly differently from hearing aid impressions, as they require a tighter fit and closer tolerances.  And lastly the manufacturer can indeed make mistakes along the way, as confirmed from other members of this trade, from trimming the impressions, to the shaping and sanding stages and lastly when polishing the final product.
    After sending in new impressions, along with the CIEM’s themselves, Future Sonics also graciously allowed me to change the color from purple to smoke.  I’m guess I’m just not much of a flashy person when it comes to accessories.  I received the rebuilt set in early April.  Unfortunately I needed to send them back again, due to the nozzle portion of the right ear causing some discomfort and well as both faceplates sticking out from the ear too much.  I received a great fitting pair of MG6Pros in late April but unfortunately the issue of the harshness and echo effect, from the beginning, was still there.
    The harshness and echo effect I was hearing seemed to be coming from the 2k and 3.5k ~4k areas.  It was explained to me that Future Sonics has some peaks in the frequency response there to help balance the overall sound presentation out with the bass response.  My sensitivity to these peaks seems to be greater than most, as Future Sonics has never had anyone complain about a harshness.  It causes the tops of vocals and edges of guitars to become painful, fatiguing and ‘echoey’, which obscures details.  Also cymbals in busier drumming passages became blurred, creating a lack of treble detail and some ringing.  It’s as if someone turned the ‘presence’ knob to 11 on a guitar amp.
    Upon sending them in for the 3rd time, along with some music tracks so that the techs and owner could hear what I was hearing, it was decided to rebuild and replace the components (which they do on any rebuild), to rule out any other possible attributing factors.  I’m doubtful the Future Sonics staff was able to hear what I was hearing but they assured me the last set had passed their listening tests for the sound Future Sonics is known for.
    I received my MG6Pro for the 4th time in early May.  The harshness, echo effect and blurred treble detail remain.
    The MG6Pro contains a new, proprietary 13mm dynamic driver.  The shell is vented in the center of the faceplate.  It comes with 3 different sized vent inserts (S, M, L).
    • 18Hz - 20,000Hz TrueTimbre™ Response

    • 32ohm Impedance

    • Sensitivity 114dB @ 30Hz 
    Future Sonics also includes a future $199 upgrade path for when new versions of the driver are released.  Upgrades include the new driver, sockets, vent inserts, cable and are performed with your existing molds.
    In addition to the cable and vent inserts, Future Sonics includes an Otterbox 2000 that is custom engraved with the buyers name, as well as a pleather pouch for keeping your CIEM safe.
    Most of my listening is done on the move, whether commuting, walking or moving from one room in the house to another, so my testing is done on portable/transportable equipment.  I’ve used an iPhone 4, Nano 6g, Laptop, Headstage DAC cable, WhipMod 5g iPod and an Objective 2 amp.
    Future Sonics marketing states the MG6Pro sounds as:
    “The mg6pro™ are multi-driver & crossover free; delivering full range audio w/ natural hi-end sparkle, warm mids and a low-end frequency response no two, three, four or more way balanced armature earpiece can touch! mg6pro™ Ear Monitors® audio signature, reliability and workmanship allow performers to hear themselves with exceptional clarity; while our BIGGER SOUND at lower volume™ promise continues to deliver the best sonic performance possible.”
    Bass is first and foremost the allure and attraction for many to the MG6Pro.  In this respect the MG6Pro does not fail to deliver.  It has a great sense and feeling of power, unlike anything I’ve heard or felt in an IEM before.  It really can move a lot of air.  The following statement came from another head-fier in a discussion we had regarding dynamic drivers in general but I really think it applies to the MG6Pro:  Most IEM’s reproduce the sound of bass, rather than produce bass itself.  The MG6Pro produces BASS.
    That being said, I find the bass of the MG6Pro to be much too big for my tastes, even with the smallest vents.  The entire bass range is elevated and increases presence with the larger vents; this increased presence makes the bass bloom, lose tightness and mask texture.  This increased presence also affects the lower midrange, obscuring details here and robbing male vocals of clarity and a musical presence.  Compared to the Merlin, the overall bass quantity in both sub and mid bass is a good bit larger in the MG6Pro.  However the Merlin has much less mid bass presence and tighter sub bass that reveal more texture, as well as not affecting midrange clarity and detail.  Applying some EQ to remove the bass bloom around 250hz and lower, the MG6Pro bass displays better texture, improves tightness and allows lower midrange clarity and details to shine.  Overall quality of bass is greatly improved but overall quantity is still very plentiful.  Further EQ to remove bass throughout the entire lower region brings better overall balance across the frequency response. (Note: I use the medium sized vents when using EQ.  The reason for vent choice will be discussed later in the review.)
    The midrange of the MG6Pro, especially the upper midrange, is a bit of a Jekyll and Hyde presentation for me.  The lower to middle frequencies of the midrange (500 – 1.5k) come across as laid back and slightly recessed.  It definitely takes a back seat to the bass and upper midrange/lower treble (2k – 4k) areas.  Deeper male vocals fall behind lead guitars and drums, especially in busy passages of hard rock and metal, and even more so during bridges, choruses and leads.  However the upper midrange has some very forward peaks, which seem to cause unwanted resonance with my ears.  This upper mid peak is what causes the tops of vocals and distortion guitars to appear harsh to me.  Some singers in some songs are just too strident and it quickly becomes fatiguing and I find myself clicking to the next song.  For instance, in any classic Van Halen song, Michael Anthony’s backing vocals are very piercing and echoey. 
    These peaks in the upper midrange become harsher as the vents become smaller, so while I prefer the un-EQ’d bass of the smallest vent, I’ve resorted to the medium vents for the slightly less accentuated upper midrange peaks.  This effect on the upper midrange causes vocals to become less detailed and un-engaging.  Comparatively, the Merlin vocals are more transparent, detailed and engaging with a real sense of intimacy.  By EQ’ing these peaks down a few decibels, I’m able to remove the harshness I hear and eliminate the ‘echoey’ effect.
    Treble can be hit or miss for me depending on the type of song and the recorded quality.  When listening to a higher quality recordings for acoustic and singer/songwriter tracks, treble is laid back but cymbals, rides and high-hats are weighty and sound very realistic.  There isn’t any overly bright emphasis that some earphones put on top end; however it is somewhat pushed further back in the overall presentation.  On lesser quality recordings and very busy drumming passages in hard rock and metal, the upper mid/lower treble peak causes it to blur details and cymbals to run into each other producing a ringing effect.  However, when I EQ the upper mid/lower treble range down by several decibels to remove the harshness and echo effect, cymbals/rides/hi-hats are rendered superbly, with high levels of detail and fantastic timbre.  Also EQ’d up in the upper treble frequencies; it becomes possibly one of the most realistic treble I’ve heard.  Again, treble weight comes across to me as nearly perfect.
    Regardless of vent insert size, I find the overall width of the soundstage to be slightly below average, which was surprising as I usually associate venting as having more of an impact on soundstage width.  Instruments seem very close together from right to left, which also negatively affect imaging.  However the soundstage depth is among the deepest I’ve ever heard. (note: The upper mid/lower treble peaks exacerbate the soundstage issues.  It does open up with EQ.) In contrast the Merlin soundstage is both wider, by a considerable margin and also taller. The MG6Pro serves up a very blended, organic and coherent presentation.  It’s quite the opposite of your typical balanced armature presentation that tends to separate every instrument in its own space within the headstage.  Again, in my case with proper EQ, instrument realism is very convincing; at times I feel like I’m in the same room with the piano, acoustic guitar or drum kit.  While the MG6Pro has a very natural tone, I do find transparency takes a hit at the expense of the massively thicker note and accentuated bass response.
    It bears repeating, that to my knowledge, I am the only one to experience the harshness, echoey and blurring effects I’ve described in my review.  It’s also not typical to discuss how an earphone sounds after EQ in a review but due to the apparent resonance issues I have with the Future Sonics tuning, I felt it important to bring this into the discussion.

    Edit: since the original writing of this review, I have received PM's from 4 to 5 other mg6pro owners confirming that they too hear issues similar to what I've described, albeit to differing levels.
    In Sinocelt’s reviews, I found the tool he often referenced, http://www.phys.unsw.edu.au/jw/hearing.html, extremely useful in determining where the frequency peaks and valleys were located.  I also used the iPhone app, FreqGen, to further pinpoint these peaks and valleys.  After spending a few hours precisely pinpointing my issues with these tools, I was able to create this EQ curve using the iPhone app Equalizer:
    This interactive chart, http://www.independentrecording.net/irn/resources/freqchart/main_display.htm, shows where various instruments fall within the frequency range and how the various areas can affect how you hear them; thus explaining what the 2k and ~4k peaks were causing me to hear.
    I simply cannot listen to these without EQ. The stock sound is peaky, harsh and echoey with extremely bloated amounts of bass. 
    Raketen likes this.
  2. bmiamihk
    "Just received my Future Sonics MG6pro custom earphones"
    Pros - Bass ( you can hear and feel), sound stage, clearity, fit
    Cons - inserting and removing
    I just received my FS custom earphones. I have their universals earphones (Atrios) so I was expecting similar but more of all the good stuff (Bass). Well I did get what I expected. More wider hard hitting bass that I can hear and physically feel. I can feel my ears being pounded with clear sub bass. when i remove them it feels as if my ears have to recover from a fist of bass smaking them over and over. The meds and highs are clearer and wider then their universals. These earphones have a warm feel and I can easily make them brighter with my EQ but I like the warm feel to them. I do have some expensive BA earphones which I do like but to get the bass I have to raise the volume higher than normal and when I remove them from use I tend to have a high ringing sound a fatigue that I did not get from the Atrios. The custom now does not cause fatigue but I feel my ears took some hard sub bass massaging which takes some time to go away. it is not a complain I like it, I want the bass. Now inserting and removing is a lot of work! with all my earphones (universals) I loved the foamy tips so easy to put them in and get a seal and head out doors. With the custom FS I have to work to get them in and fit them correctly. Boy, It seals very well and can be scarry cause I cannot hear anything besides the music so when someone approaches me I keep getting surprised. Removing them is also work I have to twist them and pull them gently using muscle to get them out. I guess I have to get used to them seems these go a lot deeper then the JH 13 pros. I only burned them in for 5 hrs and there has been a slight change in the sound. I liked how they first sounded and I like the change as well. lets see (hear) what happens after more usage.
  3. fusionramjet
    "the mg6pro is awesome"
    Pros - smooth, natural, cohesive, incredible bass
    Cons - possibly could be more detailed [see below]
    I've had the mg6pro for 7 days now and I've been in sonic bliss [​IMG].
    Kunlun's review, which led me to my decision to get them, is excellent (Very detailed and thoughtful).
    re: the possible con (for me): i might possibly like a bit more balanced-armature type detail but not the artificial-sounding detail i hear with my Westone 4.
    Of note, their client services is very responsive, kind, and helpful!

  4. SammyDplus
    "FutureSonics MG6 Pro IEM"
    Pros - Real Sound, Comfort fit, Instant Results
    Cons - None
    Hi everyone, here's my first (brief) review of the MG6 Pro In-ears by Future Sonics..
    First, i'd like to note that Mr. Marty Garcia (CEO FutureSonics) is a complete gentleman, he took time to answer ALL my questions on phone and emails too! That's rare and heart warming.. - a far cry from Sensaphonics where i encountered a completely rude rep, and Ultimate ears that won't answer or reply any calls!
    It took less than two weeks to get my custom IEM, everyone i called and spoke with at FutureSonics were polite and helpful; i was surprised at how quick i got my order.
    Ok, now to the technical stuff and results; My Custom In-Ears were a perfect fit, i also had custom earplugs made and those fit perfectly too.
    The first test on the Custom MG6 Pro was with my iPhone 4,
    'listened to "4 Seasons of Loneliness" from Boyz II Men; I noticed an INSTANT difference and improvement from EVERYTHING i had ever had or used. -Trust me, as a drummer; i've tried a lot - from the Heavy heat-and sweat-inducing VicFirth headphones, to Bose Noise cancelling QC15 (quite good.. and light too!), and all sorts of earbuds.. but nothing comes close to the MG6pro! The bass was deep and CLEAR, everything from vocals to hi-hat was solid and neat. No "coloring".
    Next was the REAL test; i got into my drum room/studio and decided to test them for a minute.. well, i didn't stop until 12minutes later! The isolation was just perfect for me, even in an enclosed space.. Then i tried it with my play alongs and backing tracks, EVERYTHING - including my drums (Mic'd) came out crystal clear and neat!
    In my own opinion, these are the best you could ever get.. and talking about In-Ears; I'm glad i chose Future Sonics, the drivers are actually REAL SPEAKERS, you feel the air, and thus the real vibrations you'd get from low frequencies. -as opposed to other IEMs that uses Armatures; armatures are supposed to be used for hearing aids, thats what they're REALLY for, and that's why they have "twelve-driver per ear" IEMs trying to create the "ideal" sound.. oh, well, i guess the choice is for everyone to make.. This is just my own take on Armatures Vs. Dynamic -real- Speakers.
    Here are my pictures.. for now








    * I'll be posting more pictures shortly..

  5. Kunlun
    "An Excellent Dynamic Driver Custom In-Ear Monitor with a Natural, Balanced, Smooth Sound."
    Pros - Incredibly natural sounding with perfect timbre. Excellent extention, soundstage and overall balance, Real Bass Energy + adjustable quantity, Durable
    Cons - Natural, balanced sound may not be for those who prefer a colored or boosted sound, isolation can be good, but with vents open it loses a few decibles

    Synopsis: The Future Sonics MG6Pro Ear Monitor is an excellent sounding custom earphone tuned for a supremely natural sound. The overall sound is very smooth, extended in bass and treble, and very well balanced by the clear midrange. The excellent reproduction of vocal and instrumental timbre, combined with superior soundstage and sense of stereo imagining are also standouts. Using a single dynamic driver which can cover the entire frequency spectrum without the need for crossovers gives the MG6PRO Ear Monitor a coherency which adds to the naturalness of its presentation. The bass deserves special mention for its control and its effortless extension down to the sub-bass frequencies. Additionally, the 13mm dynamic driver can move the air against our ears in a way balanced armatures cannot—this leads to better bass energy as we “feel” bass as much as we hear it. The amount of bass can also be adjusted to anyone’s taste by a changeable system of vents which allow the driver more or less airflow.

    Introduction: I’ve always really been drawn to earphones that feature a dynamic driver (also known as a moving-coil). These are basically like the speakers in one’s home stereo, only smaller. When I looked around for a custom-fit earphone, however, I noticed that almost every company uses balanced armatures, a technology used in hearing aids. One company, however, has been offering a dynamic driver custom in-ear monitors on stage for years. In fact, Future Sonics has been doing it so long they trademarked the term “Ear Monitor” and the owner, Marty Garcia, was the first to put custom in-ear monitors on stage, back in 1985. The fact that Future Sonics used a dynamic driver and the length of experience made me curious. Even more curious was the fact that while they are well-known in professional music circles for supplying Ear Monitors over the years to bands like The Grateful Dead, U2, Reba McEntire, Justin Timberlake, etc., they aren’t so well known in audiophile circles.
    History and Background: When I had a chance to speak to Marty Garcia, the owner, and David Gray, director of operations, it was clear that the use of a dynamic driver in their custom earphone was the result of careful thought. While every other custom earphone manufacturer that I am aware of buys their transducers from outside manufacturers, Future Sonics engineers their own. The new for 2010 MG6Pro is a proprietary driver designed and made by Future Sonics. The history as I understand it from talking to Mr. Garcia is that he experimented with using balanced armature transducers multi-armature designs with crossovers. He consulted for Shure on their early designs and politely parted ways when he decided that a single dynamic driver was the way to go. He feels that a single dynamic driver has a number of advantages: It can cover the frequency spectrum by itself, it gives a coherent sound free from any artifacts from a multi-transducer approach and, very importantly, it moves the air that we can feel as well as hear for a more real sounding bass with living energy. Interestingly, when I spoke to K.W.Karth, who designed Monster Cable’s Turbine earphone, he gave many of the same reasons that Monster Cable went with dynamic drivers in their universal fit line of in-ear monitors.  
    Disclaimer: I think it’s important to be open and up-front about the way one has received the product reviewed, so everyone can be clear about any underlying motives which might bias the review. As for me, I paid for mine, however I did receive a small discount.  I had just missed out on a one-time sale on Ear Monitors in celebration of Future Sonics’ 25[sup]th[/sup] anniversary. They were kind enough to offer me a discount that ended up coming to $50 (a slightly larger discount minus the extra I paid going to a Future Sonics’ recommended audiologist on Mr. Garcia’s request). I’m happy for it, of course, but the opinions below will be my best attempts to honestly convey how these earphones sound.
    Customer Service: Custom in-ear monitors take a lot of care. Throughout the process, I’ve really been struck by how important the custom service of the company you work with can be. Future Sonics deserves a lot of credit for the very high level of customer service they’ve provided. The fact that the owner of the company made time to really discuss his product and the philosophy behind it on several occasions speaks to how Future Sonics treats its customers. All my concerns (and I am a high-maintenance customer, so this is a lot of random concerns) have been graciously answered in over 60 emails…and counting! They have really gone the extra mile and treated me like the rock star most of their other customers are.
    One of the first steps in getting a custom in-ear monitor is a trip to an experienced audiologist to make ear impressions which will be used to make an earphone which fits your unique ears perfectly. I went to Andrew Resnick, a Manhattan audiologist and Future Sonics dealer. He was professional and had a lot of experience in making ear impressions for musicians’ Ear Monitors. I won’t say that this means I haven’t needed adjustments to make the fit of my MG6PRO Ear Monitors perfect, but I think it has helped to start with a good set of impressions.
    The MG6Pro: This is a custom in-ear monitor with a 13mm dynamic driver at its heart. My understanding is that Future Sonics released the MG6 early in 2010 to audio professionals and field tested it. They took that feedback and improved the driver further, with the MG6Pro coming out a few months after.
    One key point about these customs is that their dynamic drivers are very durable and much more easy to service than armature-based customs, which tend to be more delicate. You can also upgrade your MG6Pro Ear Monitors whenever the next generation comes out for a fraction of the price of a new monitor! Think about that, it’s a great feature.
    Another interesting thing about these is that while the outer shell is acrylic, but it’s not an all-acrylic design! A dynamic driver requires special positioning and so they use a second, proprietary, material inside to properly seat the driver. This second material is full of tiny bubbles and that gives a clear acrylic MG6Pro Ear Monitor an interesting look (of course, it can also come in many different colors, even in a chrome finish).
    Another interesting feature is the system of Low-Frequency Vents (LFVs). In order to move the air for living bass energy, a dynamic driver needs to breathe. The 4 LFVs are little tiny interchangeable plugs with a hole (the vent) in them. They vary from a smaller hole to a medium hole to a larger hole, or no hole at all. One can easily be removed and another size vent used in its place. Each larger size brings up the sub-bass presence and energy up a bit. It also effects isolation, which I’ll discuss next.
    Isolation: This, like the bass, is dependent on the Low-Frequency Vents. Using the LFV which closes off the vent, one achieves what I imagine is the exactly the same isolation as any other acrylic custom monitor. With LFVs which allow air to pass, there is a loss of a few decibels of isolation, but the isolation is still respectable. Going out into a wind-tunnel of a chilly winter day with the MG6Pro and the medium size opening LVFs, there was good isolation, but there was a small amount of wind noise--it was very windy outside! You gain something in sound for any loss, though, so it all depends on your situation. I like to use the medium sized vents and have no problem using it on the subway, but then, my isolation needs aren’t so great. If I needed more isolation, I might use the LFV which seals the vent entirely, for maximum outside noise reduction.
    The Sound: The head audio engineer for the Country Music Awards told me (yes, I emailed him and asked what he thought) that Future Sonics Ear Monitors offered “true reference quality sound”, in his opinion. I’m not a professional audio engineer, but I can definitely hear where he’s coming from.
    The overall sound signature is natural, balanced and engaging.
    What natural means to me is that the MG6Pro doesn’t sound colored or boosted to me anywhere in its frequency range. It also refers to the superior timbre—that hard to define but easy to recognize ability to convey the true-to-life sound of all the richness and subtle resonance of an instrument such as the human voice or a violin. I think that these qualities are part of what the senior audio engineer I politely pestered was talking about.   
    Balanced means to me that I don’t hear a certain frequency range coming ahead of any other, generally speaking. With the LFVs, this can change a little according to one’s taste, as I’ll mention below.  Other earphones may be tuned with a very forward midrange, or a boosted extra-bright treble or a mid-bass hump to give beats extra bounce—the MG6Pro has none of these, to my ears. I think people who want a colored (“fun”) sound won’t necessarily find that the MG6Pro is for them. It’s just a matter of knowing what kind of sound you are looking for and matching your preference to the earphone you buy.
    And that brings me to the last adjective, engaging. These are professional reference and stage monitors, but they can really rock and I often find myself listening for longer and enjoying my music more.
    Treble: This is a stage monitor in its tuning, so the treble is non-sibilant and non-fatiguing. The treble is well-extended, and nicely shines and sparkles. It’s accurate and both violins and female vocalists, as well as cymbals, chimes, etc. all come alive with a good recording and the MG6Pro. However, it’s not the bright treble of a lot of earphones, so some people might say it’s dark at first (although I’d say it’s more neutral, just dark in relation to someone used to something bright sounding). I spoke to Marty Garcia about how some people found his Atrios (universal-fit earphone) line a bit dark. From his own work as professional audio engineer and working with professional music clientele, he felt that it was better to give a natural treble than one he thought was boosted. I can say the MG6Pro has a great natural treble. Lovers of treble on the bright side may wish to look elsewhere.   
    Mid-range: The mids of the MG6Pro really let the music sing without getting in the way. Whenever I try to describe them, I try listening to some music…and end up listening and listening… So, I think I can say first that they are not recessed, nor are they overly forward. It’s not a thin-sounding earphone by any stretch, but notes aren’t overly thick nor does the decay overstay its welcome. They are quite well-detailed, but not artificially analytical. I think you can see why I keep coming back to natural and balanced as descriptions.
    Bass: I was surprised by just how well mannered and controlled the bass on these was while still giving that moving-air living bass energy that I wanted. It’s very well detailed and layered. The bass doesn’t have a mid-bass hump and doesn’t intrude on the midrange. It does, however, extend down all the way past human perception. Marty Garcia mentioned that Ear Monitors are intentionally engineered to give bass down to 10hz (where we can’t really hear it) because he feels that the feeling of the air against our ears at that vibration still adds something meaningful. I have to say that I have experienced what he means, it’s really something interesting and there is a life and a dimension of space added to the bass somewhere deep in that sub-bass range.  Further, I can also say that there really is something to this moving air quality that is part of our perception of bass. This is one of the key things that sets the MG6Pro apart from armature-based customs as they don’t move the air. When I use my fingers to plug the MG6Pro’s vents while listening, the effect is immediate and tangible—I feel a slight but noticeable pressure in my ears from the driver moving air! It’s also not recommended, but I did it for science.
    On to the Low Frequency Vents: With the LFV which seals the vent entirely, the air cannot fully move and the sub-bass takes a step back. It’s very well controlled and still present, but sounds to my ears politely as though it allows the mids, and treble to take the lead forward. This is probably many audiophiles’ idea of balance and they will love this sound. The isolation is also the greatest with this LFV.
    The small opening LFV lets the driver breath and the sub-bass takes on that added dimension of life and comes up a little, with a small loss of some isolation. The bass quantity is equal with the midrange to my ears and things will be just right for many listeners.
    The medium opening, well, this is my favorite at the moment and I would say it’s pretty great as the sub-bass comes up by a decibel or so, yet still balanced.
    Even at the largest opening LFV, the bass is well controlled, but it’s presence and space have increased. I could see this LFV being very nice for stage use. Lovers of bass will like this setting as well, although I would not say it’s overmuch to my ears.
    Music genres: I tend to listen to classical and Indian classical music, both types of music that require excellent timbre, good levels of detail while remaining natural-sounding and excellent extension in the bass and treble. Anyone who thinks that classical music lacks bass has never heard a timpani or double bass in a symphony! The MG6Pro handles these music types very well, sounding coherent yet with the spaciousness to avoid any congestion. Every part of the orchestra sounds clear, even as they are all playing together. Stereo imaging, the out-of-the-head sense that each musician is playing in a different space, is excellent. I was happy to note that the non-sibilant treble could also extend high and sparkle with piccolo trills, chimes and sopranos hitting the highest of notes. String quartets sound lovely, solo piano, too. Jazz is another genre the MG6Pro does very well with, unsurprisingly.
    I also listened to some fast trance and some Norwegian death metal to see if the MG6pro could keep up. While they aren’t my cup of tea music genres, the MG6Pro is clearly completely at home with trance, its spaciousness is unreal for this music and it has the speed for the death metal, every hoarse shout and growl was…you know, I really need to talk to the guy who recommended that…
    For a bit of rock I listened to one of my favorite drummers, Thomas Pridgen, and a few tracks from the band he used to be with, The Mars Volta. The MG6Pro captures his drumming very nicely and I’m happy to report that his cymbals sound real, which is something that not every earphone reproduces well.
    There really isn’t a type of music I could see causing a problem for these earphones. That’s what you expect at this level. It’s nice to confirm, though.
    In Conclusion: I think these custom in-ear monitors have a lot to recommend them for professional or audiophile use. They certainly deserve more attention from audiophiles as they have a high quality sound with excellent customer service. The way they can be upgraded to the next generation driver for a fraction of the cost of a new custom, their durability and ease of repair and the way the bass quantity can be adjusted make them a very strong choice. Certainly those who come from dynamic driver earphones or headphones should think about the MG6Pro Ear Monitor, as well as those wanting a balanced, natural sound at every part of the frequency range. Those who like a very bright or a colored sound generally might wish to look at other options.
    P.S. See comparisons with other earphones including the JH16 in my review annex!