[Frankie D]

While I appreciate your comments, it is as if you and I are listening to two different IEM's, regarding your bass comments. While the "blue tips" are supposed to be the default tips, I have found that the Spinfit CP360( generally don't like Spinfit) and as other have said the Sedna Earfit Light short will also give you a great sound quality. I also feel the other Azla Sedna tips(black) provide wonderful bass as well. The Spinfit CP100 are not to the same level as the CP360.

I am not a fan of quick listen impressions, but without any seasoning the Luna has great bass. I think that folks should try what others have stated, and try "tip rolling" before posting initial impressions. I have not heard the Anole VX so I cannot compare.

Using the next song on Graceland, I Know What I Know, the bass has clarity and authority.

What I want to do is provide the community with my impressions over time. Also, please understand the VX is one of the best IEM’s out there in my opinion. I chose them because I felt they were better than everything else at the time. They are also in another price bracket. That being said, the Luna impressed me at the show which is why I got them. I will be honest and I will try different tips in the future. And I am sure the Luna will get better. Tks.

 

[ranfan]

Love my new Fiio M15. It is a substantial upgrade from my previous Shanling M5s and Ibasso DX160. If you guys see reviews online it is a bit mixed for reviews but so far my M15 has easily been my best source. What they don't really go over is just how good the M15 is with IEMS.

The Luna is resolving of the source it is being used so be aware of that. If your using a neutral sounding source your Luna will sound neutral. If your using something like a M15 where sonically has layers and layers of dimensional sound. Your gonna get that in spades out of the Luna.

I laugh when I see guys saying Luna is bass light. Your not hearing them right. Or your used to having earphones with much bass. My Luna on my M15 rumbles with the best of em.

Some guys online will tell you the M15 is not worth it. Some will say the Luna looks like it has limp noodle bass..
I will say the exact opposite. the M15 and the Luna is made for each other no other way to put it. I am very picky about my bass folks. I would gladly tell you if these are weak in the bass arena. What I hear is plentiful accurate bass that has excellent resolution, speed, detail, impact and extreme texture. Luna may not be a bass first iem and you gotta remember that but what it does have is a very even fine balancing of the highs mids and bass. No part sticks out above the other. If your looking for a bass first iem. There are much cheaper alternatives that will thump your brains if that is what you want. But if your a balanced head. The LUNA is worth every penny.

I would take some of the online reviews with much grain. If you have a good source you already own. The Luna will show you just how good your source is.

I haven't heard the M15, but it sounds like a good player. It's nice for someone to discover a harmonious synergy between the player, IEM, and the subjective preference. It's like completing all the boxes in sudoku (lol). The AKM is well-known for its technicals, layering, and resolution. From my experience with AK players, they tend to sound so. It may boost the strength of the LUNA also then.
About the bass, I know very well of an IEM which has a light bass. It's in my profile picture. The one BA design Prelude. That said, it has the most beautiful midrange I've heard yet. There is something alluring to me in a one driver IEM. Like bauhaus simplicity, of finding the optimal point between form and function. How NASA managed to land Apollo to the moon, despite all odds. The bass on the LUNA is well-tempered, and evenly distributed. Its reach is far, and it rumbles quite well. It is not bass light relatively speaking. Only that it values being true, more than being loud. The LUNA has a balanced sound, and extends nicely on both ends. Its strength I think lies in its resolution, and how it can portray music as is without much coloration. Of course as always YMMV.

 

[Frankie D]

Thank you very much for sharing your impressions. The bass has been my concern after seeing BGGAR’s comments and has stopped me from pulling the trigger. Will be interested to see how they go for you after a bit more burn-in. Please keep us posted!

I will. Tks.

 

[subguy812]

I haven't heard the M15, but it sounds like a good player. It's nice for someone to discover a harmonious synergy between the player, IEM, and the subjective preference. It's like completing all the boxes in sudoku (lol). The AKM is well-known for its technicals, layering, and resolution. From my experience with AK players, they tend to sound so. It may boost the strength of the LUNA also then.
About the bass, I know very well of an IEM which has a light bass. It's in my profile picture. The one BA design Prelude. That said, it has the most beautiful midrange I've heard yet. The LUNA isn't like that. There is something alluring to me in a one driver IEM. Like bauhaus simplicity, of finding the optimal point between form and function. How NASA managed to land Apollo to the moon, despite all odds. The bass on the LUNA is well-tempered, and evenly distributed. Its reach is far, and it rumbles quite well. It is not bass light relatively speaking. Only that it values being true, more than being loud. The LUNA has a balanced sound, and extends nicely on both ends. Its strength I think lies in its resolution, and how it can portray music as is without much coloration. Of course as always YMMV.

I have been a big fan of A&K players, as a matter of fact, my main player is the Kann Cube, I love it. I have others as can be seen from my signature but is has a fantastic synergy with Luna. I am surprised at the synergy with the iBasso DC01 and the S20 Ultra as well. I haven't used a Fiio player since their days as a budget company and their UI drove me crazy, but I am sure it has improved.

Edit: I guess I removed DAPs from my signature...sorry

 

[ranfan]

I have been a big fan of A&K players, as a matter of fact, my main player is the Kann Cube, I love it. I have others as can be seen from my signature but is has a fantastic synergy with Luna. I am surprised at the synergy with the iBasso DC01 and the S20 Ultra as well. I haven't used a Fiio player since their days as a budget company and their UI drove me crazy, but I am sure it has improved.

Big Kann The many patches FiiO releases was the thing for me to opt for Cayin. But for pure sound, I'm not sure which is better.

 

[jmills8]

Big Kann The many patches FiiO releases was the thing for me to opt for Cayin. But for pure sound, I'm not sure which is better.

Once you know , you know and the chase , wishes , hopes ends , cause you know.

 

[hop ham]

Bass seems to be discussed a lot. I think there is a forceful weight behind the bass…its very capable and enjoyable. Not overbearing but has good impact. It's a deep (rumbly when it needs to), fast anchor. It doesn't get in the way but is always there to the degree it needs to be. The Legend X bass is crazy and overdone - could be addicting and fun or could annoyingly get in the way. Luna's bass doesn't shout for attention like Legend but it's not laid back to me either. I don’t fault any aspect of Luna's bass. I respect it and appreciate the balance and blend it has with the rest of the spectrum.

I always try my IEMs with Dave/Mscaler to see how they scale and impart their own character, plus it's fun to hook up IEMs to an overkill desktop rig. Luna changes with the source, easily detectable. M15 adds some thickness and warmth but is highly detailed and engaging AF. Dave is more lifelike, more airy and spacious. It reminds me of Verite straight from Dave. These are the only sources so far that I've used a good amount with the Luna.

Luna scales as well as any IEM I have including KSE1500. It's not quite as liquid flowing sounding as KSE but nothing I've tried is. KSE isn't perfect and overall I prefer Luna mostly because of the bass and balance. For me, KSE is engaging through resolution and liquidity whereas Luna has both those checked off to almost the same degree and can be engaging in more/different ways.

There were times I sensed some dryness but that has mostly gone away, for example with almost no burn in connected to DX200. I wouldn't say they are clinical or cold sounding but more on the reference side so think about what source you're planning to use it with. If you're using an very analytical DAP, it could potentially sound thinner and dryer than you'd like. I enjoy mid-centric IEMs that do well with vocals and I don't mind some extra sweetness to color the sound and add emotion. I don't hear any coloration on the mids but I connect with the feeling behind voices. I really like vocals with M15. I don't feel like Luna adds emotion to voices but with instruments it is so nuanced with good timbre that I feel them more. I enjoy vocal harmonies because of the imaging and how they are layered and the lightness/airiness of delicate female voices - try Jolene by The Staves on the Pine Hollow Live album.

I like the design. Small and light housings, easy for me to insert for the right type of seal. With so many of my IEMs with huge shells, I really like the small light factor similar to KSE. To make it super light and almost disappear I might go with a Linum cable. I easily forget they are in my ears after hours, no discomfort. I'm currently using the blue tips but experimenting. Cable is fine. I like the modular plugs. Under the Y split it has a tiny bit of memory - would prefer it more pliable but really does not bother me. Not my perfect chin slider but at least its there, and why am I talking about chin sliders?

Never was sibilant. For reference, Utopia with stock pads is always straddling the edge of sibilant to me but mostly stays right below that point. Imaging is really impressive. Not a very large soundstage but with such good imaging, notes hold their own space within the boundaries and makes it seem large by creating this affect. It reminds me very much of Utopia in this way. You heard people say the sounds come at me from the blackness/nowhere and are pinpoint.

The word others have used is Coherent. I agree, very well integrated sound. If you pay attention to the details of a specific note/instrument/voice, you can still be grooving with the music as a whole.

These might not be my overall favorite IEMs but they provide a different presentation that I appreciate and has a place within my collection. Not my favorite (but still really good) with pop/rock/r&b/rap but I have other IEMs that excel at those. I think generally Luna does a remarkably good job with any genre. Acoustic, instrumental, ambient all sound especially good with Luna.

 

[subguy812]

Bass seems to be discussed a lot. I think there is a forceful weight behind the bass…its very capable and enjoyable. Not overbearing but has good impact. It's a deep (rumbly when it needs to), fast anchor. It doesn't get in the way but is always there to the degree it needs to be. The Legend X bass is crazy and overdone - could be addicting and fun or could annoyingly get in the way. Luna's bass doesn't shout for attention like Legend but it's not laid back to me either. I don’t fault any aspect of Luna's bass. I respect it and appreciate the balance and blend it has with the rest of the spectrum.

I always try my IEMs with Dave/Mscaler to see how they scale and impart their own character, plus it's fun to hook up IEMs to an overkill desktop rig. Luna changes with the source, easily detectable. M15 adds some thickness and warmth but is highly detailed and engaging AF. Dave is more lifelike, more airy and spacious. It reminds me of Verite straight from Dave. These are the only sources so far that I've used a good amount with the Luna.

Luna scales as well as any IEM I have including KSE1500. It's not quite as liquid flowing sounding as KSE but nothing I've tried is. KSE isn't perfect and overall I prefer Luna mostly because of the bass and balance. For me, KSE is engaging through resolution and liquidity whereas Luna has both those checked off to almost the same degree and can be engaging in more/different ways.

There were times I sensed some dryness but that has mostly gone away, for example with almost no burn in connected to DX200. I wouldn't say they are clinical or cold sounding but more on the reference side so think about what source you're planning to use it with. If you're using an very analytical DAP, it could potentially sound thinner and dryer than you'd like. I enjoy mid-centric IEMs that do well with vocals and I don't mind some extra sweetness to color the sound and add emotion. I don't hear any coloration on the mids but I connect with the feeling behind voices. I really like vocals with M15. I don't feel like Luna adds emotion to voices but with instruments it is so nuanced with good timbre that I feel them more. I enjoy vocal harmonies because of the imaging and how they are layered and the lightness/airiness of delicate female voices - try Jolene by The Staves on the Pine Hollow Live album.

I like the design. Small and light housings, easy for me to insert for the right type of seal. With so many of my IEMs with huge shells, I really like the small light factor similar to KSE. To make it super light and almost disappear I might go with a Linum cable. I easily forget they are in my ears after hours, no discomfort. I'm currently using the blue tips but experimenting. Cable is fine. I like the modular plugs. Under the Y split it has a tiny bit of memory - would prefer it more pliable but really does not bother me. Not my perfect chin slider but at least its there, and why am I talking about chin sliders?

Never was sibilant. For reference, Utopia with stock pads is always straddling the edge of sibilant to me but mostly stays right below that point. Imaging is really impressive. Not a very large soundstage but with such good imaging, notes hold their own space within the boundaries and makes it seem large by creating this affect. It reminds me very much of Utopia in this way. You heard people say the sounds come at me from the blackness/nowhere and are pinpoint.

The word others have used is Coherent. I agree, very well integrated sound. If you pay attention to the details of a specific note/instrument/voice, you can still be grooving with the music as a whole.

These might not be my overall favorite IEMs but they provide a different presentation that I appreciate and has a place within my collection. Not my favorite (but still really good) with pop/rock/r&b/rap but I have other IEMs that excel at those. I think generally Luna does a remarkably good job with any genre. Acoustic, instrumental, ambient all sound especially good with Luna.

These comments are made only after using bluetips? You haven't tried any others? How long have you had the Luna? I do agree with many of your observations.

 

[hkpants]

To add to the bass conversation, I don't find that the Luna lacks bass. I've only given it about 2 hours of critical listening so far, but I think the bass has a pretty good presence, wouldn't call it lacking. I've been switching between the stock blue tips and JVC Spiral dots, no issues with the bass on either.

 

[hop ham]

These comments are made only after using bluetips? You haven't tried any others? How long have you had the Luna? I do agree with many of your observations.

I tried Spinfits and Spiral Dots so far. Ordered the SednaEarfit Light Short as recommended by ranfan and others. I got the Luna a week ago - burning in constantly and have been listening to them a lot because we're stuck inside. I really like the signature.

 

[darveniza]

While in lockdown having some fun

 

[darveniza]

Bass seems to be discussed a lot. I think there is a forceful weight behind the bass…its very capable and enjoyable. Not overbearing but has good impact. It's a deep (rumbly when it needs to), fast anchor. It doesn't get in the way but is always there to the degree it needs to be. The Legend X bass is crazy and overdone - could be addicting and fun or could annoyingly get in the way. Luna's bass doesn't shout for attention like Legend but it's not laid back to me either. I don’t fault any aspect of Luna's bass. I respect it and appreciate the balance and blend it has with the rest of the spectrum.

I always try my IEMs with Dave/Mscaler to see how they scale and impart their own character, plus it's fun to hook up IEMs to an overkill desktop rig. Luna changes with the source, easily detectable. M15 adds some thickness and warmth but is highly detailed and engaging AF. Dave is more lifelike, more airy and spacious. It reminds me of Verite straight from Dave. These are the only sources so far that I've used a good amount with the Luna.

Luna scales as well as any IEM I have including KSE1500. It's not quite as liquid flowing sounding as KSE but nothing I've tried is. KSE isn't perfect and overall I prefer Luna mostly because of the bass and balance. For me, KSE is engaging through resolution and liquidity whereas Luna has both those checked off to almost the same degree and can be engaging in more/different ways.

There were times I sensed some dryness but that has mostly gone away, for example with almost no burn in connected to DX200. I wouldn't say they are clinical or cold sounding but more on the reference side so think about what source you're planning to use it with. If you're using an very analytical DAP, it could potentially sound thinner and dryer than you'd like. I enjoy mid-centric IEMs that do well with vocals and I don't mind some extra sweetness to color the sound and add emotion. I don't hear any coloration on the mids but I connect with the feeling behind voices. I really like vocals with M15. I don't feel like Luna adds emotion to voices but with instruments it is so nuanced with good timbre that I feel them more. I enjoy vocal harmonies because of the imaging and how they are layered and the lightness/airiness of delicate female voices - try Jolene by The Staves on the Pine Hollow Live album.

I like the design. Small and light housings, easy for me to insert for the right type of seal. With so many of my IEMs with huge shells, I really like the small light factor similar to KSE. To make it super light and almost disappear I might go with a Linum cable. I easily forget they are in my ears after hours, no discomfort. I'm currently using the blue tips but experimenting. Cable is fine. I like the modular plugs. Under the Y split it has a tiny bit of memory - would prefer it more pliable but really does not bother me. Not my perfect chin slider but at least its there, and why am I talking about chin sliders?

Never was sibilant. For reference, Utopia with stock pads is always straddling the edge of sibilant to me but mostly stays right below that point. Imaging is really impressive. Not a very large soundstage but with such good imaging, notes hold their own space within the boundaries and makes it seem large by creating this affect. It reminds me very much of Utopia in this way. You heard people say the sounds come at me from the blackness/nowhere and are pinpoint.

The word others have used is Coherent. I agree, very well integrated sound. If you pay attention to the details of a specific note/instrument/voice, you can still be grooving with the music as a whole.

These might not be my overall favorite IEMs but they provide a different presentation that I appreciate and has a place within my collection. Not my favorite (but still really good) with pop/rock/r&b/rap but I have other IEMs that excel at those. I think generally Luna does a remarkably good job with any genre. Acoustic, instrumental, ambient all sound especially good with Luna.

Your comment summarizes very well the bass . It's there, it's elegant and not just brute force

 

[Frankie D]

Entry 2 – 55 Hours of burn-in

Ladies and gentlemen, the bass has arrived! I would say not really because of the additional burn-in, but because of the changing of ear tips. And if I may be allowed to say it, the Luna is a pain in the ass when it comes to tips! The blue tips are the most comfortable to me, but also a bit bass light. When I move up to the large size (I am usually a medium) I can hear more bass. But still bass light in comparison to my final choice. Symbio tips work well, but I was not as comfortable in them as I like. I felt the spin fits were all bass light in my ears. The JVC Spiral Dots were not a match for me either. What worked the best for me? Final E tips in size L. Comply tips also worked well, but the Final are easier to put in and remove. There are some other recommendations as you all have read (The Azla SednaEarfit Light Short from SubGuy812 and Ranfan). I may try them in the future as well hoping for something more comfortable to me with the same sound (assuming I can find them).

The Luna now sounds really good, and I have provided a few comparisons below as examples.

Regina Spektor: Fidelity

Vs Fourte: The Fourte still hits a bit harder in the bass. But there is good bass in the Luna.
Both provide good air around her voice, maybe the Luna has a slight edge here. The Luna also has more detail than the Fourte. For example, when she sings the word “Heart” you hear the inflection of the “t” better. Both renditions are compelling.

Vs Anole VX Custom: The Luna delivers a lighter presentation. The bass hits harder, tighter, and with more detail on the VX. The VX has the edge in the midrange and treble as well. The VX provides a fuller presentation. You will hear the same detail, and a little different pitch in Regina’s voice (very slight) that is more accurate. There are times she changes the sound or inflection of her voice and you hear it more clearly on the VX.

Vs Noble Encore Custom: The Encore has a lighter bass presentation than the VX, but it is still a little bit more impactful than the Luna. Very close. I would not say the Luna is bass light in comparison though. The Luna shines in a bit softer and lighter presentation than the Encore that highlights Regina’s voice. I think the vocals are more open on the Luna. I would also say there is more detail on the Luna, but close.

So, on this track the Luna holds its own on all the IEM’s I listed except for the VX. The VX still seems to be in a different class, but that is as it should be as it costs more and is a custom. So, a good showing and the Luna has improved greatly.

I was asked by a headfier to listen to “I Know What I Know” from Paul Simon’s Graceland Album" and compare it to the others.

Vs Fourte: On this track I would say the bass is close and actually give the edge to the Luna. It sounds more detailed and tighter. Also, the overall presentation of the Luna is again more detailed, and you can hear different background vocals and sounds a little clearer. The driving bass hit rhythm is about equal on both. Close, but the Luna is the better listen.

Vs Anole VX Custom: Here again, the VX has more impact in the bass, and is a bit tighter and detailed. Very close though. However, the VX also provides a clearer sound to the overall presentation. You can also play it at lower volumes on the VX and maintain the excellent sound quality. The Luna wants to stay at a higher volume to sound its best on this track. The Luna does do a good job on the bass, the driving rhythm, and Simon’s vocals sound great on the Luna as well, but the VX has the edge.

Vs Noble Encore Custom: Here I liked the presentation of the Luna best. A more detailed bass and midrange that allows you to hear more into the music. The rhythmic drive of the Encore seems a bit congested as compared to the Luna. The Luna is the clearer sound.

Overall the Luna has come into its own. I do not know if it will improve more. I will let you all know if it does. And hopefully I can find more comfortable eartips with the same sound quality. By the way, all of these comparisons were done using my Cayin N8 in Tube mode. I have also listened to the Luna with my Hugo 2 and that is a great match. I mention that in case anyone was wondering. Tks.

 

[subguy812]

Entry 2 – 55 Hours of burn-in

Ladies and gentlemen, the bass has arrived! I would say not really because of the additional burn-in, but because of the changing of ear tips. And if I may be allowed to say it, the Luna is a pain in the ass when it comes to tips! The blue tips are the most comfortable to me, but also a bit bass light. When I move up to the large size (I am usually a medium) I can hear more bass. But still bass light in comparison to my final choice. Symbio tips work well, but I was not as comfortable in them as I like. I felt the spin fits were all bass light in my ears. The JVC Spiral Dots were not a match for me either. What worked the best for me? Final E tips in size L. Comply tips also worked well, but the Final are easier to put in and remove. There are some other recommendations as you all have read (The Azla SednaEarfit Light Short from SubGuy812 and Ranfan). I may try them in the future as well hoping for something more comfortable to me with the same sound (assuming I can find them).

The Luna now sounds really good, and I have provided a few comparisons below as examples.

Regina Spektor: Fidelity

Vs Fourte: The Fourte still hits a bit harder in the bass. But there is good bass in the Luna.
Both provide good air around her voice, maybe the Luna has a slight edge here. The Luna also has more detail than the Fourte. For example, when she sings the word “Heart” you hear the inflection of the “t” better. Both renditions are compelling.

Vs Anole VX Custom: The Luna delivers a lighter presentation. The bass hits harder, tighter, and with more detail on the VX. The VX has the edge in the midrange and treble as well. The VX provides a fuller presentation. You will hear the same detail, and a little different pitch in Regina’s voice (very slight) that is more accurate. There are times she changes the sound or inflection of her voice and you hear it more clearly on the VX.

Vs Noble Encore Custom: The Encore has a lighter bass presentation than the VX, but it is still a little bit more impactful than the Luna. Very close. I would not say the Luna is bass light in comparison though. The Luna shines in a bit softer and lighter presentation than the Encore that highlights Regina’s voice. I think the vocals are more open on the Luna. I would also say there is more detail on the Luna, but close.

So, on this track the Luna holds its own on all the IEM’s I listed except for the VX. The VX still seems to be in a different class, but that is as it should be as it costs more and is a custom. So, a good showing and the Luna has improved greatly.

I was asked by a headfier to listen to “I Know What I Know” from Paul Simon’s Graceland Album" and compare it to the others.

Vs Fourte: On this track I would say the bass is close and actually give the edge to the Luna. It sounds more detailed and tighter. Also, the overall presentation of the Luna is again more detailed, and you can hear different background vocals and sounds a little clearer. The driving bass hit rhythm is about equal on both. Close, but the Luna is the better listen.

Vs Anole VX Custom: Here again, the VX has more impact in the bass, and is a bit tighter and detailed. Very close though. However, the VX also provides a clearer sound to the overall presentation. You can also play it at lower volumes on the VX and maintain the excellent sound quality. The Luna wants to stay at a higher volume to sound its best on this track. The Luna does do a good job on the bass, the driving rhythm, and Simon’s vocals sound great on the Luna as well, but the VX has the edge.

Vs Noble Encore Custom: Here I liked the presentation of the Luna best. A more detailed bass and midrange that allows you to hear more into the music. The rhythmic drive of the Encore seems a bit congested as compared to the Luna. The Luna is the clearer sound.

Overall the Luna has come into its own. I do not know if it will improve more. I will let you all know if it does. And hopefully I can find more comfortable eartips with the same sound quality. By the way, all of these comparisons were done using my Cayin N8 in Tube mode. I have also listened to the Luna with my Hugo 2 and that is a great match. I mention that in case anyone was wondering. Tks.

I also posted this on another thread. I am glad to see you are enjoying the Luna. It is really a dynamic and lively listen. I have done an exhaustive breakdown of ear tips and musings on the Luna. Please read it here.
https://audiorabbithole.com/dunu-ramblings/

 

[darveniza]

As a friendly announcement, we've had a few users (who elected to use Type E tips) report to us the LUNA sometimes sounding "tinny with faraway vocals" on one side. It has sometimes led to quite a bit of alarm for some people, especially when they've only had their shiny new flagship for a couple of days.

We worked with these users to troubleshoot, and from preliminary experience of a small sample size of users, it is a fully reversible effect of the very soft surround reversing its physical configuration under a very tight seal. Please bear in mind that this effect may not be exclusive to Type E tips and is more a side effect of too tight a seal within the ear, stemming from the choice of ear tip, the depth of insertion, and the size of the user's ear canal. The more airtight the seal, the deeper the insertion, and smaller the ear canal, the less there is air for the driver to move, and if the LUNA gets pushed into the ear too quickly, most of that air gets evacuated, producing a vacuum seal in the remaining space of the ear canal, and affecting driver excursion. Luckily, this effect almost always reverses itself spontaneously (the polyurethane surround will pop back into shape from its deformed position), but to hasten its recovery, we've tried to get users to pull back on that vacuum seal really quickly before breaking seal. It sometimes takes a few tries to do, but has not failed to produce a positive result so far.

Please also bear in mind that most individuals will not experience this effect. As mentioned, out of the multitudes of LUNA customers that we have corresponded with, only a couple have reported this occurrence. Our engineer Andy is aware of this effect and we've arranged to exchange a unit from one of our customers to examine whether this effect only occurs due to unit-to-unit variations, but our current understanding tells us this is a user-specific issue pertaining more to seal and vacuum issues. From a macro perspective, we're fairly satisfied with our QC efforts so far, and we're getting within a half dB tolerance between sides. However, if you experience such an occurrence, please do contact us, via PM, or e-mail. We will work with you to resolve any issues you may encounter.

Thanks for this information I was suffering that yesterday with the left side using stock tips. So really the guidance is to avoid too much seal, and inserting these slowly has to avoid fast rush of air?