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Topic: Can IEMs be as good as full sized headphones? (Read 303765 times) previous topic - next topic
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Can IEMs be as good as full sized headphones?

I've been using full sized headphones for a long time.  Lately (over the last few years), it seems like just about everybody and their brother is releasing IEMs.  I realize there is a large profit motive to do so because of the explosion of portable media devices.  For a long time I've simply dismissed them as devices that sacrificed sound quality for size and portability.

However, it seems like IEMs are changing and improving by leaps and bounds.  It's quite easy to find multiple driver IEMS, and one new device even has 6 balanced armatures!  Considering the size of the drivers, I assume they have physics (less inertia) in their favor in comparison to the large diaphragms of full sized headphones.

Certainly, it seems there is a lot more actual technological changes in the IEM world than in the full sized headphone world.

Does anybody have any person experiences comparing IEMs to full size headphones? Would your replace your full sized headphone with an IEM?  How is the sound in terms "in your head?"  What other comments do you have?

It really intrigues me to think that an IEM could best a full sized headphone.  I think I'd gladly ditch my full sized cans if IEMs did this with the comfort of a full sized headphone.

I realize I should ask these questions on one particular website that is more inclined to this topic.  But that site has way too much fantasy and it's hard to separate truth from placebo.

Can IEMs be as good as full sized headphones?

Reply #1
one new device even has 6 balanced armatures!

Do you mean 3 in each enclosure?

In any case, I've been very happy with IEMs. Comfort is probably the biggest issue, but certainly no complaints for sound. I've tried Westone UM2, Shure E4, E500 (SE530), SE420, Ultimate Ears Super.fi 5EB. Full-sized headphones haven't been too interested. I've tried briefly the Bose Triport (very comfortable, don't know about sound quality) and I have Grado SR80's which I only use when I need to hear what's going on outside. Bass is lacking compared to all the IEMs above, and it's a tad too bright for my taste, but you get used to it after a while.

After testing all those IEMs, my favorites are the Westone UM2. I even bought them twice, cause I got rid of the first ones I bought. I sold the E500's cause they were pretty redundant, and for the price the build was finicky. My first pair had one of rubber cable holders break off easily, luckily I could claim warranty, but never used them again. Also sold the E4's, and now I keep the UM2, the SE430 (for no particular reason, I just like to keep them around, they look very cool too and the design is much better than previous generation E500) and the Super.fi 5EB for movies. The SF has wicked deep and strong bass.

Can IEMs be as good as full sized headphones?

Reply #2
I  got one full-sized headphones: sennheiser hd595
And one IEM: sennheiser ie7.

This IEM, use a dynamic driver, unlike majority of IEMS  that are balanced armature.
Most likely this means  better bass, and less analytical sound.

I find the sound from the full-sized headphone more neutral, natural, and detailed.
Nevertheless, I  won't use my HD595  with my portable mp3, nor sleep with them on my ears 

I'm pretty satisfied with my IEM, and I  don't care if my full-size headphone might have better sound quality.
This is just enough for me to enjoy every kind of music. And that's all what matters to me.
With cheap ipod earbuds, some music are unlistenable (example : emilie simon, album vegetal).

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However, it seems like IEMs are changing and improving by leaps and bounds. It's quite easy to find multiple driver IEMS, and one new device even has 6 balanced armatures!

There's no proof that more balanced armatures always means better sound. It certainly means more expensive. The recent phonaks, are single balanced armature, and are quite popular at head-fi.
Don't forget that single balanced armature are evolving too ..

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Would your replace your full sized headphone with an IEM?

No, sound signature is not exactly the same, and I enjoy both differently.

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It really intrigues me to think that an IEM could best a full sized headphone. I think I'd gladly ditch my full sized cans if IEMs did this with the comfort of a full sized headphone.

Sometimes IEMs  can be uncomfortable too...  If you listen more than hour , with them stuck on your ears, you might have enough of them. Because your ears need to "breath".

Can IEMs be as good as full sized headphones?

Reply #3
one new device even has 6 balanced armatures!

Do you mean 3 in each enclosure?


6 in each enclosure!  The JH Audio 13 Pro is the recent favorite at that unnamed headphone site, but at $1099 it's quite a bit out of the price range I could seriously consider.  People are making all sorts of claims about them including them having the soundstage (read, out of head experience) of full sized headphones.  They are the current favorite, assuming you can afford them.

Let it be known that I have no affiliation with JH Audio, I have never heard any of their gear, and am not offering any sort of recommendation for their stuff.  It's just that the claims about them have got me wondering about the capabilities of IEMs.

I've heard about the Westone UM2.  I'm currently considering them and the UM3X, just because they are supposed to have a fairly neutral sound.

Thanks for the info.

Can IEMs be as good as full sized headphones?

Reply #4
Well that 6-driver thing just seems blatantly overkill. The Westone 3 seem like a bargain then.

Can IEMs be as good as full sized headphones?

Reply #5
In my experience the Sennheiser IE 8's seem much better than the same company's HD555's or the noise canceling PCX 450's, considering only pure sonics.  They really sound quite fabulous and, to me, listening to my iPod with them feels like a genuine high end experience.  The imaging is really quite spectacular though, of course, hardly natural.

BUT: when wearing them the sounds of chewing and swallowing are made so prominent that I really can't eat anything comfortably with them on, and they also often make my pulse disconcertingly audible.  So I often turn to the others instead.  Now that the weather is cooling I usually take the 450's on the bus with me because the sound is pretty good and the noise canceling helps with the road roar.

But only the IE8's give me that "high end thrill".

So I would say that some IEMs can sound better than some expensive over the ear headphones.  How the IE8's would compare with the HD 650's or 800's is beyond the power of my wallet to know.
Ed Seedhouse
VA7SDH

Can IEMs be as good as full sized headphones?

Reply #6
I've owned the Shure E4 and E500, and I had a bad experience.  My oddly shaped ear canals may have had something to do with this, but the bass rolloff in the E500 and the bass and treble rolloffs in the E4 put the E4 somewhere below ipod earphones for me and the E500 somewhere between those earbuds and all of the full-sized headphones I can remember owning (which are too many).  I don't believe my experience is representative of that of most listeners, however.

I've been a longtime head-fier and am very pleased to have finally found this forum, which seems free from all of the BS that poisons head-fi and the other forums I've frequented, and expect, for that reason, that it will it will be much more useful to me.  That said, I've been on head-fi a lot recently and the buzz surrounding the JH13 seems so widespread an unanimous that I think there's actually something to it.  From what people have been saying, it seems like its better frequency response, together with its being a custom IEM (like I said, I had serious fit issues), might rectify all of the problems I had with universals.  I think I'm going to give the JH13 a try.

Can IEMs be as good as full sized headphones?

Reply #7
There's no proof that more balanced armatures always means better sound. It certainly means more expensive. The recent phonaks, are single balanced armature, and are quite popular at head-fi.
Don't forget that single balanced armature are evolving too ..


At least IEMs are evolving, which is a much more than can be said for full sized headphones.  But it's hard to know why exactly manufactures are increasing the number of armatures in a IEM.  Consumers may assume that it's purely for "sound quality" but certainly manufacturers have many things to consider including the marketing of 3 drivers versus 1.

Compare this to full sized headphones.  It seems like manufacturers have been just changing sound signatures for 10+ years and just making marketing claims.  Senn quite literally made a cosmetic change to the HD580 and started charging quite a bit more for the HD600.  There are some recent exceptions with the driver designs of the Senn HD800 and Beyer T1, but it's hard to separate fact from fiction in reviews and marketing.

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In my experience the Sennheiser IE 8's seem much better than the same company's HD555's or the noise canceling PCX 450's, considering only pure sonics.


What about in terms of "soundstage."  After trying a lot of headphones I've come to appreciate the sense that I'm listening in a wide space (compared to earbuds), albeit a space that is still much smaller than you get from speakers.  Some headphones have a very flat sound.  How does the IE8 compare to the HD555 in this regard?

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Well that 6-driver thing just seems blatantly overkill. The Westone 3 seem like a bargain then.


It would be nice to know how all this works.  Is 6 really better than 3 or is it just marketing?  Is it another 5.1,7.1,9.1,11.1 game?  Do musicians really pay $1K+ for an IEM? 

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That said, I've been on head-fi a lot recently and the buzz surrounding the JH13 seems so widespread an unanimous that I think there's actually something to it.


It's hard for me to tell.  In the past many headphones have seen as the greatest gift to audioland.  Any negative comments were seen as the rantings of a person with defective hearing.  But, a year later, some of these same headphones are almost universally panned.  Any claims of their perfection are seen to be made by people with defective hearing!

So I don't know.  $1100 is a lot of money of a custom IEM that probably cannot even be resold or returned.

Can IEMs be as good as full sized headphones?

Reply #8
@odigg

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6 in each enclosure! The JH Audio 13 Pro is the recent favorite at that unnamed headphone site, but at $1099 it's quite a bit out of the price range I could seriously consider


The custom utimate ears 11, are around the same price. But they are only four balanced
armature, so for the price you get "less" (just kidding)
The high end earsonics have also similar price,  but only with three balanced armatures ...

The big price does also from that they are all "customs molded iems", same for JH13.
You have to add at least 500$, to get customs.

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Senn quite literally made a cosmetic change to the HD580 and started charging quite a bit more for the HD600.

The hd6xx serie need an amplifier to get the best of them (according to head-fi comments),
while hd5xx not, so I  guess there's more than a cosmetic change.

Quote
What about in terms of "soundstage."

If you want the IEMs  with the best "soundstage" , take Sennheiser simple as that.
When I  listen to my IE7, the "3d sound" can be incredibly immersive.
On some music this can be even disturbing: "Did someone open the door?
No this just comes from the music I  listen".


Quote
Is 6 really better than 3 or is it just marketing?

Here's how I  would explain things:
each balanced armature reproduce more or less faithfully a range of frequency.
The better are the balanced armature you use, the less you need to use
multiple balanced armature to cover faithfully all frequencies.
I  guess each Brand are using their own "proprietary" balanced
armature, so according to their lab experiments, they might need more or less
balanced armature to reach the sound quality they are expecting.
Off course, I guess there's some marketing.  I'm quite skeptical
for the need of 6 drivers.

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Do musicians really pay $1K+ for an IEM?

The big price is more justified by the fact they are customs,
than the big number of balanced armatures.

Can IEMs be as good as full sized headphones?

Reply #9
Here are my comments:

IEMs and headphones can both sound great.

IEMs give you isolation which gives you improved S/N in many situations. Improved S/N is improved S/N - doesn't matter to me whether it is from cleaner electronics, more bit resolution or a good seal in the ear. (This also makes them dangerous for use while jogging etc.)

Headphones can give me a more stable sense of bass. If you're moving around with IEMs in, you hear a lot of low frequency interference from the movements of your body. You don't hear so much of that when you're ears are open into headphones.

I personally would like to know what is the justification for the existence of iPod style ear buds. I see people using these things on airplanes and subways and I'm thinking that either they can't hear the music/dialog or they have them cranked dangerously high. They hurt my outer ear too but apparently that's mostly just me. All I can figure is that they're popular because they're small and cheap.

 

Can IEMs be as good as full sized headphones?

Reply #10
@Notat
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Headphones can give me a more stable sense of bass.

The iems have to be "sealed" properly with your ears, to get correct bass.
You have usually to test all the tips provided with your iems, to see wish one fit the best
for your ears. And for some people that's not enough, they buy separate tips
from different brand.

Usually "dynamic driver" reproduce deeper bass than balanced armature,
and I think they are less problematic if you don't get proper "seal".

Quote
If you're moving around with IEMs in, you hear a lot of low frequency interference from the movements of your body.

Commonly the word "microphonics" is used to describe this.
Some iems have more microphonics than others;  usually high end iems minimize this problem.

Quote
I personally would like to know what is the justification for the existence of iPod style ear buds.

Many people are just "satisfied" with whatever is provided with their mp3 player.
Also if they ear buds broke ,  they look for something similar.
One thing that is nice with cheap ear buds, is that you are not too much afraid to break them accidentally.

Can IEMs be as good as full sized headphones?

Reply #11
I love my Sennheiser CX500's.  Great sound quality IMO, less than $100 price tag and great for use with portable players.
JXL

Can IEMs be as good as full sized headphones?

Reply #12
The idea behind 2 and 3-way IEMs is that balanced armatures have a very limited frequency response, so this improves things.  Pretty simple.  As for the reasoning behind having more than one identical driver, Jerry Harvey of JH Audio said something about this.  Unfortunately I won't be able to find the quote, but basically he said that these balanced armatures distort more at higher SPL.  By using two drivers for each frequency range, as is the case with the JH13, the SPL of each driver can be halved at the same volume level for the listener.  He made a reference to how at big concert venues, speakers use lots of smaller drivers, rather than one huge one.  It's the same principle.

Jerry Harvey founded Ultimate Ears and designed their custom line, then sold the company to Logitech and founded JH Audio.  He confined the new company to the aviation business for a while, but recently returned to pro and consumer audio with redesigns of Ultimate Ears' line.

$500 extra is way too high an estimate of the premium you pay for going custom.  JH Audio's JH5 Pro only costs $399, and there are even less expensive IEMs from other manufacturers.  You can get custom earpieces for universal IEMs for around $100-200.  Keep in mind that you will be paying for the audiologist appointment as well, which should cost around $50-$150.

I've never heard of the HD580 being identical to the HD600 aside from cosmetics and doubt they are, but a few head-fiers saying that one is hard to drive and one is easy to drive is hardly a reason to believe that they aren't the same.  Those people are crazy.

Can IEMs be as good as full sized headphones?

Reply #13
Quote
In my experience the Sennheiser IE 8's seem much better than the same company's HD555's or the noise canceling PCX 450's, considering only pure sonics.


What about in terms of "soundstage."  After trying a lot of headphones I've come to appreciate the sense that I'm listening in a wide space (compared to earbuds), albeit a space that is still much smaller than you get from speakers.  Some headphones have a very flat sound.  How does the IE8 compare to the HD555 in this regard?


Well, I turn the bass control all the way up.  To me they then seem to be flat down to the deepest notes I have on any recording, but others complain about "mid bass bloat" that way.  We really don't yet know the "correct" response for headphones of any type to give an audibly flat response, it seems. 

The IE8's seem to float left and right channels a few inches outside my head, and on the occasional bit of binaural sound effects (such as on the children playing sounds after track 5 of "The Wall") they seem to float sounds quite a few feet to the left and right (but not ahead).  The image is very pleasing to me, but not really "natural".  I get no sense of sounds coming from in front of me, for instance.

I have not double blinded these or any other phone against anything, so take my impressions with that in mind.  Your mileage may vary!  On the other hand that different speaker-end transducers usuallly sound audibly different to one another is, I believe, not controversial.

Ed Seedhouse
VA7SDH

Can IEMs be as good as full sized headphones?

Reply #14
Unfortunately I won't be able to find the quote, but basically he said that these balanced armatures distort more at higher SPL.  By using two drivers for each frequency range, as is the case with the JH13, the SPL of each driver can be halved at the same volume level for the listener.


This makes me ask another question. What SPLs are we talking about?  Are 3 driver designs audibly distortion free at hearing damage levels?  If so, what's the point of making them distortion free at even higher SPLs?

Quote
I've never heard of the HD580 being identical to the HD600 aside from cosmetics and doubt they are, but a few head-fiers saying that one is hard to drive and one is easy to drive is hardly a reason to believe that they aren't the same.


I believe the HD580 and HD600 share the same drivers and, at least to my eyes, a nearly identical (or identical) headband design.  The grills for the HD600 are metal and Senn claims the drivers are better matched.  So if the HD600 is basically the HD580 with a metal grill, I'd judge it as a cosmetic upgrade.  I recall the grills being a whopping $20.  The HD600 sells for twice what the HD580 sold for when new.

I don't mean to argue with you about this and I'm content if somebody demonstrates I'm talking out of my rear.

Can IEMs be as good as full sized headphones?

Reply #15
@steaxauce
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The idea behind 2 and 3-way IEMs is that balanced armatures have a very limited frequency response, so this improves things.

That doesn't seem true with the recent phonaks for instance. People seems satisfied with them, for lows, mids, and highs. I rather have a recent iem model  with single balanced armature, than an old one with two balanced armature, because the technology is evolving.


Quote
Unfortunately I won't be able to find the quote, but basically he said that these balanced armatures distort more at higher SPL.

I didn't hear of the problem of distortion at high volumes, with dynamic drivers. That's an additional motivation for me to prefer dynamic drivers over balanced armatures.

Quote
By using two drivers for each frequency range, as is the case with the JH13, the SPL of each driver can be halved at the same volume level for the listener.

Then there's also the problem of interferences . That's not obvious.

Quote
$500 extra is way too high an estimate of the premium you pay for going custom. JH Audio's JH5 Pro only costs $399, and there are even less expensive IEMs from other manufacturers. You can get custom earpieces for universal IEMs for around $100-200. Keep in mind that you will be paying for the audiologist appointment as well, which should cost around $50-$150.

Most of the time , the overall cost for going to customs is $1k+
And I wouldn't be surprised  that each brand are boosting the price for the high end  models (i.e models that allow customs) ,  as much as they can. Because they are reserved for the "audiophile elite" (put any joke here).

Can IEMs be as good as full sized headphones?

Reply #16
Unfortunately I won't be able to find the quote, but basically he said that these balanced armatures distort more at higher SPL.  By using two drivers for each frequency range, as is the case with the JH13, the SPL of each driver can be halved at the same volume level for the listener.


This makes me ask another question. What SPLs are we talking about?  Are 3 driver designs audibly distortion free at hearing damage levels?  If so, what's the point of making them distortion free at even higher SPLs?

I honestly don't know, but I think it would be a jump to assume that 3-driver designs have inaudible distortion levels at normal listening levels.  All I can say is that, from what JH said, it seems that they perform better at lower SPL.

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The idea behind 2 and 3-way IEMs is that balanced armatures have a very limited frequency response, so this improves things.

That doesn't seem true with the recent phonaks for instance. People seems satisfied with them, for lows, mids, and highs. I rather have a recent iem model  with single balanced armature, than an old one with two balanced armature, because the technology is evolving.

I may have to look into those Phonaks; I hadn't heard of them.  Some armatures have better frequency responses than others, of course, but this nevertheless is the idea behind having a crossover network with multiple drivers.

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Unfortunately I won't be able to find the quote, but basically he said that these balanced armatures distort more at higher SPL.

I didn't hear of the problem of distortion at high volumes, with dynamic drivers. That's an additional motivation for me to prefer dynamic drivers over balanced armatures.

That they have lower distortion at lower volumes doesn't mean they have particularly bad distortion at higher volumes.  It's pretty much impossible to extrapolate what a completely different technology will sound like based on measurements and design info.  Better to stick to listening tests.

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By using two drivers for each frequency range, as is the case with the JH13, the SPL of each driver can be halved at the same volume level for the listener.

Then there's also the problem of interferences . That's not obvious.

He just implied that the SPL would be lower with multiple drivers.  I extrapolated that it would be halved without thinking about interference, so I apologize for that.  Though, since the two drivers are adjacent to each other and in phase, it would seem that they would only interfere constructively.

Quote
$500 extra is way too high an estimate of the premium you pay for going custom. JH Audio's JH5 Pro only costs $399, and there are even less expensive IEMs from other manufacturers. You can get custom earpieces for universal IEMs for around $100-200. Keep in mind that you will be paying for the audiologist appointment as well, which should cost around $50-$150.

Most of the time , the overall cost for going to customs is $1k+
And I wouldn't be surprised  that each brand are boosting the price for the high end  models (i.e models that allow customs) ,  as much as they can. Because they are reserved for the "audiophile elite" (put any joke here).

My guess is that pricing would be more based on what they can be marketed for than what they cost to produce, but custom IEM makers target professional musicians more than audiophiles (or at least it used to be that way).  The pros are generally a lot more sensitive to BS than the audiophools who buy such things.

Can IEMs be as good as full sized headphones?

Reply #17
Quote from: Notat link=msg=0 date=
If you're moving around with IEMs in, you hear a lot of low frequency interference from the movements of your body.

Commonly the word "microphonics" is used to describe this.
Some iems have more microphonics than others;  usually high end iems minimize this problem.

Microphonics is translation of vibration into electricity. The effect I experience is a telegraphing of vibration into my ears - there's no electricity involved. I use Etymotic ER-4's. How much more high end do I need to go?

Can IEMs be as good as full sized headphones?

Reply #18
Microphonics is translation of vibration into electricity. The effect I experience is a telegraphing of vibration into my ears - there's no electricity involved. I use Etymotic ER-4's. How much more high end do I need to go?


My Sennheiser IE8's exhibit the same effect, bur I don't know if they come in above or below your Ety's in the expensiveness sweepstakes.  I believe the effect is caused by bone conduction and is not a microphonic effect, whatever they call it.
Ed Seedhouse
VA7SDH

Can IEMs be as good as full sized headphones?

Reply #19
@Notat
Quote
Microphonics is translation of vibration into electricity


In the context of IEMs, the word  "microphonics" is just used  to talk of  "the noise you get when your IEM cable brushes against clothing". I don't think there's any electricity involved here.

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How much more high end do I need to go?

You have to gather informations or test what you buy.
Here's an interesting comparison of 21 popular iems, done by "dfkt" :
http://www.anythingbutipod.com/forum/showthread.php?t=15243
You can see on that comparison, that despite their relatively expensive price the Etymotics ER-6 have annoying microphonics.


Can IEMs be as good as full sized headphones?

Reply #20
If you really believe IEMs with multiple drivers perform better(wider freq range, lower distortion, etc) than IEMs with a single driver, you are quite wrong.



Do UE-11Pro(3-way) & SE530(2-way) perform better than ER4(1-way)?

What you get from multiple drivers are bass boost & more distortion.

According to D.Wilson from Etymotic Research:
Quote
Do you need a dual driver IEM, or did some marketing genius convince you that two drivers are better than one? The argument for multiple drivers holds water when there are physical limitations to filling a large room with sound, and not a 1.4cc volume in your ear canal.
What do you plan to gain from dual driver?

Can IEMs be as good as full sized headphones?

Reply #21
@udauda
These graph don't tell anything about sound quality.

The apple earbuds are crap when compared to any serious IEM, there's no doubt about that;  and I can't see how you could deduce this from first graph.

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Do UE-11Pro(3-way) & SE530(2-way) perform better than ER4(1-way)?

I guess that's hard to tell, without listening to them.

Can IEMs be as good as full sized headphones?

Reply #22
If you really believe IEMs with multiple drivers perform better(wider freq range, lower distortion, etc) than IEMs with a single driver, you are quite wrong.


This opposite statement is just as wrong. Basing a statement about the relationship of two types of tokens by looking at just two tokens is flawed logic. The existence of just one multi driver IEM that is worse than one with a single driver doesn't show anything.

[useless images]


You do know, that for the domain of IEMs the ideal, most neutral piece would have a non-flat frequency response (in contrast to speakers), right?

What you get from multiple drivers are bass boost & more distortion.


Just plain false. Compare top of the line IEMs as Westone's to your Etymotic darlings.

According to D.Wilson from Etymotic Research:
Quote
Do you need a dual driver IEM, or did some marketing genius convince you that two drivers are better than one? The argument for multiple drivers holds water when there are physical limitations to filling a large room with sound, and not a 1.4cc volume in your ear canal.
What do you plan to gain from dual driver?


So you have been tricked into drinking marketing Kool Aid B by the simple ploy of some other statement called Kool Aid A.

Can IEMs be as good as full sized headphones?

Reply #23
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You do know, that for the domain of IEMs the ideal, most neutral piece would have a non-flat frequency response (in contrast to speakers), right?

You must be referring to the case of the missing 6dB. If you take a look at Here, Here, and Here, you'd realize a diffuse-field-compensated(a human diffuse-field HRTF deducted from a linear data) flat-FR is the most suitable, even with headphones, earphones, & IEMs. (flat-FR w/ an additional bone-conducted vibration would make the bass sound more natural though)

Quote
Just plain false. Compare top of the line IEMs as Westone's to your Etymotic darlings.

Did you know, DF-compensated, Westone3(UM3) outputs audio signal only upto 10kHz? And that's a 3-way IEM. If you get a chance to fiddle around with a ITU-T P.58 compliant HATS equipped w/ IEC-60318-4 ear simulators, you'll see what I mean.

Can IEMs be as good as full sized headphones?

Reply #24
You must be referring to the case of the missing 6dB.


Nope.

...a diffuse-field-compensated(a human diffuse-field HRTF deducted from a linear data) flat-FR is the most suitable, even with headphones, earphones, & IEMs. (an additional bone-conducted vibration would be nice though)


That's the point. For stereo signals, so about 99% of all listened music, without further processing a flat headphone FR is not optimal. A headphone with a FR approximating a DF compensated FR will sound more neutral. Else you'd have to bump a sticker on the box "This IEM's flat frequency response will cause non neutral perception of audio without further processing. Please do not use without applying a proper HRTF."

Did you know, DF-compensated, Westone3(UM3) outputs audio signal only upto 10kHz? And that's a 3-way IEM. If you get a chance to fiddle around with a ITU-T P.58 compliant HATS equipped w/ IEC-60318-4 ear simulators, you'll see what I mean.


Feel free to post detailed results and a comparison to your Etymotics. I have successfully measured the thresholds of my hearing around 16kHz with a pair of UM2 using sweeps. So I somewhat doubt this claim.