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Eartips - have a significant impact on an IEM's sound - Would like to fully understand the WHY - please what are the factors involved?

OK1

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I just had the most life changing experience, appreciating how different an IEM can sound, by changing the eartips. Went through this with two IEMs.

Now wondering, what are the factors that cause such significant changes? Cos if we know more about these, it can influence our choice of eartips, and we do not have to do trial and error.

I.e if we understood these factors, as consumers of these products, we could buy based on "science"/logic.

Considering that this has such a significant influence on what we hear, why is there far more focus on cables, DAC's, drivers, IEMs, when the eartip at the end of the audio chain, may have probably the most impact, on what we hear.?

Unfortunately I do not have a measurement rig, to demonstrate objectively, this assertion that eartips have a major contribution.

The factors I am taking a guess at, would be :

1. Bore size i.e the inner diameter, through which sound is propagated from the IEM into our ear

2. Length

3. Shape of the surround of the eartip, that touches our ear canal

4. Shape of the inner bore, straight, flared, etc.

5. Material or materials, from which the eartip is made, affecting the absorption of different frequencies

6. The hardness of the inner bore

7. The hardness of the outer surround.

8. Any reflections in the inner bore., also related to all of the above.

9. Fit - how airtight is the seal, in the ear canal. This one I am fairly sure of - a good seal improves the bass, but there is not really an exact science, to say how far is too far, and when is the seal too much. From practice I know - its a bit of a range, and somewhere in the middle sounds ok, too much and its too bassy, too little and its tinkly gone is the bass.

9.1 The fit of the outer bore, i.e how much air is leaking out from the point of contact with the ear canal.

9.2 The fit of the inner bore, i.e how much air is leaking out from the contact point between the nozzle and the eartip. In one case the TRI Clarion with the 7hz Zero 2, this inner bore seal is a bit loose, and I perceive that there is a loss of bass, compared to the STOCK RED eartips of the 7Hz Zero 2 - which has a tighter inner bore seal with the nozzle.

Makes me wonder are there any sealant liquids that one may wish to apply, on the contact points, with the nozzle and the ear canal, to improve the seal. E,g some kind of rub on, or spray on. Just thinking aloud.

Sadly, there really is not much information put out by the eartip manufacturers, on the impact of their eartips, on audio quality.

Furthermore when IEM manufacturers bundle eartips with their products, you are on your own, no real guidance. No instructions on how to use eartips properly, no guidance on which eartip to use for what. No proper listing of what each of the eartips was intended to achieve You are left to your own devices, and abandoned to your fate.

I really would want to get a solid grasp of every possible factor, so I can choose eartips, deterministically, not based on trial and error.

What do I know now. That I am fairly sure of, from my own testing of :

The stock RED tips that come with the 7Hz Zero 2 - against
The stock BLUE tips that come with the 7Hz Zero 2
The TRI Clarion Large

On the 7Hz Zero 2 IEM.

1. If all other things remain equal, a larger inner bore seems to improve the highs and reduce the lows, i.e larger bore, brighter sound

2. If the inner bore that holds on to the IEM nozzle, is made of stiffer material, it seems to make the sound brighter. But I have only tested 3 eartips so this is not conclusive, cos I can't make all the other factors related to the IEM, constant, while varying only the hardness of the inner bore.

Looking forward to an enlightening discussion, and getting to the bottom of this. Thanks in advance, for your contributions.
 
What I can contribute having wide ear canals is how good the tips seal extremely determines how good bass performance is. From no bass at all to pretty darn perfect with the same IEM. I ended up chasing large 3rd party ear tips in Jeff’s Internet 24/7.
With the same 7Hz Zero2 as you.
IMG_1280.png
 
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What I can contribute having wide ear canals is how good the tips seal extremely determines how good bass performance is. From no bass at all to pretty darn perfect with the same IEM. I ended up chasing large 3rd party ear tips in Jeff’s Internet 24/7.
With the same 7Hz Zero2 as you.View attachment 418774
Excellent - just what I needed.

Could you kindly add a link to the ear tip - or mention the brand name, and product name, so I can google it.

Thanks.
 
From my email trail it would be this:

MOONDROP SPRING TIPS Silicone Eartips × 1
XL
 
From my email trail it would be this:

MOONDROP SPRING TIPS Silicone Eartips × 1
XL
Those are my default tips for most iem . The XL size seems to be the hardest to find though and isn't featured in the mixed pack (SML) so trying requires buying a 3 pack .

Hifigo had some recently .

Great because soft , squishy and a bit sticky so if large enough , keeps a good seal .
 
What I can contribute having wide ear canals is how good the tips seal extremely determines how good bass performance is. From no bass at all to pretty darn perfect with the same IEM. I ended up chasing large 3rd party ear tips in Jeff’s Internet 24/7.
With the same 7Hz Zero2 as you.View attachment 418774
My experience shocked me. Made me wonder, why do I go chasing more IEM's in the search for a better sound, when probably more important could be finding the best IEM for my IEMs.
From my email trail it would be this:

MOONDROP SPRING TIPS Silicone Eartips × 1
XL
Thank you. Excellent. Thanks indeed.
 
Those are my default tips for most iem . The XL size seems to be the hardest to find though and isn't featured in the mixed pack (SML) so trying requires buying a 3 pack .

Hifigo had some recently .

Great because soft , squishy and a bit sticky so if large enough , keeps a good seal .

Indeed - not easy to find. Found them on Hifigo - Relieved. Ordered the XL. Looking forward to trying them out.

Not cheap, but if they turn out to be good, definitely worth the expense. Do not mind buying the 3 pack, cos I am likely to have at least 3 IEM's which I use at different times, also use to reference each other, so I get a more complete idea (hopefully) of what the neutral perspective of an audio track or stream, sounds like.

Thanks everyone here. Highly appreciated.

Happy to take a few more suggestions on EarTips, what I had in mind was to buy a few and experiment. Until the science of what works and why it works, and what each kind of eartip does, is properly explained, it seems to be a bit of trial and error, spray and pray. I do not mind spending a bit to get the best sound from an IEM, cos that's pretty much the only way I listen to audio now., or take calls, join meetings etc, IEM in the ear - almost all day.

We live only once, and I might as well have some luxury in what I am listening to. I've spent more on parking fines, than IEM's and eartips!... i.e we spend on all sorts of things we do not really enjoy, might as well spend a bit on something that brings true pleasure, good hearing.
 
While searching for EarTips, I ran into another rabbit hole, which I dare not pursue any further, at this time, cos it may never end.

Custom filters and dampeners and tweezer like implements to remove and fix them, in place. Wow - this can get quite geeky.
 
Eartips are fundamental in iems world since perfect seal is mandatory to get proper sound.
Given this for granted, looking for a defined scientific rule about them is impossible since all depend on personal ear canals shape and their interaction with dfferent iems body and nozzle shapes, so trial and errors is the only way we can follow.
Anyway there are some points that one have to learn just to not start from scratch for any different iem one can get, an for me they were:
- start with at least a couple of iems with different nozzle length\insertion depth: from there i learned the generally i need large or largest tips (> 12.5 mm width)
- once i established I need large tips, i found that generally for iems with longer nozzle and deep insertion I'm ok with 12.5-13.00 mm tips, while for iems with short nozzle\shallow insertion I need larger tips (13.5-14.00 mm)
- from there i get some pack of cheap but good tips, specifically:

TRN T Large (12.8 mm)
TRN T.png


Tri Clarion Large (14 mm)
Tri Clarion Mid (12.6 mm)

Tri Clarion.jpg


Kbear 07 Large (13.7mm)
kbear_07.jpg



A large slection of no brand super cheap tips from Aliexrpess from 12 to 13 mm and different shapes, they turned out useful in some specific situations.


With this selections i covered all the sizes i possibly need and different shapes and bore sizes, and use them an all iems i own, the only one still going with stock tips is 7Hz Zero that was immediately good with stock large tips (the yellow ones) and never ever tried with others.

Going further than this, for me, is over-complicating things, because, imho:
- tips must give the tightest seal possible, because FR measurements and consequent EQ are (or should be) made in this way
- once perfect seal is ensured for bass, tips shape and bore size can affect high frequency by some extent but it variate from iem to iem and, again, with our ear canals resonance, so using tips to "equalize" can be a way of convenience but it cannot be a certain scientific way.

Some reviewers do measurements with different tips, like listener, so one can see the impact on different iems and make an idea.
As an example, using Kbear 07 on the TE Zero:Red i had an impression of rolled off highs that later i found confirmed on his site:
graph.png


here the dip was huge, but in most cases the difference are subtle and difficult to hear.
 
While searching for EarTips, I ran into another rabbit hole, which I dare not pursue any further, at this time, cos it may never end.

Custom filters and dampeners and tweezer like implements to remove and fix them, in place. Wow - this can get quite geeky.
Yeah, the custom ones is probably where it's really at especially if you have far from average ear shape. I can't find it at the moment, but I read an article once about software for modelling custom hearing protection pieces based on a print which is taken from the ears first using a wax-like susbtance. Basically the software would, based on ear canal shape and size, first generate the shape for a proprer fit (hence seal) then calculate things like extra mass and bore dimensions needed to get a very flat response (as opposed to the standard hearing protection plugs which pretty much all have higher attenuation for higher frequencies hence causing the canonical muffled sound). These custom plugs also have the option of fitting IEMs to it.
 
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Eartips are fundamental in iems world since perfect seal is mandatory to get proper sound.
Given this for granted, looking for a defined scientific rule about them is impossible since all depend on personal ear canals shape and their interaction with dfferent iems body and nozzle shapes, so trial and errors is the only way we can follow.
Completely agree.
In my experience, large tips with a shallow fit of the IEM tends to work better (better seal) for me than smaller tips with deeper insertion. The exception being the Etymotics super deep insertion—works great with super isolation.
I have had good success with the Spinfit tips but again, this is entirely personal.

Ear tips are well named: tips… about what may work for you !!! :p
 
Completely agree.
In my experience, large tips with a shallow fit of the IEM tends to work better (better seal) for me than smaller tips with deeper insertion. The exception being the Etymotics super deep insertion—works great with super isolation.
I have had good success with the Spinfit tips but again, this is entirely personal.

Ear tips are well named: tips… about what may work for you !!! :p
I'll second all of that. I must have large ear canals and like @mc.god and yourself need different tips for deep vs shallow styles. Moondrop spring tips xl for deeper and typically azla xelastec large for when the tip needs to secure to the entrance to the canal.

Very very rarely do any stock tips work for me. Tend to either be too firm and/or too small. Big and sticky ftw.
 
After trying some of the most popular ones for a while I recently settled with the Kbear07 large or similar larger than "normal" ones, I realized that some of the ones I've been using can start to have sealing problems with movent or moisture after some time and I had to adjust them (push the IEM in) constantly, I was so used to it that I didn't realize that with better fitting ones I don't have to. The Tri-Clarion Large works well for some IEMs too.

After I realized I have bigger ear canals I started to check measurements before ordering new ones, I haven't bothered with the most expensive ones (mostly because of their snake oil marketing) but I might start checking the larger ones.
 
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I think the following addresses the O.P.'s core issue, but I won't refer to their numerical itemizations.

The iem nozzles, the iem "tips" and the 2 distinct ear canals comprise an acoustic chamber. The interior configuration (which may entail differences between one's ear canals) such as diameter and length determines the inherent vibration frequency of the chamber.

Music in the iem created chamber resonates the air there. However, wearing iems creates a closed chamber and not an open chamber. There are more frequencies resonating in a closed chamber than an open chamber. And these are not pure sinusoid (sine) sound waves so iems generate overtone harmonics.

There is an additional factor of the time duration of any one chamber resonance's cycle when air (sound) naturally springs out past the iem tip's opening (end of tip). After executing about 1/2 of a resonant vibration cycle the chamber actively takes air ( sound) rebounding from the ear drum into the chamber.

That air (sound) rebounding from the ear drum pushes the back within the chamber and that creates additional resonance. That resonance transfers pressure farther down the chamber toward the iem nozzle. And with more air (sound) delivery from the iem through it's nozzle that overcomes the resonance pushing back toward the nozzle. This allows fresh air (sound) inside the chamber to move toward the iem ear tip's exit.

The newly produced music's air (sound) moving outward created transitory decompression inside the iem nozzle and ear tip body creates oscillations as it strikes the sides of the ear tip's body and opening end tip. The by-product of this interaction causes vortexes of air (sound) during passage toward the ear drum at the far side of the auditory chamber.

The more rigidity to the chamber the faster the air (sound) moves along favoring higher frequencies. We can see this in adult women who have, size for size, about 13% shorter ear canals anatomically than men; which means their ear canals are relatively more rigid. As women age they can (statistically) hear sound frequencies of 2,000 Hz and up better than men, yet hear less bass than men.

Narrow chambers (and narrow bore iem ear tips) such as being selectable by the inner diameter of an iem ear tip (and/or one's anatomy), get faster air (sound) flow in the center air portion than the rest (main) air column. Whereas wide chambers (and wide bore iem ear tips) promote relatively less center portion air flow.

So we have contributing factors like chamber rigidity, length, back resonances, inherent resonances and aperture.
Yet the operating principle is that when there's air (sound) frequencies which correspond to any resonant frequencies that synchronicity adds amplitude to the air (sound) and leads to greater (increased) sound strength at the ear drum.

The further an iem ear tips end tip goes into the ear canal the shorter the auditory canal, which alters chamber resonance from ear drum bounced back air (sound) and intrinsic chamber resonance. This reduces the higher frequencies impact and over tones inside the chamber (of which the iem ear tip's body is a big part). The iem output of bass is not changed, it is just heard more relative to higher frequencies because the high frequencies resonance is reduced - because the air (sound) dynamic inside a closed chamber is different than in an open chamber.

As for iem ear tip "seal" improves bass: the iem with a poorly sealed ear canal alters the closed auditory chamber. This causes inherent resonance within the chamber and interaction with back resonance from the ear drum to change. Again, to get greater (increased) sound strength the iem bass output has to resonate in synchronicity with chamber resonance. Seal the iem ear tip at the ear and you create more auditory chamber frequencies for the iem's output of bass to resonate with yielding louder (increased) bass inside the chamber ending at the ear drum.

I am going to recommend the "Tangzu Tang Sanchai" soft iem ear tips which I like for my planar dynamic iem. They have a soft end tip that delves (shortens auditory chamber)!readily into my 2 different interior contour ear canals and limit a sector of chamber rigidity that otherwise favors high frequencies over bass. Their tip end take vortexes into account reducing their linear impulses toward the ear drum lessening impacting wave distortion. ear tips' core is thick which preserves that sector's resonances. The core is also lined along the inner wall with vertical grooves which accelerates the lateral (side) airflow (sound) to better match central air flow which reduces distortion. These ear tips' outer surface is textured for superb gripping in place sealing the ear canal. I never tried their narrow bore and I still hear great jazz bass on my planar iems every time am streaming in CD quality.

IMG_1969.jpeg
IMG_1971.jpeg
IMG_1972.jpeg
 
Thanks everyone. Highly appreciated, all contributions to this topic.

A bit off topic.

Having made an effort to improve all my IEMs via tip rolling, I come to a life changing conclusion. I am abandoning the budget category of IEMs, the more revealing I hear them, the more I face the truth, they cannot compete. I have at this time the following budget IEMs. CCA Polaris, CCA CRA, KZ EDC Pro, 7Hz Zero 2, but as soon as I hear the ARTTI T10, no contest, a totally much better result. Far more accurate. I've been listening for months, and I do not know if driver break in(burn in), is true or not, or if it's my own ears that needed to be broken in(burnt in). The conclusion, is final. No more budget IEMs. It's like a budget car, they simply do not have the kind of acceleration, you get in a more powerful engine.

We live only once, why subject ourselves to mediocre sound.

I've been hearing the difference for months, but yesterday it came to a head. I was listening to some gospel music - More than Anything, Lamar Campbell and others. We are familiar with how voices should sound, and for this kind of music, they are careful, NOT to distort the vocals, through tons of "compression" or other dynamics processing. Furthermore there is a complexity, hearing lots of voices at the same time.

I am reminded of the ethos behind the Harbeth (BBC inspired) Hi-Fi/Studio speakers, which was natural reproduction of the human voice. It was so apparent like chalk and cheese, huge difference - the budget IEMs, mangled the vocals, making them sound like aliens, the ARRTI T10 - just lifelike, the most natural. That was my conclusion. like mirror mirror on the wall, only one of these IEMs was telling me the truth, and that was the ARRTI T10.

Why the hesitation, why did it take me so long to - fully accept this, self doubt. Also I've listened to dynamics headphones or earbuds and now IEMs, all my life, that is what I know, so hearing something else seemed strange, and "wrong". But it's now conclusive, no more budget single DD IEMs. I will still keep them for nostalgia purposes, or as backups. Or as a way to reference what listeners with budget devices, will hear, of the music/audio, which I work on in my studio. But for my critical or pleasurable personal listening, no more budget IEMs. Not worth the economy or savings. You just keep buying more and more of the cheapies, but the solution is to stop and spend the money on something that is truly excellent like the T10.

The biggest challenge is, there are no clearly articulated measurements that I know of, that will tell anyone that the T10 sounds better than these cheapies. None. So as much as this web site AudioScienceReview, makes some effort - apologies, it is a bit of a waste of time. Those measurements reveal nothing about exactly how a headphone or IEM will sound. I say this with all due respect, not out of disregard, but we are not yet there. My hunch is maybe there is information available in the group delay and impulse response measurements, but these are not consistently published here in IEM reviews. Also maybe there is information in the Waterfalls. So the only real way we can anticipate how a headphone device will sound, is to take the word of reviewers. Especially where there is consensus.

But herein lies the dilemma - there is also consensus, that the 7Hz Zero is a good sounding device, and I agree, but only in context of similar budget devices, not a giant killer, but it's hard in the plethora of favourable opinions, to appreciate the context, of the positive views - good - for the price. I think price should no longer be a consideration, simply compare products based only on quality, and let the buyer determine how much they are willing to spend, not the other way round where we pigeon hole products into price segments. If the audio quality is the priority, forget about price, rank devices based on perceived quality, and the only way we have today of doing this really is subjective. The Zero 2 and the ARTTI T10 have somewhat similar Frequency Responses, but nothing I know at this point in time, explains the huge difference in sonic accuracy. At least nothing in the Frequency Responses.
 
Thanks everyone. Highly appreciated, all contributions to this topic.

A bit off topic.

Having made an effort to improve all my IEMs via tip rolling, I come to a life changing conclusion. I am abandoning the budget category of IEMs, the more revealing I hear them, the more I face the truth, they cannot compete. I have at this time the following budget IEMs. CCA Polaris, CCA CRA, KZ EDC Pro, 7Hz Zero 2, but as soon as I hear the ARTTI T10, no contest, a totally much better result. Far more accurate. I've been listening for months, and I do not know if driver break in(burn in), is true or not, or if it's my own ears that needed to be broken in(burnt in). The conclusion, is final. No more budget IEMs. It's like a budget car, they simply do not have the kind of acceleration, you get in a more powerful engine.

We live only once, why subject ourselves to mediocre sound.

I've been hearing the difference for months, but yesterday it came to a head. I was listening to some gospel music - More than Anything, Lamar Campbell and others. We are familiar with how voices should sound, and for this kind of music, they are careful, NOT to distort the vocals, through tons of "compression" or other dynamics processing. Furthermore there is a complexity, hearing lots of voices at the same time.

I am reminded of the ethos behind the Harbeth (BBC inspired) Hi-Fi/Studio speakers, which was natural reproduction of the human voice. It was so apparent like chalk and cheese, huge difference - the budget IEMs, mangled the vocals, making them sound like aliens, the ARRTI T10 - just lifelike, the most natural. That was my conclusion. like mirror mirror on the wall, only one of these IEMs was telling me the truth, and that was the ARRTI T10.

Why the hesitation, why did it take me so long to - fully accept this, self doubt. Also I've listened to dynamics headphones or earbuds and now IEMs, all my life, that is what I know, so hearing something else seemed strange, and "wrong". But it's now conclusive, no more budget single DD IEMs. I will still keep them for nostalgia purposes, or as backups. Or as a way to reference what listeners with budget devices, will hear, of the music/audio, which I work on in my studio. But for my critical or pleasurable personal listening, no more budget IEMs. Not worth the economy or savings. You just keep buying more and more of the cheapies, but the solution is to stop and spend the money on something that is truly excellent like the T10.

The biggest challenge is, there are no clearly articulated measurements that I know of, that will tell anyone that the T10 sounds better than these cheapies. None. So as much as this web site AudioScienceReview, makes some effort - apologies, it is a bit of a waste of time. Those measurements reveal nothing about exactly how a headphone or IEM will sound. I say this with all due respect, not out of disregard, but we are not yet there. My hunch is maybe there is information available in the group delay and impulse response measurements, but these are not consistently published here in IEM reviews. Also maybe there is information in the Waterfalls. So the only real way we can anticipate how a headphone device will sound, is to take the word of reviewers. Especially where there is consensus.

But herein lies the dilemma - there is also consensus, that the 7Hz Zero is a good sounding device, and I agree, but only in context of similar budget devices, not a giant killer, but it's hard in the plethora of favourable opinions, to appreciate the context, of the positive views - good - for the price. I think price should no longer be a consideration, simply compare products based only on quality, and let the buyer determine how much they are willing to spend, not the other way round where we pigeon hole products into price segments. If the audio quality is the priority, forget about price, rank devices based on perceived quality, and the only way we have today of doing this really is subjective. The Zero 2 and the ARTTI T10 have somewhat similar Frequency Responses, but nothing I know at this point in time, explains the huge difference in sonic accuracy. At least nothing in the Frequency Responses.
I'm sorry but nothing in your (many) posts on this is worth much of anything to anybody else. Which is why we like to start with objective data rather than anecdote. Just as recently as a week ago you flopped the other way. https://www.audiosciencereview.com/...crinacle-zero-2-iem-review.50534/post-2178495

Today you prefer the T10. Good for you. They don't measure the same as the z2, not on a rig and surely not in anyone's ears.

I can't really get on with the z2 too well. The shape and fit aren't really for me which means I haven't spent too long trying to get the best eq profile. The T10 stock were just a bit too spicy for me but I got on with the physical aspects better.

Everyone should sample a well tuned cheapo like the Z2 to see what can be had. It's low distortion means you can easily experiment with eq and make it tonally akin to for eg a t10. The t10 can now be had for around double the price but I'm not sure I'd advise anyone to get it as a starter. Or even a second pair.

You are, frankly, chasing ghosts. If you had to go out and spend £100 on an iem on pain of death, and that would be the only pair you could ever listen to how would you go about doing that?
 
I have a pair of 7Hz x Crinacle Zero:2. They're fantastic but I'm using the red tips (the largest) and I need to constantly push them in to get a good seal otherwise the base starts to fade away. Is there a recommended replacement I can use? How will I know any given pair will fit this IEM? I have the feeling these ones would be fine if they were more rubbery/sticky!
 
How will I know any given pair will fit this IEM?
It's rare that an aftermarket set of tips don't go on an IEM at all. Worst that can happen with a bad fit is that you'd either have to apply some force when attaching the tip to the IEM or that the tip can get prone to getting stuck in your ear when you take the IEM off. I haven't had any issues with any aftermarket tips on the Zero:2.

As for fit, as others have said - it's personal what works for you. The Tri Clarion mentioned earlier in the thread works for me with this IEM, YMMV.

I am going to recommend the "Tangzu Tang Sanchai" soft iem ear tips which I like for my planar dynamic iem.
...
I never tried their narrow bore and I still hear great jazz bass on my planar iems every time am streaming in CD quality.
These tips are also available in a wide bore version, and they're quite different from other tips I've tried. The tip is very short and so the IEM sits quite deep. I find that this works very well but the deep pressure can be fatiguing during longer listening sessions.
 
Having made an effort to improve all my IEMs via tip rolling, I come to a life changing conclusion. I am abandoning the budget category of IEMs, the more revealing I hear them, the more I face the truth, they cannot compete. I have at this time the following budget IEMs. CCA Polaris, CCA CRA, KZ EDC Pro, 7Hz Zero 2, but as soon as I hear the ARTTI T10, no contest, a totally much better result. Far more accurate. I've been listening for months, and I do not know if driver break in(burn in), is true or not, or if it's my own ears that needed to be broken in(burnt in). The conclusion, is final. No more budget IEMs. It's like a budget car, they simply do not have the kind of acceleration, you get in a more powerful engine.
Oh no, not again! o_O

You are, frankly, chasing ghosts.
Couldn't express this better.
 
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